• 
• 

Three Part Question

In [adult patients who develop seizures following tricyclic antidepressant overdose] does [the use of [benzodiazepines] lead to [safe and effective termination of seizures]?

Clinical Scenario

A 25 year old male arrives to the emergency department following Tricyclic antidperessant overdose. He is drowsy upon arrives and soon after develops a grand mal seizure that lasts over five minutes. You wonder whether benzodiazepines are a safe and effective treatment for the seizures in the specific situation of tricyclic antidepressant overdose.

Search Strategy

MEDLINE 1950 - May Week 2, 2008 using the Ovid interface
EMBASE 1980 - 2008 Week 21 using the Ovid interface
[exp Antidepressive Agents, Tricyclic/ or tricyclic.mp. or amitriptyline.mp. or exp Amitriptyline/ or desipramine.mp. or exp Desipramine/ or clomipramine.mp. or exp Clomipramine/ or doxepin.mp. or exp Doxepin/ or dothiepin.mp. or exp Dothiepin/ or imipramine.mp. or exp Imipramine/ or lofepramine.mp. or exp Lofepramine/ or nortriptyline.mp. or exp Nortriptyline/ or trimipramine.mp. or exp Trimipramine/] AND [exp Benzodiazepines/ or exp Diazepam/ or exp Clonazepam/ or exp Midazolam/ or exp Temazepam/ or exp Nitrazepam/ or (benzodiazepin$ or diazepam or clonazepam or nitrazepam or clonazepam or midazolam or temazepam).mp.] AND [exp Overdose/ or exp Poisoning/ or overdose.mp.] limit to humans and English language

Search Outcome

1154 papers were identified using Embase and 186 using Medline. None were relevant to the three-part question.

Comment(s)

There were no studies found that were relevant to the three part question. Notably there have been no reports of harmful interactions when benzodiazepines are used in tricyclic antidepressant overdose. The National Poisons Information Service recommend the use of intravenous benzodiazepines to control seizures associated with tricyclic antidepressant overdose (http://www.spib.axl.uk).

Clinical Bottom Line

There is no evidence of benefit or harm when benzodiazepines are used to control seizures associated with tricyclic antidepressant overdose. As there is no evidence of harm National Poisons Information Service guidance, which advocates the use of benzodiazepines in this situation, ought to be followed.