Case Report Zolpidem at Supratherapeutic Doses can Cause Drug Abuse, Dependence and Withdrawal Seizure

Zolpidem is a non-benzodiazepine hypnotic drug, acts selectively through omega 1 receptors of GABAA. It is thought to be safer than benzodiazepines but we report a case of zolpidem drug abuse, dependence and withdrawal seizure. © was re-instituted in dose of 20mg per day and then gradually tapered over few days during hospitalization. At the time of discharge he was on phenytoin sodium 300 mg per day. DISCUSSION This patient was taking zolpidem frequently for long time and in supratherapeutic doses and he became dependant on it. He had a withdrawal seizure after 48 hours of its abstinence. Other than drug withdrawal there was no other explanation for the seizure. He did not have past history of any seizure and head injury, he was not taking any other drug that could cause seizure, and MRI brain was normal. During withdrawal period he was very restless and required zolpidem again to get relief. This report highlights the fact that zolpidem has drug abuse potential and dependence liability. Sudden withdrawal from supratherapeutic doses may precipitate an epileptic seizure as a part of withdrawal syndrome. The possible explanation is that at supratherapeutic doses it may also act non-selectively to omega 2 receptors of GABAA, like benzodiazepines and may result into withdrawal seizure. On electronic database search we could find only six cases of zolpidem withdrawal seizures.2-7 All the patients were on supratherapeutic doses of zolpidem and were dependant on the substance. The recommended dose of zolpidem for insomnia is 10 mg before going to bed for 7-10 days. This patient was taking 50 to 200 mg of zolpidem every day. In previous case reports of zolpidem withdrawal seizures, supratherapeutic doses ranging from 130 mg to 600 mg per day have been reported.2,3,