Organic Phosphorous Compound and Carbamate Toxicity Medication

Updated: Sep 14, 2021
  • Author: Daniel K Nishijima, MD, MAS; Chief Editor: David Vearrier, MD, MPH  more...
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Medication Summary

Control of clinically significant cholinergic excess is the key to management. Anticholinergic agents can be used to substantially reduce or eliminate the secretory effects of muscarinic excess. Endpoints for therapy include elimination of bronchorrhea (atropine) and improved muscle strength (oximes). Reaching these endpoints may require more medication than commonly prescribed.


GI decontaminant

Class Summary

This drug is used to bind recently ingested agents, thereby limiting systemic absorption. It is not useful for noningestion exposures.

Activated charcoal (Liqui-Char)

Reduces systemic absorption through the alimentary tract. Emergency treatment in poisoning caused by drugs and chemicals. Network of pores present adsorbs 100-1000 mg of drug per gram charcoal. Does not dissolve in water. For maximum effect, administer within 30 min of poison ingestion.



Class Summary

Anticholinergics, such as atropine, cause pharmacologic antagonism of excess anticholinesterase activity at muscarinic receptors. Oximes reverse the inhibition of AChE and nicotinic effects, including muscle paralysis.

Atropine IV/IM (Atropair)

Used for GI or pulmonary distress in known or suspected OP or carbamate poisonings. Continue until bronchoconstriction and bronchorrhea controlled. High doses may be required in first 24 h of treatment. Treatment may be required for 48 h in severe cases. May need to reduce doses with concurrent oximes.

Pralidoxime (2-PAM, Protopam)

Indications include muscle weakness (especially respiratory) in known or suspected OP poisoning. Rarely needed in carbamate poisonings. Muscle strength should increase in 30 min. Must be used early in poisoning, before OP-AChE bond has aged, to be effective. May help prevent intermediate and delayed neuromuscular and neuropsychiatric OP syndromes.



Class Summary

This drug is used to control seizures.

Diazepam (Valium)

Depresses all levels of CNS (eg, limbic and reticular formation), possibly by increasing GABA activity.

Lorazepam (Ativan)

DOC for treatment of status epilepticus because persists in CNS longer than diazepam. Rate of injection not to exceed 2 mg/min. May be administered IM if IV access not available.

Midazolam (Versed)

Alternative to terminate refractory status epilepticus. Because water soluble, takes approximately 3 times longer than diazepam to peak EEG effects. Wait 2-3 min to fully evaluate sedative effects before starting procedure or repeating dose. Has twice the affinity for benzodiazepine receptors than diazepam. May be administered IM if vascular access unavailable.