antidote

{{Short description|Substance that can counteract a form of poisoning}}

{{Other uses}}

{{Distinguish|anecdote}}

An antidote is a substance that can counteract a form of poisoning.{{DorlandsDict|one/000006009|antidote}}. The term ultimately derives from the Greek term φάρμακον ἀντίδοτον (pharmakon antidoton), "(medicine) given as a remedy". An older term in English which is now rare is atterlothe, derived from "atter" ("poison" or "venom").{{cite web |title=atterlothe |url=https://www.oed.com/dictionary/atterlothe_n?tab=meaning_and_use |website=OED |access-date=27 December 2024}} Antidotes for anticoagulants are sometimes referred to as reversal agents.{{cite journal| pmc=4899056 | pmid=27330657 | doi=10.5811/westjem.2016.3.29294 | volume=17 | issue=3 | title=Anticoagulation Reversal and Treatment Strategies in Major Bleeding: Update 2016 | year=2016 | author=Christos S, Naples R | journal=West J Emerg Med | pages=264–70}}

The antidotes for some particular toxins are manufactured by injecting the toxin into an animal in small doses and extracting the resulting antibodies from the host animals' blood. This results in an antivenom that can be used to counteract venom produced by certain species of snakes, spiders, and other venomous animals. Some animal venoms, especially those produced by arthropods (such as certain spiders, scorpions, and bees) are only potentially lethal when they provoke allergic reactions and induce anaphylactic shock; as such, there is no "antidote" for these venoms; however anaphylactic shock can be treated (e.g. with epinephrine).

Some other toxins have no known antidote. For example, the poison batrachotoxin – a highly poisonous steroidal alkaloid derived from various poison dart frogs, certain beetles, and birds – has no antidote, and as a result, is often fatal if it enters the human body in sufficient quantities.

Mechanical approaches

Ingested poisons are frequently treated by the oral administration of activated charcoal, which adsorbs the poison and flushes it from the digestive tract, thereby removing a large part of the toxin.

Poisons which are injected into the body (such as those from bites or stings from venomous animals) are usually treated by the use of a constriction band which limits the flow of lymph and/or blood to the area, thus slowing the circulation of the poison around the body.{{Cite journal|last=Smith|first=T. A.|last2=Figge|first2=H. L.|date=October 1991|title=Treatment of snakebite poisoning|url=https://pubmed.ncbi.nlm.nih.gov/1781479|journal=American Journal of Hospital Pharmacy|volume=48|issue=10|pages=2190–2196|issn=0002-9289|pmid=1781479}} This should not be confused with the use of a tourniquet which cuts off blood flow completely – often leading to the loss of the limb.

Techniques to identify antidotes

In early 2019, a group of researchers in Australia published the finding of a new box jellyfish venom antidote using CRISPR.{{Cite web|url=https://the-crispr.com/antidote-to-deadly-jellyfish-identified-using-crispr/|title=Antidote to deadly jellyfish identified using CRISPR|last=The-Crispr|date=2019-05-13|website=The Crispr|language=en-US|access-date=2019-08-08}} The technology had been used to functionally inactivate genes in human cell lines and identify the peripheral membrane protein ATP2B1, a calcium transporting ATPase, as one host factor required for box jellyfish venom cytotoxicity.{{Cite journal|last1=Neely|first1=G. Gregory|last2=Seymour|first2=Jamie E.|last3=Hesselson|first3=Daniel|last4=Nguyen|first4=David T.|last5=Qiao-Ping Wang|last6=Khuong|first6=Thang M.|last7=Oyston|first7=Lisa|last8=Littleboy|first8=Jamie B.|last9=Manion|first9=John|date=2019-04-30|title=Molecular dissection of box jellyfish venom cytotoxicity highlights an effective venom antidote|journal=Nature Communications|language=en|volume=10|issue=1|pages=1655|doi=10.1038/s41467-019-09681-1|pmid=31040274|pmc=6491561|bibcode=2019NatCo..10.1655L|issn=2041-1723}}

List of antidotes

class="sortable wikitable"
width=350pt| Agent

! Indication

Activated charcoal with sorbitol

| Used for many oral toxins

Theophylline or Caffeine

| Adenosine receptor agonist poisoning

Antimuscarinic drugs (e.g. Atropine)

| Organophosphate and carbamate insecticides, nerve agents, some poison mushrooms

Beta blocker

| Theophylline

Calcium chloride{{cite web | title=Calcium channel blocker poisoning | website=UpToDate | url=https://www.uptodate.com/contents/calcium-channel-blocker-poisoning | access-date=2019-07-09}}

| Calcium channel blocker toxicity, black widow spider bites

Calcium gluconate

| Calcium channel blocker toxicity, hydrofluoric acid burns

Chelators such as EDTA, dimercaprol (BAL), penicillamine, and 2,3-dimercaptosuccinic acid (DMSA, succimer)

| Heavy metal poisoning

Cyanide antidotes (hydroxocobalamin, amyl nitrite, sodium nitrite, or thiosulfate)

| Cyanide poisoning

Cyproheptadine

| Serotonin syndrome

Deferoxamine mesylate

| Iron poisoning

Digoxin Immune Fab antibody (Digibind and Digifab)

| Digoxin poisoning, Oleander ingestion {{Cite web|url=https://calpoison.org/news/cardiac-glycoside-poisoning|title=Naturally Occurring Cardiac Glycoside Poisoning · California Poison Control System (CPCS)}}

Diphenhydramine hydrochloride and benztropine mesylate

| Extrapyramidal reactions associated with antipsychotics

100% Ethanol or fomepizole

| Ethylene glycol poisoning and methanol poisoning

Flumazenil

| Benzodiazepine overdose

100% oxygen or hyperbaric oxygen therapy (HBOT)

| Carbon monoxide poisoning and cyanide poisoning

Idarucizumab

| Reversal of dabigatran etexilate, an anticoagulant

Insulin + Glucagon

| Beta blocker poisoning and calcium channel blocker poisoning

Leucovorin

| Methotrexate, trimethoprim and pyrimethamine overdose

Intralipid

| Local Anesthetic toxicity

Methylene blue

| Treatment of conditions that cause methemoglobinemia

Naloxone hydrochloride

| Opioid overdose

N-acetylcysteine

| Paracetamol (acetaminophen) poisoning

Octreotide

| Oral hypoglycemic agents

Pralidoxime chloride (2-PAM)

| When given with Atropine: Organophosphate insecticides, nerve agents, some poison mushrooms

Protamine sulfate

| Heparin poisoning

Prussian blue

| Thallium poisoning

Physostigmine sulfate

| Anticholinergic poisoning

Pyridoxine

| Isoniazid poisoning, ethylene glycol, accidental hydrazine exposure (E.G from Gyromitra mushrooms)

Phytomenadione (vitamin K) and fresh frozen plasma

| Warfarin overdose and some (but not all) rodenticides

Sodium bicarbonate

| Aspirin, TCAs with a wide QRS{{clarify|date=August 2019}}

I.V Silibinin

| Amatoxin ingestion

Succimer, chemical name Dimercaptosuccinic acid (DMSA)

| Lead poisoning

See also

References

{{Reflist}}

{{Major drug groups}}

{{Antidotes}}

{{Toxicology}}

{{Authority control}}