Antidote Explained

An antidote is a substance that can counteract a form of poisoning.[1] The term ultimately derives from the Greek term φάρμακον ἀντίδοτον (pharmakon antidoton), "(medicine) given as a remedy". Antidotes for anticoagulants are sometimes referred to as reversal agents.[2]

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.[3] 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.[4] 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.[5]

List of antidotes

width=350ptAgentIndication
Used for many oral toxins
Adenosine receptor agonist poisoning
Antimuscarinic drugs (e.g. Atropine)
Theophylline
Calcium chloride[6] Calcium channel blocker toxicity, black widow spider bites
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
Serotonin syndrome
Deferoxamine mesylate
Digoxin Immune Fab antibody (Digibind and Digifab) Digoxin poisoning, Oleander ingestion [7]
Extrapyramidal reactions associated with antipsychotics
Benzodiazepine overdose
100% oxygen or hyperbaric oxygen therapy (HBOT) Carbon monoxide poisoning and cyanide poisoning
Reversal of dabigatran etexilate, an anticoagulant
Beta blocker poisoning and calcium channel blocker poisoning
Methotrexate, trimethoprim and pyrimethamine overdose
Local Anesthetic toxicity
Opioid overdose
Paracetamol (acetaminophen) poisoning
Oral hypoglycemic agents
Pralidoxime chloride (2-PAM)
Heparin poisoning
Thallium poisoning
Physostigmine sulfate Anticholinergic poisoning
Isoniazid poisoning, ethylene glycol, accidental hydrazine exposure (E.G from Gyromitra mushrooms)
Warfarin overdose and some (but not all) rodenticides
Aspirin, TCAs with a wide QRS
Amatoxin ingestion
Succimer, chemical name Dimercaptosuccinic acid (DMSA) Lead poisoning

See also

Notes and References

  1. .
  2. 4899056 . 27330657 . 10.5811/westjem.2016.3.29294 . 17 . 3 . Anticoagulation Reversal and Treatment Strategies in Major Bleeding: Update 2016 . 2016 . Christos S, Naples R . West J Emerg Med . 264–70.
  3. Smith. T. A.. Figge. H. L.. October 1991. Treatment of snakebite poisoning. American Journal of Hospital Pharmacy. 48. 10. 2190–2196. 0002-9289. 1781479.
  4. Web site: Antidote to deadly jellyfish identified using CRISPR. The-Crispr. 2019-05-13. The Crispr. en-US. 2019-08-08.
  5. Neely. G. Gregory. Seymour. Jamie E.. Hesselson. Daniel. Nguyen. David T.. Qiao-Ping Wang. Khuong. Thang M.. Oyston. Lisa. Littleboy. Jamie B.. Manion. John. 2019-04-30. Molecular dissection of box jellyfish venom cytotoxicity highlights an effective venom antidote. Nature Communications. en. 10. 1. 1655. 10.1038/s41467-019-09681-1. 31040274. 6491561. 2019NatCo..10.1655L. 2041-1723.
  6. Web site: Calcium channel blocker poisoning . UpToDate . 2019-07-09.
  7. Web site: Naturally Occurring Cardiac Glycoside Poisoning · California Poison Control System (CPCS).