Don’t use phenytoin or fosphenytoin to treat seizures caused by drug toxicity or drug withdrawal.
|Rationale and Comments:||With rare exceptions, phenytoin is ineffective for convulsions caused by drug or medication toxicity. Phenytoin has been demonstrated to be ineffective for the treatment of isoniazid-induced seizures and withdrawal seizures and may potentially be harmful when used to treat seizures induced by theophylline or cyclic antidepressants. First-line treatment of toxin-induced seizures and withdrawal seizures is benzodiazepines, followed by additional medications that act through agonism at the γ-aminobutyric acid A receptor, such as barbiturates.|
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