Benzodiazepine Toxicity Medication
- Author: Robin Mantooth, MD, FACEP; Chief Editor: Asim Tarabar, MD more...
GI decontaminant
Class Summary
Empirically used to minimize systemic absorption of the toxin.
Activated charcoal (Liqui-Char)
Most useful if administered within 1-2 h of ingestion. Repeat doses may be used, especially with ingestion of sustained release agents. Limited outcome studies exist, especially when administration is more than 1 h of ingestion.
Administration of charcoal by itself (in aqueous solution), as opposed to coadministration with a cathartic is becoming the current practice standard. Studies have not shown benefit from cathartics, and, while most drugs and toxins are absorbed within 30-90 min, laxatives take hours to work. Dangerous fluid and electrolyte shifts have occurred when cathartics are used in small children.
When the ingested dose is known, charcoal may be administered at 10 times ingested dose of agent over 1 or 2 doses.
Antagonist
Class Summary
Flumazenil is a selective competitive antagonist of the GABA receptor and the only available specific antidote for BZDs; it will reverse effects of BZDs but must be used with caution. If BZDs are being used to treat a potentially life-threatening condition (eg, seizure disorder), antagonists may exacerbate the underlying disorder.
Additionally, co-ingestion commonly occurs with agents that lower the seizure threshold (eg, cyclic antidepressants) and reversal may result in seizure or status epilepticus; therefore, antagonists are not recommended for use by prehospital personnel or for indiscriminate use before a complete evaluation.
In overdose situations, flumazenil may be used for patients with pure BZD overdose who are verbally unresponsive and have no history of long-term BZD use or seizure disorder. Perform an ECG should be performed before use to confirm the absence of cardiac conduction disturbances (which would suggest the presence of cyclic antidepressants). Use as a diagnostic and therapeutic agent for unsubstantiated drug-associated coma is controversial. A positive response to small titratable doses may obviate the need for endotracheal (ET) intubation and the search for other causes of coma.
Flumazenil (Romazicon)
DOC to reverse effects of BZDs in an overdose by selectively antagonizing GABA/BZD receptor complex.
If overdosed patient has not responded after 5 min of 5 mg cumulative dose, cause of sedation is not likely to be BZDs.
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