3-Quinuclidinyl Benzilate Poisoning Medication
- Author: Christopher P Holstege, MD; Chief Editor: Robert G Darling, MD, FACEP more...
Medication Summary
No specific antidote has been found to reverse the action of QNB definitively. In the past, physostigmine was used to reverse the effects of anticholinergic agents. However, numerous adverse effects associated with its use in reversing poisonings are reported in the literature. Subsequently, the use of physostigmine has diminished greatly in the setting of acute anticholinergic toxicity. Use of physostigmine in QNB poisoning has been studied. However, its efficacy in QNB intoxication and its adverse effect potential have not been delineated definitively. At this time, supportive care is the mainstay of therapy. If the exposed patient is markedly agitated, consider administration of a benzodiazepine.
Benzodiazepines
Class Summary
Consider in patients sustaining exposure to QNB and presenting with marked agitation.
Diazepam (Valium, Diastat)
Depresses all levels of CNS (eg, limbic and reticular formation), possibly by increasing activity of GABA. Induces sedation and helps cease seizure activity.
Antidote, anticholinergic agents
Class Summary
These agents prolong the central and peripheral effects of acetylcholine.
Physostigmine
Inhibits destruction of acetylcholine by acetylcholinesterase, which facilitates transmission of impulses across myoneural junction.
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