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Studies of cyanide poisoning
Archives Internationales De Pharmacodynamie Et De Therapie
|February 1, 1985
Summary
Amyl nitrite and phenoxybenzamine effectively treat acute cyanide poisoning. Phenoxybenzamine prevents cyanide
Area of Science:
- Toxicology
- Pharmacology
Background:
- Cyanide poisoning is a rapid, life-threatening condition.
- Early mortality is linked to cardiovascular-respiratory failure and cytochrome oxidase inhibition.
Purpose of the Study:
- To evaluate the efficacy of amyl nitrite and phenoxybenzamine in treating acute cyanide poisoning.
Main Methods:
- Anesthetized beagle dogs received intravenous sodium cyanide.
- Hemodynamic, electrocardiographic, respiratory, and methemoglobin levels were monitored.
- Dogs were treated with either phenoxybenzamine (pretreatment) or amyl nitrite (post-treatment).
Main Results:
- Control dogs exhibited severe bradycardia, hypotension, and respiratory paralysis, leading to death.
- Phenoxybenzamine pretreatment prevented cyanide toxicity in 80% of dogs.
- Amyl nitrite administered post-cyanide reversed cardiovascular and respiratory effects in 80% of dogs.
Conclusions:
- Phenoxybenzamine effectively prevents cyanide-induced toxicity when given before exposure.
- Amyl nitrite can reverse established cyanide toxicity, including cardiovascular and respiratory collapse.
- Cyanide's rapid lethality may involve mechanisms beyond cytochrome oxidase inhibition, such as cardiovascular-respiratory failure.
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