Management of hair loss

Scratching of itchy scalp may contribute to hair loss.{{cite journal |last1=Bin Saif |first1=GA |last2=Ericson |first2=ME |last3=Yosipovitch |first3=G |title=The itchy scalp—scratching for an explanation. |journal=Experimental Dermatology |date=December 2011 |volume=20 |issue=12 |pages=959–68 |doi=10.1111/j.1600-0625.2011.01389.x |pmid=22092575|pmc=3233984 }}

Prevention of obesity helps. Obesity is linked to hair thinning.{{cite journal |last1=Morinaga |first1=H |last2=Mohri |first2=Y |last3=Grachtchouk |first3=M |last4=Asakawa |first4=K |last5=Matsumura |first5=H |last6=Oshima |first6=M |last7=Takayama |first7=N |last8=Kato |first8=T |last9=Nishimori |first9=Y |last10=Sorimachi |first10=Y |last11=Takubo |first11=K |last12=Suganami |first12=T |last13=Iwama |first13=A |last14=Iwakura |first14=Y |last15=Dlugosz |first15=AA |last16=Nishimura |first16=EK |title=Obesity accelerates hair thinning by stem cell-centric converging mechanisms. |journal=Nature |date=July 2021 |volume=595 |issue=7866 |pages=266–271 |doi=10.1038/s41586-021-03624-x |pmid=34163066|pmc=9600322 |bibcode=2021Natur.595..266M |s2cid=235625692 }}

{{see also|Healthy diet}}

Oils with fatty acids that has been studied to prevent dermatitis includes:{{cite journal |last1=Søyland |first1=E |last2=Funk |first2=J |last3=Rajka |first3=G |last4=Sandberg |first4=M |last5=Thune |first5=P |last6=Rustad |first6=L |last7=Helland |first7=S |last8=Middelfart |first8=K |last9=Odu |first9=S |last10=Falk |first10=ES |title=Dietary supplementation with very long-chain n-3 fatty acids in patients with atopic dermatitis. A double-blind, multicentre study. |journal=The British Journal of Dermatology |date=June 1994 |volume=130 |issue=6 |pages=757–64 |doi=10.1111/j.1365-2133.1994.tb03414.x |pmid=8011502|s2cid=25066444 }}{{cite journal |last1=Callaway |first1=J |last2=Schwab |first2=U |last3=Harvima |first3=I |last4=Halonen |first4=P |last5=Mykkänen |first5=O |last6=Hyvönen |first6=P |last7=Järvinen |first7=T |title=Efficacy of dietary hempseed oil in patients with atopic dermatitis. |journal=The Journal of Dermatological Treatment |date=April 2005 |volume=16 |issue=2 |pages=87–94 |doi=10.1080/09546630510035832 |pmid=16019622|s2cid=18445488 }}

• Corn oil: Linoleic acid (LA)
• Fish oil: Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)
• Hemp seed oil: Linoleic acid (LA), and alpha-Linolenic acid (ALA)

The scalp must be cleaned from sebum, sweat, and dirt, prior to topical application, for agents to penetrate it.

A 2020 systemic review on agents used to treat androgenic alopecia found that:{{cite journal | vauthors = Ashique S, Sandhu NK, Haque SN, Koley K | title = A Systemic Review on Topical Marketed Formulations, Natural Products, and Oral Supplements to Prevent Androgenic Alopecia: A Review | journal = Natural Products and Bioprospecting | volume = 10 | issue = 6 | pages = 345–365 | date = December 2020 | pmid = 33011954 | pmc = 7648777 | doi = 10.1007/s13659-020-00267-9 }}

• Oral supplementation of vitamin A, B, C, D, E, and trace element iron, selenium, and zinc, will prevent androgenic alopecia caused by malnutrition. Multivitamins can be used.
• Topical application of onion juice, rosemary oil, saw palmetto, pumpkin seed oil, procyanidin, garlic gel, capsaicin, caffeine, amino acids, and curcumin helped prevent hair loss.

A humidifier can be used to prevent low indoor humidity during winter (especially with indoor heating), and dry season.{{cite web |title=Seasonal Shedding Hair in Summer or Winter! |url=https://mdm-communications.com/seasonal-shedding-hair-summer-winter/2/ |website=MDM Health |date=28 October 2015 |access-date=December 9, 2021 |archive-date=December 9, 2021 |archive-url=https://web.archive.org/web/20211209232940/https://mdm-communications.com/seasonal-shedding-hair-summer-winter/2/ |url-status=live }}

Commonly, patients with seborrhoeic dermatitis experience mild redness, scaly skin lesions and in some cases hair loss.{{cite web|url=http://www.mamashealth.com/skin/seb.asp|title=What is Seborrheic Dermatitis?|access-date=June 11, 2010|url-status=live|archive-url=https://web.archive.org/web/20100420023503/http://www.mamashealth.com/skin/seb.asp|archive-date=April 20, 2010}}

Low humidity can cause adverse health effects and may cause atopic dermatitis,{{cite journal | vauthors = Engebretsen KA, Johansen JD, Kezic S, Linneberg A, Thyssen JP | title = The effect of environmental humidity and temperature on skin barrier function and dermatitis | journal = Journal of the European Academy of Dermatology and Venereology | volume = 30 | issue = 2 | pages = 223–249 | date = February 2016 | pmid = 26449379 | doi = 10.1111/jdv.13301 | s2cid = 12378072 | doi-access = free }} and seborrhoeic dermatitis.{{cite journal | vauthors = Araya M, Kulthanan K, Jiamton S | title = Clinical Characteristics and Quality of Life of Seborrheic Dermatitis Patients in a Tropical Country | journal = Indian Journal of Dermatology | volume = 60 | issue = 5 | pages = 519 | date = September 2015 | pmid = 26538714 | pmc = 4601435 | doi = 10.4103/0019-5154.164410 | doi-access = free }}

Combinations of finasteride, minoxidil and ketoconazole are more effective than individual use.{{cite journal | vauthors = Khandpur S, Suman M, Reddy BS | title = Comparative efficacy of various treatment regimens for androgenetic alopecia in men | journal = The Journal of Dermatology | volume = 29 | issue = 8 | pages = 489–498 | date = August 2002 | pmid = 12227482 | doi = 10.1111/j.1346-8138.2002.tb00314.x | s2cid = 20886812 }}

Combination therapy of LLLT or microneedling with finasteride or minoxidil demonstrated substantive increases in hair count.{{cite journal | last1=Zhou | first1=Yi | last2=Chen | first2=Chenglong | last3=Qu | first3=Qian | last4=Zhang | first4=Chunhua | last5=Wang | first5=Jin | last6=Fan | first6=Zhexiang | last7=Miao | first7=Yong | last8=Hu | first8=Zhiqi | title=The effectiveness of combination therapies for androgenetic alopecia: A systematic review and meta-analysis | journal=Dermatologic Therapy | publisher=Hindawi Limited | volume=33 | issue=4 | year=2020 | pages=e13741 | issn=1396-0296 | doi=10.1111/dth.13741 | pmid=32478968 | doi-access=free }}

Treatments for the various forms of hair loss have only moderate success.{{cite journal | vauthors = Levy LL, Emer JJ | title = Female pattern alopecia: current perspectives | journal = International Journal of Women's Health | volume = 5 | pages = 541–556 | date = August 2013 | pmid = 24039457 | pmc = 3769411 | doi = 10.2147/IJWH.S49337 | doi-access = free }} Three medications have evidence to support their use in male pattern hair loss: finasteride, dutasteride and minoxidil. They typically work better to prevent further hair loss than to regrow lost hair.

They may be used together when hair loss is progressive or further regrowth is desired after 12 months.{{cite web |url=http://www.webmd.com/skin-beauty/guide/hair-loss-treatments |title=Propecia & Rogaine for Treating Male Pattern Baldness |publisher=Webmd.com |access-date=May 19, 2010 |archive-date=July 9, 2008 |archive-url=https://web.archive.org/web/20080709023925/http://www.webmd.com/skin-beauty/guide/hair-loss-treatments |url-status=live }} Other medications include ketoconazole, and in female androgenic alopecia spironolactone and flutamide.{{cite journal | vauthors = McElwee KJ, Shapiro JS | title = Promising therapies for treating and/or preventing androgenic alopecia | journal = Skin Therapy Letter | volume = 17 | issue = 6 | pages = 1–4 | date = June 2012 | pmid = 22735503 }}

In June 2022, the FDA authorized baricitinib for the treatment of severe alopecia areata.{{cite press release | title=FDA Approves First Systemic Treatment for Alopecia Areata | website=U.S. Food and Drug Administration (FDA) | date=13 June 2022 | url=https://www.fda.gov/news-events/press-announcements/fda-approves-first-systemic-treatment-alopecia-areata | access-date=13 June 2022 | archive-date=14 June 2022 | archive-url=https://web.archive.org/web/20220614051142/https://www.fda.gov/news-events/press-announcements/fda-approves-first-systemic-treatment-alopecia-areata | url-status=live }} {{PD-notice}}{{cite press release | title=FDA Approves Lilly and Incyte's Olumiant (baricitinib) As First and Only Systemic Medicine for Adults with Severe Alopecia Areata | publisher=Eli Lilly | via=PR Newswire | date=13 June 2022 | url=https://www.prnewswire.com/news-releases/fda-approves-lilly-and-incytes-olumiant-baricitinib-as-first-and-only-systemic-medicine-for-adults-with-severe-alopecia-areata-301567120.html | access-date=13 June 2022 | archive-date=14 June 2022 | archive-url=https://web.archive.org/web/20220614034511/https://www.prnewswire.com/news-releases/fda-approves-lilly-and-incytes-olumiant-baricitinib-as-first-and-only-systemic-medicine-for-adults-with-severe-alopecia-areata-301567120.html | url-status=live }}

Minoxidil, applied topically, is widely used for the treatment of hair loss. It may be effective in helping promote hair growth in both men and women with androgenic alopecia.{{cite journal | vauthors = van Zuuren EJ, Fedorowicz Z, Schoones J | title = Interventions for female pattern hair loss | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | issue = 5 | pages = CD007628 | date = May 2016 | pmid = 27225981 | pmc = 6457957 | doi = 10.1002/14651858.CD007628.pub4 }} About 40% of men experience hair regrowth after 3–6 months.{{cite journal | vauthors = Goren A, Shapiro J, Roberts J, McCoy J, Desai N, Zarrab Z, Pietrzak A, Lotti T | display-authors = 6 | title = Clinical utility and validity of minoxidil response testing in androgenetic alopecia | journal = Dermatologic Therapy | volume = 28 | issue = 1 | pages = 13–16 | year = 2015 | pmid = 25112173 | doi = 10.1111/dth.12164 | s2cid = 205082682 | doi-access = free }} It is the only topical product that is FDA approved in America for androgenic hair loss.{{cite journal | vauthors = Varothai S, Bergfeld WF | title = Androgenetic alopecia: an evidence-based treatment update | journal = American Journal of Clinical Dermatology | volume = 15 | issue = 3 | pages = 217–230 | date = July 2014 | pmid = 24848508 | doi = 10.1007/s40257-014-0077-5 | s2cid = 31245042 }} However, increased hair loss has been reported.{{cite web|url=https://www.drugs.com/sfx/rogaine-side-effects.html|title=Rogaine Side Effects in Detail - Drugs.com|website=drugs.com|access-date=January 28, 2018|archive-date=September 22, 2017|archive-url=https://web.archive.org/web/20170922052041/https://www.drugs.com/sfx/rogaine-side-effects.html|url-status=live}}{{cite web|url = https://www.drugs.com/pro/minoxidil.html|title = Minoxidil Official FDA information, side effects and uses|publisher = Drugs.com|access-date = January 28, 2018|archive-date = September 22, 2017|archive-url = https://web.archive.org/web/20170922051930/https://www.drugs.com/pro/minoxidil.html|url-status = live}}

Ketoconazole may help in women.{{cite journal | vauthors = Piérard-Franchimont C, De Doncker P, Cauwenbergh G, Piérard GE | title = Ketoconazole shampoo: effect of long-term use in androgenic alopecia | journal = Dermatology | volume = 196 | issue = 4 | pages = 474–477 | date = 1998 | pmid = 9669136 | doi = 10.1159/000017954 | s2cid = 30635892 }}{{cite journal | vauthors = Fields JR, Vonu PM, Monir RL, Schoch JJ | title = Topical ketoconazole for the treatment of androgenetic alopecia: A systematic review | journal = Dermatologic Therapy | volume = 33 | issue = 1 | pages = e13202 | date = January 2020 | pmid = 31858672 | doi = 10.1111/dth.13202 | s2cid = 209427721 | doi-access = free }}

Finasteride is used to treat male pattern hair loss.{{Cite web|url=http://www.accessdata.fda.gov/drugsatfda_docs/label/2014/020788s024lbl.pdf|title=Propecia label|access-date=June 3, 2015|archive-date=February 10, 2017|archive-url=https://web.archive.org/web/20170210151045/http://www.accessdata.fda.gov/drugsatfda_docs/label/2014/020788s024lbl.pdf|url-status=live}} Treatment provides about 30% improvement in hair loss after six months of treatment, and effectiveness only persists as long as the drug is taken. There is no good evidence for its use in women. It may cause gynecomastia, erectile dysfunction and depression.{{cite journal | vauthors = Andersson S | title = Steroidogenic enzymes in skin | journal = European Journal of Dermatology | volume = 11 | issue = 4 | pages = 293–295 | year = 2001 | pmid = 11399532 }}

Dutasteride is also used in the treatment of male pattern hair loss and appears to have better effectiveness than finasteride for the condition.{{cite web|url=http://emc.medicines.org.uk/emc/assets/c/html/DisplayDoc.asp?DocumentID=11618|title=Avodart 0.5mg soft capsules – Summary of Product Characteristics (SmPC) – (eMC)|website=emc.medicines.org.uk|access-date=August 7, 2010|archive-date=April 26, 2006|archive-url=https://web.archive.org/web/20060426212556/http://emc.medicines.org.uk/emc/assets/c/html/displaydoc.asp?documentid=11618|url-status=dead}}{{cite journal | vauthors = Zhou Z, Song S, Gao Z, Wu J, Ma J, Cui Y | title = The efficacy and safety of dutasteride compared with finasteride in treating men with androgenetic alopecia: a systematic review and meta-analysis | journal = Clinical Interventions in Aging | volume = 14 | pages = 399–406 | date = 2019 | pmid = 30863034 | pmc = 6388756 | doi = 10.2147/CIA.S192435 | doi-access = free }}{{cite journal | vauthors = Olsen EA, Hordinsky M, Whiting D, Stough D, Hobbs S, Ellis ML, Wilson T, Rittmaster RS | display-authors = 6 | title = The importance of dual 5alpha-reductase inhibition in the treatment of male pattern hair loss: results of a randomized placebo-controlled study of dutasteride versus finasteride | journal = Journal of the American Academy of Dermatology | volume = 55 | issue = 6 | pages = 1014–1023 | date = December 2006 | pmid = 17110217 | doi = 10.1016/j.jaad.2006.05.007 }} While used off-label for male pattern hair loss in most of the world, dutasteride is specifically approved for this indication in South Korea and Japan.{{cite journal | vauthors = Choi GS, Kim JH, Oh SY, Park JM, Hong JS, Lee YS, Lee WS | title = Safety and Tolerability of the Dual 5-Alpha Reductase Inhibitor Dutasteride in the Treatment of Androgenetic Alopecia | journal = Annals of Dermatology | volume = 28 | issue = 4 | pages = 444–450 | date = August 2016 | pmid = 27489426 | pmc = 4969473 | doi = 10.5021/ad.2016.28.4.444 }}{{cite book|vauthors=Shapiro J, Otberg N|title=Hair Loss and Restoration, Second Edition|url=https://books.google.com/books?id=bJG9BwAAQBAJ&pg=PA39|date=17 April 2015|publisher=CRC Press|isbn=978-1-4822-3199-1|pages=39–|access-date=December 9, 2021|archive-date=January 12, 2023|archive-url=https://web.archive.org/web/20230112145741/https://books.google.com/books?id=bJG9BwAAQBAJ&pg=PA39|url-status=live}}

There is tentative support for spironolactone in women. Due to its feminising side effects and risk of infertility it is not often used by men.{{cite journal | vauthors = Buchanan JF, Davis LJ | title = Drug-induced infertility | journal = Drug Intelligence & Clinical Pharmacy | volume = 18 | issue = 2 | pages = 122–132 | date = February 1984 | pmid = 6141923 | doi = 10.1177/106002808401800205 | s2cid = 24807929 }}{{cite journal | vauthors = Sinclair R, Patel M, Dawson TL, Yazdabadi A, Yip L, Perez A, Rufaut NW | title = Hair loss in women: medical and cosmetic approaches to increase scalp hair fullness | journal = The British Journal of Dermatology | volume = 165 | issue = Suppl 3 | pages = 12–18 | date = December 2011 | pmid = 22171680 | doi = 10.1111/j.1365-2133.2011.10630.x | s2cid = 39734527 | doi-access = free }} It can also cause low blood pressure, high blood potassium, and abnormal heart rhythms. Also, women who are pregnant or trying to become pregnant generally cannot use the medication as it is a teratogen, and can cause ambiguous genitalia in newborn children.{{cite journal | vauthors = Rathnayake D, Sinclair R | title = Use of spironolactone in dermatology | journal = Skinmed | volume = 8 | issue = 6 | pages = 328–32; quiz 333 | year = 2010 | pmid = 21413648 }}

There is tentative evidence for flutamide in women; however, it is associated with relatively high rates of liver problems and strong recommendations have been made against its use.{{cite journal | vauthors = Giorgetti R, di Muzio M, Giorgetti A, Girolami D, Borgia L, Tagliabracci A | title = Flutamide-induced hepatotoxicity: ethical and scientific issues | journal = European Review for Medical and Pharmacological Sciences | volume = 21 | issue = 1 Suppl | pages = 69–77 | date = March 2017 | pmid = 28379593 | doi = }} Like spironolactone, flutamide is typically only used by women.{{cite journal | vauthors = Yazdabadi A, Sinclair R | title = Treatment of female pattern hair loss with the androgen receptor antagonist flutamide | journal = The Australasian Journal of Dermatology | volume = 52 | issue = 2 | pages = 132–134 | date = May 2011 | pmid = 21605098 | doi = 10.1111/j.1440-0960.2010.00735.x | s2cid = 30128397 }} Bicalutamide is another option for the treatment of female pattern hair loss.{{cite journal | vauthors = Carvalho RM, Santos LD, Ramos PM, Machado CJ, Acioly P, Frattini SC, Barcaui CB, Donda AL, Melo DF | display-authors = 6 | title = Bicalutamide and the new perspectives for female pattern hair loss treatment: What dermatologists should know | journal = Journal of Cosmetic Dermatology | volume = 21| issue = 10| date = January 2022 | pages = 4171–4175 | pmid = 35032336 | doi = 10.1111/jocd.14773 | s2cid = 253239337 }}{{cite journal | vauthors = Meyer-Gonzalez T, Bacqueville D, Grimalt R, Mengeaud V, Piraccini BM, Rudnicka L, Saceda-Corralo D, Vogt A, Vano-Galvan S | display-authors = 6 | title = Current controversies in trichology: a European expert consensus statement | journal = Journal of the European Academy of Dermatology and Venereology | volume = 35 | issue = Suppl 2 | pages = 3–11 | date = November 2021 | pmid = 34668238 | doi = 10.1111/jdv.17601 | hdl = 11585/863826 | s2cid = 239029062 | hdl-access = free }}{{cite journal | vauthors = Nestor MS, Ablon G, Gade A, Han H, Fischer DL | title = Treatment options for androgenetic alopecia: Efficacy, side effects, compliance, financial considerations, and ethics | journal = Journal of Cosmetic Dermatology | volume = 20 | issue = 12 | pages = 3759–3781 | date = December 2021 | pmid = 34741573 | doi = 10.1111/jocd.14537 | pmc = 9298335 | s2cid = 243801494 }} It has a far lower risk of liver toxicity than flutamide and is said to have an excellent safety profile.{{cite journal | vauthors = Cignarella A, Mioni R, Sabbadin C, Dassie F, Parolin M, Vettor R, Barbot M, Scaroni C | display-authors = 6 | title = Pharmacological Approaches to Controlling Cardiometabolic Risk in Women with PCOS | journal = International Journal of Molecular Sciences | volume = 21 | issue = 24 | page = 9554 | date = December 2020 | pmid = 33334002 | pmc = 7765466 | doi = 10.3390/ijms21249554 | doi-access = free }} However, bicalutamide retains a small risk of liver toxicity and for this reason periodic liver monitoring is recommended during treatment.

Low-level laser therapy or photobiomodulation is also referred to as red light therapy and cold laser therapy. It is a non-invasive treatment option.

LLLT is shown to increase hair density and growth in both genders. The types of devices (hat, comb, helmet) and duration did not alter the effectiveness,{{cite journal | last1=Liu | first1=Kao-Hui | last2=Liu | first2=Donald | last3=Chen | first3=Yu-Tsung | last4=Chin | first4=Szu-Ying | title=Comparative effectiveness of low-level laser therapy for adult androgenic alopecia: a system review and meta-analysis of randomized controlled trials | journal=Lasers in Medical Science | publisher=Springer Science and Business Media LLC | volume=34 | issue=6 | date=2019-01-31 | issn=0268-8921 | doi=10.1007/s10103-019-02723-6 | pages=1063–1069| pmid=30706177 | s2cid=59524423 }} with more emphasis to be placed on lasers compared to LEDs.{{cite journal | last1=Gupta | first1=A. K. | last2=Carviel | first2=J. L. | title=Meta-analysis of photobiomodulation for the treatment of androgenetic alopecia | journal=Journal of Dermatological Treatment | publisher=Informa UK Limited | volume=32 | issue=6 | date=2019-11-20 | issn=0954-6634 | doi=10.1080/09546634.2019.1688755 | pages=643–647| pmid=31746251 | s2cid=208185306 }} Ultraviolet and infrared light are more effective for alopecia areata, while red light and infrared light is more effective for androgenetic alopecia.{{cite journal | last1=Zhang | first1=Yuehou | last2=Su | first2=Jianlong | last3=Ma | first3=Kui | last4=Fu | first4=Xiaobing | last5=Zhang | first5=Cuiping | title=Photobiomodulation Therapy With Different Wavebands for Hair Loss: A Systematic Review and Meta-Analysis | journal=Dermatologic Surgery | publisher=Ovid Technologies (Wolters Kluwer Health) | volume=48 | issue=7 | date=2022-04-25 | issn=1076-0512 | doi=10.1097/dss.0000000000003472 | pages=737–740| pmid=35510860 | s2cid=248526019 }}

Medical reviews suggest that LLLT is as effective or potentially more than other non invasive and traditional therapies like minoxidil and finasteride but further studies such as RCTs, long term follow up studies, and larger double blinded trials need to be conducted to confirm the initial findings.{{cite journal | last1=Gupta | first1=Aditya K. | last2=Bamimore | first2=Mary A. | last3=Foley | first3=Kelly A. | title=Efficacy of non-surgical treatments for androgenetic alopecia in men and women: a systematic review with network meta-analyses, and an assessment of evidence quality | journal=Journal of Dermatological Treatment | publisher=Informa UK Limited | volume=33 | issue=1 | date=2020-04-13 | issn=0954-6634 | doi=10.1080/09546634.2020.1749547 | pages=62–72 | pmid=32250713 | s2cid=215405183 | url=https://figshare.com/articles/journal_contribution/12087042 | access-date=August 31, 2023 | archive-date=February 24, 2024 | archive-url=https://web.archive.org/web/20240224185232/https://figshare.com/articles/journal_contribution/Efficacy_of_non-surgical_treatments_for_androgenetic_alopecia_in_men_and_women_a_systematic_review_with_network_meta-analyses_and_an_assessment_of_evidence_quality/12087042 | url-status=live }}{{cite journal | last1=Darwin | first1=Evan | last2=Heyes | first2=Alexandra | last3=Hirt | first3=Penelope A. | last4=Wikramanayake | first4=Tongyu Cao | last5=Jimenez | first5=Joaquin J. | title=Low-level laser therapy for the treatment of androgenic alopecia: a review | journal=Lasers in Medical Science | publisher=Springer Science and Business Media LLC | volume=33 | issue=2 | date=2017-12-21 | issn=0268-8921 | doi=10.1007/s10103-017-2385-5 | pages=425–434| pmid=29270707 | s2cid=23783876 }}{{cite journal | last1=S | first1=Lueangarun | last2=P | first2=Visutjindaporn | last3=Y | first3=Parcharoen | last4=P | first4=Jamparuang | last5=T | first5=Tempark |title=A Systematic Review and Meta-analysis of Randomized Controlled Trials of United States Food and Drug Administration-Approved, Home-use, Low-Level Light/Laser Therapy Devices for Pattern Hair Loss: Device Design and Technology | journal=The Journal of Clinical and Aesthetic Dermatology | date=2021 | volume=14 | issue=11 | pages=E64–E75 | issn=1941-2789 | pmid=34980962 | pmc=8675345 }}

Using ones own cells and tissues and without harsh side effects, PRP is beneficial for alopecia areata{{cite journal | last1=Tejapira | first1=Kasama | last2=Yongpisarn | first2=Tanat | last3=Sakpuwadol | first3=Nawara | last4=Suchonwanit | first4=Poonkiat | title=Platelet-rich plasma in alopecia areata and primary cicatricial alopecias: A systematic review | journal=Frontiers in Medicine | publisher=Frontiers Media SA | volume=9 | date=2022-11-24 | issn=2296-858X | doi=10.3389/fmed.2022.1058431 | page=| pmid=36507528 | pmc=9731377 | doi-access=free }} and androgenetic alopecia and can be used as an alternative to minoxidil or finasteride.{{cite journal | last1=Gentile | first1=Pietro | last2=Garcovich | first2=Simone | title=Systematic Review of Platelet-Rich Plasma Use in Androgenetic Alopecia Compared with Minoxidil®, Finasteride®, and Adult Stem Cell-Based Therapy | journal=International Journal of Molecular Sciences | publisher=MDPI AG | volume=21 | issue=8 | date=2020-04-13 | issn=1422-0067 | doi=10.3390/ijms21082702 | page=2702| pmid=32295047 | pmc=7216252 | doi-access=free }} It has been documented to improve hair density and thickness in both genders.{{cite journal | last1=Evans | first1=Adam G. | last2=Mwangi | first2=James M. | last3=Pope | first3=Rand W. | last4=Ivanic | first4=Mirjana G. | last5=Botros | first5=Mina A. | last6=Glassman | first6=Gabriella E. | last7=Pearce | first7=F. Bennett | last8=Kassis | first8=Salam | title=Platelet-rich plasma as a therapy for androgenic alopecia: a systematic review and meta-analysis | journal=Journal of Dermatological Treatment | publisher=Informa UK Limited | volume=33 | issue=1 | date=2020-05-26 | issn=0954-6634 | doi=10.1080/09546634.2020.1770171 | pages=498–511 | pmid=32410524 | s2cid=218648227 | url=https://figshare.com/articles/journal_contribution/12376727 | access-date=August 31, 2023 | archive-date=February 24, 2024 | archive-url=https://web.archive.org/web/20240224185101/https://figshare.com/articles/journal_contribution/Platelet-rich_plasma_as_a_therapy_for_androgenic_alopecia_a_systematic_review_and_meta-analysis/12376727 | url-status=live }} A minimum of 3 treatments, once a month for 3 months are recommended, and afterwards a 3-6 month period of continual appointments for maintenance.{{cite journal | last1=Gupta | first1=Aditya K. | last2=Cole | first2=John | last3=Deutsch | first3=David P. | last4=Everts | first4=Peter A. | last5=Niedbalski | first5=Robert P. | last6=Panchaprateep | first6=Ratchathorn | last7=Rinaldi | first7=Fabio | last8=Rose | first8=Paul T. | last9=Sinclair | first9=Rodney | last10=Vogel | first10=James E. | last11=Welter | first11=Ryan J. | last12=Zufelt | first12=Michael D. | last13=Puig | first13=Carlos J. | title=Platelet-Rich Plasma as a Treatment for Androgenetic Alopecia | journal=Dermatologic Surgery | publisher=Ovid Technologies (Wolters Kluwer Health) | volume=45 | issue=10 | year=2019 | issn=1076-0512 | doi=10.1097/dss.0000000000001894 | pages=1262–1273| pmid=30882509 | s2cid=81980415 }} Factors that determine efficacy include amount of sessions, double versus single centrifugation, age and gender, and where the PRP is inserted.{{cite journal | last1=Gupta | first1=Aditya | last2=Bamimore | first2=Mary | title=Platelet-Rich Plasma Monotherapies for Androgenetic Alopecia: A Network Meta-Analysis and Meta-Regression Study | journal=Journal of Drugs in Dermatology | publisher=SanovaWorks | volume=21 | issue=9 | date=2022-08-01 | issn=1545-9616 | doi=10.36849/jdd.6948 | pages=943–952| pmid=36074501 | s2cid=252120370 }}

Future larger randomized controlled trials and other high quality studies are still recommended to be carried out and published for a stronger consensus.{{cite journal | last1=Oth | first1=O | last2=Stene | first2=JJ | last3=Glineur | first3=R | last4=Vujovic | first4=A | title=Injection of PRP (Platelet-rich plasma) as a treatment for androgenetic alopecia : a systematic review of the literature | journal=Revue Médicale de Bruxelles | publisher=AMUB/Revue Médicale de Bruxelles | volume=39 | issue=5 | year=2018 | issn=0035-3639 | doi=10.30637/2018.17-056 | pages=438–446| pmid=29869472 | doi-access=free }} Further development of a standardized practice for procedure is also recommended.

{{main|Hair transplantation}}

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Hair transplantation is a surgical technique that moves individual hair follicles from a part of the body called the donor site to bald or balding part of the body known as the recipient site. It is primarily used to treat male pattern baldness. In this condition, grafts containing hair follicles that are genetically resistant to balding are transplanted to bald scalp. It is also used to restore eyelashes, eyebrows, beard hair, chest hair, and pubic hair and to fill in scars caused by accidents or surgery such as face-lifts and previous hair transplants. Hair transplantation differs from skin grafting in that grafts contain almost all of the epidermis and dermis surrounding the hair follicle, and many tiny grafts are transplanted rather than a single strip of skin.

Since hair naturally grows in follicles in groups of 1 to 4 hairs, transplantation takes advantage of these naturally occurring follicular units. This achieves a more natural appearance by matching hair for hair through Follicular unit transplantation (FUT).

Donor hair can be harvested in two different ways. Small grafts of naturally-occurring units of one to four hairs, called follicular units, can be moved to balding areas of the hair restoration. These follicular units are surgically implanted in the scalp in very close proximity to one another and in large numbers. The grafts are obtained in one or both of the two primary methods of surgical extraction, follicular unit transplantation, colloquially referred to as "strip harvesting", or Follicular Unit Extraction (FUE), in which follicles are transplanted individually.

In FUT, a strip of skin containing many follicular units is extracted from the patient and dissected under a stereoscopic microscope. The site of the strip removal is stitched closed. Once divided into follicular unit grafts, each unit is individually inserted into small recipient sites made by an incision in the bald scalp. In the newer technique, roots are extracted from the donor area and divided into strips for transplantation. The strip, two to three millimeters thick, is isolated and transplanted to the bald scalp.{{cite journal | vauthors = Rashid RM, Morgan Bicknell LT | title = Follicular unit extraction hair transplant automation: options in overcoming challenges of the latest technology in hair restoration with the goal of avoiding the line scar | journal = Dermatology Online Journal | volume = 18 | issue = 9 | pages = 12 | date = September 2012 | pmid = 23031379 | doi = 10.5070/D30X57S71R }} After surgery, a bandage is worn for two days to protect the stitched strip during healing. A small strip scar remains after healing, which can be covered by scalp hair growing over the scar.

{{main|Scalp reduction}}

Scalp reduction is a surgical procedure in which the hairless region of the scalp of a bald man is reduced. This procedure can reduce the area of the scalp without hair.{{cite journal | vauthors = Bell ML | title = Role of scalp reduction in the treatment of male pattern baldness | journal = Plastic and Reconstructive Surgery | volume = 69 | issue = 2 | pages = 272–277 | date = February 1982 | pmid = 7054796 | doi = 10.1097/00006534-198202000-00016 | s2cid = 20731930 }}{{cite book |last1=Unger |first1=Martin G. |last2=Toscani |first2=Marco |year=2016 |chapter=Scalp reduction |editor1-last=Scuderi |editor1-first=Nicolò |editor2-last=Toth |editor2-first=Bryant A. |title=International Textbook of Aesthetic Surgery |chapter-url=https://www.springer.com/gp/book/9783662465981 |publisher=Springer |pages=555–556 |doi=10.1007/978-3-662-46599-8 |isbn=978-3-662-46598-1 |access-date=7 December 2016 |archive-date=August 3, 2017 |archive-url=https://web.archive.org/web/20170803211713/http://www.springer.com/gp/book/9783662465981 |url-status=live }}

Bimatoprost 0.03% has been used to grow eyebrows.{{cite journal |last1=Riahi |first1=RR |last2=Cohen |first2=PR |title=Topical Treatment of Eyebrow Hypotrichosis with Bimatoprost 0.03% Solution: Case Report and Literature Review. |journal=Cureus |date=21 May 2018 |volume=10 |issue=5 |pages=e2666 |doi=10.7759/cureus.2666 |doi-access=free |pmid=30042917 |pmc=6054329}}

The FP receptor agonist, bimatoprost, in the form of an 0.03% ophthalmic solution termed Latisse, is approved by the US Food and Drug Administration to treat hypotrichosis of the eyelashes, in particular to darken and lengthen eyelashes for cosmetic purposes.{{cite journal |last1=Choi |first1=YM |last2=Diehl |first2=J |last3=Levins |first3=PC |title=Promising alternative clinical uses of prostaglandin F2α analogs: beyond the eyelashes. |journal=Journal of the American Academy of Dermatology |date=April 2015 |volume=72 |issue=4 |pages=712–6 |doi=10.1016/j.jaad.2014.10.012 |pmid=25601618}} Also, bimatoprost may be used to treat small or underdeveloped eyelashes.{{cite web | title=Bimatoprost solution/ drops | website=DailyMed | date=18 September 2019 | url=https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=27bef7e1-750a-4ac1-ab5f-e4c0121ffcbc | access-date=4 January 2020 | archive-date=September 21, 2020 | archive-url=https://web.archive.org/web/20200921171858/https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=27bef7e1-750a-4ac1-ab5f-e4c0121ffcbc | url-status=live }}{{cite web | title=Lumigan- bimatoprost solution/ drops | website=DailyMed | date=31 July 2017 | url=https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=a5e67c75-db88-4372-bb07-c8dd15c97631 | access-date=4 January 2020 | archive-date=September 21, 2020 | archive-url=https://web.archive.org/web/20200921171612/https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=a5e67c75-db88-4372-bb07-c8dd15c97631 | url-status=live }}

Some popular plant juices sold as hair serum may, instead of growing human hair, actually inhibit the growth, including 6-gingerol found in ginger.{{cite journal | vauthors = Miao Y, Sun Y, Wang W, Du B, Xiao SE, Hu Y, Hu Z | title = 6-Gingerol inhibits hair shaft growth in cultured human hair follicles and modulates hair growth in mice | journal = PLOS ONE | volume = 8 | issue = 2 | pages = e57226 | date = 2013 | pmid = 23437345 | pmc = 3578824 | doi = 10.1371/journal.pone.0057226 | doi-access = free | bibcode = 2013PLoSO...857226M }}

Among the indigenous peoples of California, plants in the genus Marah were used as a topical treatment for hair loss, with the seeds roasted, mashed, and applied to the scalp as a salve. The cucurbitacins found in Marah are structurally similar to finasteride.{{Cite journal |last=Martin |first=Steve L |date=2009-03-01 |title=The Use of Marah Macrocarpus by the Prehistoric Indians of Coastal Southern California |url=https://journals.sagepub.com/doi/abs/10.2993/0278-0771-29.1.77 |journal=Journal of Ethnobiology |language=EN |volume=29 |issue=1 |pages=77–93 |doi=10.2993/0278-0771-29.1.77 |issn=0278-0771}}

File:CSIRO ScienceImage 2782 Brown Onions.jpg

A small 2002 study demonstrated that treatment twice daily for six weeks with crude onion juice from Australian brown onion, re-growth hair on alopecia areata (spot baldness) in 86.9% of the 23 participants.{{cite journal | vauthors = Sharquie KE, Al-Obaidi HK | title = Onion juice (Allium cepa L.), a new topical treatment for alopecia areata | journal = The Journal of Dermatology | volume = 29 | issue = 6 | pages = 343–346 | date = June 2002 | pmid = 12126069 | doi = 10.1111/j.1346-8138.2002.tb00277.x | s2cid = 24116769 }} Twice as many flavonols are found in red onion than in yellow onion.{{cite journal | vauthors = Slimestad R, Fossen T, Vågen IM | title = Onions: a source of unique dietary flavonoids | journal = Journal of Agricultural and Food Chemistry | volume = 55 | issue = 25 | pages = 10067–10080 | date = December 2007 | pmid = 17997520 | doi = 10.1021/jf0712503 | bibcode = 2007JAFC...5510067S }} Also, non-organic onions might contain pesticides on the peel and in the first scaly leaf. Compounds found in onion that stimulate hair growth:

• Quercetin:
• Quercetin (a flavonoid found in vegan food) supplements, has been suggested to treat baldness. A 2012 study demonstrated that alopecia areata could be used to prevent ant treated with quercetin in mice.{{cite journal | vauthors = Wikramanayake TC, Villasante AC, Mauro LM, Perez CI, Schachner LA, Jimenez JJ | title = Prevention and treatment of alopecia areata with quercetin in the C3H/HeJ mouse model | journal = Cell Stress & Chaperones | volume = 17 | issue = 2 | pages = 267–274 | date = March 2012 | pmid = 22042611 | pmc = 3273564 | doi = 10.1007/s12192-011-0305-3 }} Quercetin is found in onions primarily in the peel and the first scaly leaf but not in the flesh.{{cite journal | vauthors = Kwak JH, Seo JM, Kim NH, Arasu MV, Kim S, Yoon MK, Kim SJ | title = Variation of quercetin glycoside derivatives in three onion (Allium cepa L.) varieties | journal = Saudi Journal of Biological Sciences | volume = 24 | issue = 6 | pages = 1387–1391 | date = September 2017 | pmid = 28855836 | pmc = 5562462 | doi = 10.1016/j.sjbs.2016.05.014 }} Onion bulb size or weight does not appear to be affected by quercetin concentration.
• A 2020 study demonstrated that quercitrin stimulated hair shaft growth in cultured human hair follicles.{{cite journal | vauthors = Kim J, Kim SR, Choi YH, Shin JY, Kim CD, Kang NG, Park BC, Lee S | display-authors = 6 | title = Quercitrin Stimulates Hair Growth with Enhanced Expression of Growth Factors via Activation of MAPK/CREB Signaling Pathway | journal = Molecules | volume = 25 | issue = 17 | page = 4004 | date = September 2020 | pmid = 32887384 | pmc = 7504764 | doi = 10.3390/molecules25174004 | doi-access = free }}
• Volatile compounds responsible for pungency and tearing in onions when they are cut (e.g. syn-propanethial S-oxide gas). However, no formal studies have been conducted to evaluate if these compounds promote hair growth or if they help other compounds to penetrate the skin to form hair follicles.
• To use the volatile compounds: Onions must be extracted and applied topically quickly before the volatile compounds evaporate. The extract will cause tearing eyes, but it can be prevented with a shower cap, or a pair of swimming goggles.
• To discard the volatile compounds: The onion juice is extracted and stored for a short while to evaporate the volatile compounds. The extract will not cause tearing eyes. Also, both genetically modified, and plant breed onions have been produced with significantly reduced levels of tear-inducing lachrymatory factor.{{cite journal | vauthors = Eady CC, Kamoi T, Kato M, Porter NG, Davis S, Shaw M, Kamoi A, Imai S | display-authors = 6 | title = Silencing onion lachrymatory factor synthase causes a significant change in the sulfur secondary metabolite profile | journal = Plant Physiology | volume = 147 | issue = 4 | pages = 2096–2106 | date = August 2008 | pmid = 18583530 | pmc = 2492635 | doi = 10.1104/pp.108.123273 }}{{cite news |title=Cutting this new type of onion won't make you cry |url=https://www.independent.co.uk/life-style/onion-no-crying-cut-up-tears-sting-juice-a8149821.html |work=The Independent |date=9 January 2018 |language=en |access-date=September 7, 2021 |archive-date=September 7, 2021 |archive-url=https://web.archive.org/web/20210907223821/https://www.independent.co.uk/life-style/onion-no-crying-cut-up-tears-sting-juice-a8149821.html |url-status=live }}

A 2025 study suggests that caffeine may help with hair growth by stimulating hair follicles and counteracting the effects of DHT, a hormone linked to hair loss. Caffeine is believed to increase blood circulation in the scalp and extend the hair's growth phase, which could potentially help slow down the hair thinning process. While caffeine-based hair products are popular, more research is needed to fully confirm their effectiveness.{{cite journal |last1=Szendzielorz |first1=Ewelina |last2=Spiewak |first2=Radoslaw |title=Caffeine as an Active Molecule in Cosmetic Products for Hair Loss: Its Mechanisms of Action in the Context of Hair Physiology and Pathology |journal=Molecules |date=4 January 2025 |volume=30 |issue=1 |pages=167 |doi=10.3390/molecules30010167|doi-access=free |pmid=39795223 |pmc=11720832 }}

Dietary supplements are not typically recommended.{{cite journal | vauthors = Rogers NE, Avram MR | title = Medical treatments for male and female pattern hair loss | journal = Journal of the American Academy of Dermatology | volume = 59 | issue = 4 | pages = 547–66; quiz 567–8 | date = October 2008 | pmid = 18793935 | doi = 10.1016/j.jaad.2008.07.001 }} Many people use unproven treatments,{{cite journal | vauthors = Banka N, Bunagan MJ, Shapiro J | title = Pattern hair loss in men: diagnosis and medical treatment | journal = Dermatologic Clinics | volume = 31 | issue = 1 | pages = 129–140 | date = January 2013 | pmid = 23159182 | doi = 10.1016/j.det.2012.08.003 }} but there is little evidence of the effectiveness of vitamins, minerals, or other dietary supplements regrowing hair or retaining hair. There is no evidence for biotin (vitamin B7). While lacking both evidence and expert recommendation, there is a large market for hair growth supplements, especially for products that contain biotin.

However, one small trial of saw palmetto which shows tentative benefit in those with mild to moderate androgenetic alopecia. There was no good evidence for gingko, aloe vera, ginseng, bergamot, or hibiscus as of 2011.{{cite journal | vauthors = Blumeyer A, Tosti A, Messenger A, Reygagne P, Del Marmol V, Spuls PI, Trakatelli M, Finner A, Kiesewetter F, Trüeb R, Rzany B, Blume-Peytavi U | display-authors = 6 | title = Evidence-based (S3) guideline for the treatment of androgenetic alopecia in women and in men | journal = Journal der Deutschen Dermatologischen Gesellschaft | volume = 9 | issue = Suppl 6 | pages = S1-57 | date = October 2011 | pmid = 21980982 | doi = 10.1111/j.1610-0379.2011.07802.x | s2cid = 29821046 }}

Radiation induces hair loss through damage to hair follicle stem cell progenitors and alteration of keratin expression.{{cite journal | vauthors = Nanashima N, Ito K, Ishikawa T, Nakano M, Nakamura T | title = Damage of hair follicle stem cells and alteration of keratin expression in external radiation-induced acute alopecia | journal = International Journal of Molecular Medicine | volume = 30 | issue = 3 | pages = 579–584 | date = September 2012 | pmid = 22692500 | doi = 10.3892/ijmm.2012.1018 | doi-access = free }}{{cite journal | vauthors = Kamiya K, Sasatani M | title = [Effects of radiation exposure on human body] | journal = Nihon Rinsho. Japanese Journal of Clinical Medicine | volume = 70 | issue = 3 | pages = 367–374 | date = March 2012 | pmid = 22514910 }} Radiation therapy has been associated with increased mucin production in hair follicles.{{cite journal | vauthors = Takeda H, Nakajima K, Kaneko T, Harada K, Matsuzaki Y, Sawamura D | title = Follicular mucinosis associated with radiation therapy | journal = The Journal of Dermatology | volume = 38 | issue = 11 | pages = 1116–1118 | date = November 2011 | pmid = 22034994 | doi = 10.1111/j.1346-8138.2010.01187.x | s2cid = 31876890 }}

Studies have suggested electromagnetic radiation as a therapeutic growth stimulant in alopecia.{{cite journal | vauthors = Kalia S, Lui H | title = Utilizing electromagnetic radiation for hair growth: a critical review of phototrichogenesis | journal = Dermatologic Clinics | volume = 31 | issue = 1 | pages = 193–200 | date = January 2013 | pmid = 23159188 | doi = 10.1016/j.det.2012.08.018 }}

File:Wigs on display.jpg in wig design.]] Certain hair shampoos and ointments visually thicken existing hair, without affecting the growth cycle.{{cite journal | vauthors = Davis MG, Thomas JH, van de Velde S, Boissy Y, Dawson TL, Iveson R, Sutton K | title = A novel cosmetic approach to treat thinning hair | journal = The British Journal of Dermatology | volume = 165 | issue = Suppl 3 | pages = 24–30 | date = December 2011 | pmid = 22171682 | doi = 10.1111/j.1365-2133.2011.10633.x | s2cid = 21918537 }} There have also been developments in the fashion industry with wig design. The fashion accessory has also been shown to be a source of psychological support for women undergoing chemotherapy, with cancer survivors in one study describing their wig as a "constant companion".{{cite journal | vauthors = Zannini L, Verderame F, Cucchiara G, Zinna B, Alba A, Ferrara M | title = 'My wig has been my journey's companion': perceived effects of an aesthetic care programme for Italian women suffering from chemotherapy-induced alopecia | journal = European Journal of Cancer Care | volume = 21 | issue = 5 | pages = 650–660 | date = September 2012 | pmid = 22339814 | doi = 10.1111/j.1365-2354.2012.01337.x | doi-access = free }} Other studies in women have demonstrated a more mixed psychosocial impact of hairpiece use.{{cite journal | vauthors = Inui S, Inoue T, Itami S | title = Psychosocial impact of wigs or hairpieces on perceived quality of life level in female patients with alopecia areata | journal = The Journal of Dermatology | volume = 40 | issue = 3 | pages = 225–226 | date = March 2013 | pmid = 23252418 | doi = 10.1111/1346-8138.12040 | s2cid = 43795003 }}

Specialized tattoos, commonly known as scalp micropigmentation, can mimic the appearance of a short buzzed haircut.{{cite news |title=Considering a hair tattoo? Pros and cons to consider before you commit |author=Elisabeth Leamy |url=https://abcnews.go.com/blogs/health/2012/05/31/considering-a-hair-tattoo-pros-and-cons-to-consider-before-you-commit/ |newspaper=ABC News |date=May 31, 2012 |access-date=December 16, 2012 |archive-date=April 11, 2019 |archive-url=https://web.archive.org/web/20190411205715/https://abcnews.go.com/blogs/health/2012/05/31/considering-a-hair-tattoo-pros-and-cons-to-consider-before-you-commit/ |url-status=live }}

{{main|Human hair growth}}

File:Skin.png with mesenchymal dermal papilla, labelled at top, location of hair follicle stem cells and thought to be site of action of DHT.]]

Type 1 and 2 5α reductase enzymes are present at pilosebaceous units in papillae of individual hair follicles. They catalyse formation of the androgens testosterone and DHT, which in turn regulate hair growth. Androgens have different effects at different follicles: they stimulate IGF-1 at facial hair, causing hair regrowth, but stimulate TGF β1, TGF β2, dickkopf1 and IL-6 at the scalp, causing hair follicle miniaturisation.{{cite journal | vauthors = Inui S, Itami S | title = Androgen actions on the human hair follicle: perspectives | journal = Experimental Dermatology | volume = 22 | issue = 3 | pages = 168–171 | date = March 2013 | pmid = 23016593 | doi = 10.1111/exd.12024 | s2cid = 33521841 | doi-access = free }}

Female androgenic alopecia is characterized by diffuse crown thinning without hairline recession, and like its male counterpart rarely leads to total hair loss. Finasteride and minoxidil are usually first line therapy for its treatment. Other options include topical or systemic spironolactone or flutamide, although they have a high incidence of feminising side effects and are better tolerated in female androgenic hair loss.

More advanced cases may be resistant or unresponsive to medical therapy, however, and require hair transplantation. Naturally-occurring units of one to four hairs, called follicular units, are excised and moved to areas of hair restoration. These follicular units are surgically implanted in the scalp in close proximity and in large numbers. The grafts are obtained from either Follicular Unit Transplantation (FUT) – colloquially referred to as "strip harvesting" – or Follicular Unit Extraction (FUE). In the former, a strip of skin with follicular units is extracted and dissected into individual follicular unit grafts. The surgeon then implants the grafts into small incisions, called recipient sites.{{cite journal | vauthors = Caroli S, Pathomvanich D, Amonpattana K, Kumar A | title = Current status of hair restoration surgery | journal = International Surgery | volume = 96 | issue = 4 | pages = 345–351 | year = 2011 | pmid = 22808618 | doi = 10.9738/cc31.1 | doi-access = free }}{{cite journal | vauthors = Rose PT | title = The latest innovations in hair transplantation | journal = Facial Plastic Surgery | volume = 27 | issue = 4 | pages = 366–377 | date = August 2011 | pmid = 21792780 | doi = 10.1055/s-0031-1283055 | s2cid = 260138453 }} Specialized scalp tattoos can also mimic the appearance of a short buzzed haircut.{{cite news |title=Considering a hair tattoo? Pros and cons to consider before you commit |author=Elisabeth Leamy |url=https://abcnews.go.com/blogs/health/2012/05/31/considering-a-hair-tattoo-pros-and-cons-to-consider-before-you-commit/ |newspaper=ABC News |date=May 31, 2012 |access-date=December 16, 2012 |author-link=Elisabeth Leamy |archive-date=April 11, 2019 |archive-url=https://web.archive.org/web/20190411205715/https://abcnews.go.com/blogs/health/2012/05/31/considering-a-hair-tattoo-pros-and-cons-to-consider-before-you-commit/ |url-status=live }} Androgenic alopecia also occurs in women, and more often presents as diffuse thinning without hairline recession. Like its male counterpart, the condition rarely leads to total hair loss. Treatment options are similar to those for men, although topical or systemic estrogen is used more often.{{cite web |url=https://www.nlm.nih.gov/medlineplus/ency/article/001173.htm |title=Female pattern baldness |access-date=December 15, 2012 |date=December 15, 2012 |publisher=MedlinePlus |archive-date=December 1, 2012 |archive-url=https://web.archive.org/web/20121201014315/http://www.nlm.nih.gov/medlineplus/ency/article/001173.htm |url-status=live }}{{cite journal | vauthors = Kovalevsky G, Ballagh SA, Stanczyk FZ, Lee J, Cooper J, Archer DF | title = Levonorgestrel effects on serum androgens, sex hormone-binding globulin levels, hair shaft diameter, and sexual function | journal = Fertility and Sterility | volume = 93 | issue = 6 | pages = 1997–2003 | date = April 2010 | pmid = 19394598 | doi = 10.1016/j.fertnstert.2008.12.095 | doi-access = free }}

Latanoprost and bimatoprost are specific PGF2a analogues applied topically, and have been found to lengthen eyelashes,{{cite journal | vauthors = Law SK | title = Bimatoprost in the treatment of eyelash hypotrichosis | journal = Clinical Ophthalmology | volume = 4 | pages = 349–358 | date = April 2010 | pmid = 20463804 | pmc = 2861943 | doi = 10.2147/opth.s6480 | doi-access = free }}{{cite journal | vauthors = Tosti A, Pazzaglia M, Voudouris S, Tosti G | title = Hypertrichosis of the eyelashes caused by bimatoprost | journal = Journal of the American Academy of Dermatology | volume = 51 | issue = 5 Suppl | pages = S149–S150 | date = November 2004 | pmid = 15577756 | doi = 10.1016/j.jaad.2004.05.002 }} darken hair pigmentation{{cite journal | vauthors = Wand M | title = Latanoprost and hyperpigmentation of eyelashes | journal = Archives of Ophthalmology | volume = 115 | issue = 9 | pages = 1206–1208 | date = September 1997 | pmid = 9298071 | doi = 10.1001/archopht.1997.01100160376025 }} and elongate hair. Bimatoprost is available as treatment for eyelash growth.{{cite journal | vauthors = Banaszek A | title = Company profits from side effects of glaucoma treatment | journal = CMAJ | volume = 183 | issue = 14 | pages = E1058 | date = October 2011 | pmid = 21876012 | pmc = 3185096 | doi = 10.1503/cmaj.109-3919 }} Latanoprost has shown ability to promote scalp hair density and pigmentation,{{cite journal | vauthors = Blume-Peytavi U, Lönnfors S, Hillmann K, Garcia Bartels N | title = A randomized double-blind placebo-controlled pilot study to assess the efficacy of a 24-week topical treatment by latanoprost 0.1% on hair growth and pigmentation in healthy volunteers with androgenetic alopecia | journal = Journal of the American Academy of Dermatology | volume = 66 | issue = 5 | pages = 794–800 | date = May 2012 | pmid = 21875758 | doi = 10.1016/j.jaad.2011.05.026 }} and is theorized to function at the dermal papilla.{{cite journal | vauthors = Johnstone MA, Albert DM | title = Prostaglandin-induced hair growth | journal = Survey of Ophthalmology | volume = 47 | issue = Suppl 1 | pages = S185–S202 | date = August 2002 | pmid = 12204716 | doi = 10.1016/s0039-6257(02)00307-7 }} A study found latanoprost ineffective on eyelashes in a patient with alopecia areata.{{cite journal | vauthors = Roseborough I, Lee H, Chwalek J, Stamper RL, Price VH | title = Lack of efficacy of topical latanoprost and bimatoprost ophthalmic solutions in promoting eyelash growth in patients with alopecia areata | journal = Journal of the American Academy of Dermatology | volume = 60 | issue = 4 | pages = 705–706 | date = April 2009 | pmid = 19293023 | doi = 10.1016/j.jaad.2008.08.029 }} It has also been found ineffective in treatment of eyebrow hair loss.{{cite journal | vauthors = Ross EK, Bolduc C, Lui H, Shapiro J | title = Lack of efficacy of topical latanoprost in the treatment of eyebrow alopecia areata | journal = Journal of the American Academy of Dermatology | volume = 53 | issue = 6 | pages = 1095–1096 | date = December 2005 | pmid = 16310083 | doi = 10.1016/j.jaad.2005.06.031 | doi-access = free }}

Estrogens are indirect anti-androgens and can be used to treat androgenetic hair loss in women with oral contraceptives. Systemic estrogen increases SHBG, which binds androgens, including testosterone and DHT, in turn reducing their bioavailability. Topical formulations are available in Europe. Hair follicles have estrogen receptors and it is theorized that topical compounds act on them directly to promote hair growth and antagonize androgen action. Large clinical studies showing effectiveness are absent. Topical treatment is also usually unavailable in North America.

There is tentative evidence for cyproterone acetate in women.

In December 2012, topical application of IGF-1 in a liposomal vehicle led to thicker and more rapid hair growth in transgenic mice with androgenic alopecia. The study did not show measurable systemic levels or hematopoietic side effects, suggesting potential for use in humans.{{cite journal | vauthors = Castro RF, Azzalis LA, Feder D, Perazzo FF, Pereira EC, Junqueira VB, Rocha KC, Machado CD, Paschoal FC, Gnann LA, Fonseca FL | display-authors = 6 | title = Safety and efficacy analysis of liposomal insulin-like growth factor-1 in a fluid gel formulation for hair-loss treatment in a hamster model | journal = Clinical and Experimental Dermatology | volume = 37 | issue = 8 | pages = 909–912 | date = December 2012 | pmid = 22924775 | doi = 10.1111/j.1365-2230.2012.04441.x | s2cid = 21021986 }} Low energy radiofrequency irradiation induces IGF-1 in cultured human dermal papilla cells.{{cite journal | vauthors = Yoon SY, Kim KT, Jo SJ, Cho AR, Jeon SI, Choi HD, Kim KH, Park GS, Pack JK, Kwon OS, Park WY | display-authors = 6 | title = Induction of hair growth by insulin-like growth factor-1 in 1,763 MHz radiofrequency-irradiated hair follicle cells | journal = PLOS ONE | volume = 6 | issue = 12 | pages = e28474 | year = 2011 | pmid = 22164296 | pmc = 3229574 | doi = 10.1371/journal.pone.0028474 | editor1-last = Najbauer | doi-access = free | bibcode = 2011PLoSO...628474Y | editor1-first = Joseph }} Adenosine stimulates dermal papillae in vitro to induce IGF-1, along with fibroblast growth factors FGF7, FGF-2 and VEGF. β-catenin transcription increased, which promotes dermal papillae as well. Dietary isoflavones increase IGF production in scalp dermal papillae in transgenic mice.{{cite journal | vauthors = Zhao J, Harada N, Kurihara H, Nakagata N, Okajima K | title = Dietary isoflavone increases insulin-like growth factor-I production, thereby promoting hair growth in mice | journal = The Journal of Nutritional Biochemistry | volume = 22 | issue = 3 | pages = 227–233 | date = March 2011 | pmid = 20576422 | doi = 10.1016/j.jnutbio.2010.01.008 }} Topical capsaicin also stimulates IGF at hair follicles via release of vanilloid receptor-1, which in turn leads to more CGRP.{{cite journal | vauthors = Okajima K, Harada N | title = Promotion of insulin-like growth factor-I production by sensory neuron stimulation; molecular mechanism(s) and therapeutic implications | journal = Current Medicinal Chemistry | volume = 15 | issue = 29 | pages = 3095–3112 | year = 2008 | pmid = 19075656 | doi = 10.2174/092986708786848604 }} Ascorbic acid has led to increased IGF expression in vitro.{{cite journal | vauthors = Kwack MH, Shin SH, Kim SR, Im SU, Han IS, Kim MK, Kim JC, Sung YK | display-authors = 6 | title = l-Ascorbic acid 2-phosphate promotes elongation of hair shafts via the secretion of insulin-like growth factor-1 from dermal papilla cells through phosphatidylinositol 3-kinase | journal = The British Journal of Dermatology | volume = 160 | issue = 6 | pages = 1157–1162 | date = June 2009 | pmid = 19416266 | doi = 10.1111/j.1365-2133.2009.09108.x | s2cid = 42210965 }}

{{Main|Hair cloning}}

Although follicles were previously thought gone in areas of complete baldness, they are more likely dormant, as recent studies have shown the scalp contains the stem cells from which the follicles arose.{{cite journal | vauthors = Garza LA, Yang CC, Zhao T, Blatt HB, Lee M, He H, Stanton DC, Carrasco L, Spiegel JH, Tobias JW, Cotsarelis G | display-authors = 6 | title = Bald scalp in men with androgenetic alopecia retains hair follicle stem cells but lacks CD200-rich and CD34-positive hair follicle progenitor cells | journal = The Journal of Clinical Investigation | volume = 121 | issue = 2 | pages = 613–622 | date = February 2011 | pmid = 21206086 | pmc = 3026732 | doi = 10.1172/JCI44478 }} Research on these follicular stem cells may lead to successes in treating baldness through hair multiplication (HM), also known as hair cloning.

Per a May 2015 review, no successful strategy to generate human hair follicles, for hair regrowth, from adult stem cells has yet been reported.{{cite journal | vauthors = Balañá ME, Charreau HE, Leirós GJ | title = Epidermal stem cells and skin tissue engineering in hair follicle regeneration | journal = World Journal of Stem Cells | volume = 7 | issue = 4 | pages = 711–727 | date = May 2015 | pmid = 26029343 | pmc = 4444612 | doi = 10.4252/wjsc.v7.i4.711 | doi-access = free }} However, in April 2016, scientists from Japan published results of their work in which they created human skin from induced pluripotent stem cells; implanted into laboratory mice, the cells generated skin with hair and glands.{{cite journal | vauthors = Takagi R, Ishimaru J, Sugawara A, Toyoshima KE, Ishida K, Ogawa M, Sakakibara K, Asakawa K, Kashiwakura A, Oshima M, Minamide R, Sato A, Yoshitake T, Takeda A, Egusa H, Tsuji T | display-authors = 6 | title = Bioengineering a 3D integumentary organ system from iPS cells using an in vivo transplantation model | journal = Science Advances | volume = 2 | issue = 4 | pages = e1500887 | date = April 2016 | pmid = 27051874 | pmc = 4820374 | doi = 10.1126/sciadv.1500887 | bibcode = 2016SciA....2E0887T }}

From 2005 to 2007, Curis and Procter & Gamble collaborated on developing a topical hedgehog agonist for hair loss; the agent did not meet safety standards, and the program was terminated.{{cite news|last1=Weintraub|first1=Arlene|title=Curis and Genentech Unleash the Hedgehog to Fight a Deadly Skin Cancer|url=http://www.xconomy.com/boston/2011/06/28/curis-and-genentech-unleash-the-hedgehog-to-fight-a-deadly-skin-cancer/?single_page=true|work=Xconomy|date=28 June 2011|access-date=November 9, 2016|archive-date=November 9, 2016|archive-url=https://web.archive.org/web/20161109221622/http://www.xconomy.com/boston/2011/06/28/curis-and-genentech-unleash-the-hedgehog-to-fight-a-deadly-skin-cancer/?single_page=true|url-status=live}}{{cite web|title=Curis Form 8-K: Termination of a Material Definitive Agreement.|url=https://www.sec.gov/Archives/edgar/data/1108205/000119312507109693/d8k.htm|publisher=SEC EDGAR|date=May 10, 2007|access-date=November 9, 2016|archive-date=November 9, 2016|archive-url=https://web.archive.org/web/20161109222303/https://www.sec.gov/Archives/edgar/data/1108205/000119312507109693/d8k.htm|url-status=live}} In 2008, researchers at the University of Bonn announced they have found the genetic basis of two distinct forms of inherited hair loss. They found the gene P2RY5 causes a rare, inherited form of hair loss called hypotrichosis simplex. It is the first receptor in humans known to play a role in hair growth.{{cite journal | vauthors = Pasternack SM, von Kügelgen I, Al Aboud K, Lee YA, Rüschendorf F, Voss K, Hillmer AM, Molderings GJ, Franz T, Ramirez A, Nürnberg P, Nöthen MM, Betz RC | display-authors = 6 | title = G protein-coupled receptor P2Y5 and its ligand LPA are involved in maintenance of human hair growth | journal = Nature Genetics | volume = 40 | issue = 3 | pages = 329–334 | date = March 2008 | pmid = 18297070 | doi = 10.1038/ng.84 | s2cid = 20241237 }}{{cite journal | vauthors = Shimomura Y, Wajid M, Ishii Y, Shapiro L, Petukhova L, Gordon D, Christiano AM | title = Disruption of P2RY5, an orphan G protein-coupled receptor, underlies autosomal recessive woolly hair | journal = Nature Genetics | volume = 40 | issue = 3 | pages = 335–339 | date = March 2008 | pmid = 18297072 | doi = 10.1038/ng.100 | s2cid = 1635950 }}{{cite journal | vauthors = Sprecher E | title = Disentangling the roots of inherited hair disorders | journal = Nature Genetics | volume = 40 | issue = 3 | pages = 265–266 | date = March 2008 | pmid = 18305473 | doi = 10.1038/ng0308-265 | s2cid = 2311629 }} Researchers found that disruption of the gene SOX21 in mice caused cyclical hair loss. Research has suggested SOX21 as a master regulator of hair shaft cuticle differentiation, with its disruption causing cyclical alopecia in mice models.{{cite journal | vauthors = Kiso M, Tanaka S, Saba R, Matsuda S, Shimizu A, Ohyama M, Okano HJ, Shiroishi T, Okano H, Saga Y | display-authors = 6 | title = The disruption of Sox21-mediated hair shaft cuticle differentiation causes cyclic alopecia in mice | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 106 | issue = 23 | pages = 9292–9297 | date = June 2009 | pmid = 19470461 | pmc = 2695080 | doi = 10.1073/pnas.0808324106 | doi-access = free | bibcode = 2009PNAS..106.9292K }} Deletion of SOX21 dramatically affects hair lipids.{{cite journal | vauthors = Kawaminami S, Breakspear S, Saga Y, Noecker B, Masukawa Y, Tsuchiya M, Oguri M, Inoue Y, Ishikawa K, Okamoto M | display-authors = 6 | title = Deletion of the Sox21 gene drastically affects hair lipids | journal = Experimental Dermatology | volume = 21 | issue = 12 | pages = 974–976 | date = December 2012 | pmid = 23171466 | doi = 10.1111/exd.12050 | s2cid = 205126099 | doi-access = free }}

{{Reflist|30em}}

• [http://www.aafp.org/afp/990415ap/2189.html "Medical Treatments for Balding in Men"], April 1999, American Family Physician (medical journal)

{{Human hair}}

{{Other dermatological preparations}}

Category:Dermatologic procedures

Category:Plastic surgical procedures