[Dependence on zolpidem: a report of two cases]

Zolpidem is a sedative and hypnotic drug belonging to imidazopyridine family. Zolpidem facilitates GABAA function more selectively than benzodiazepines, and produces a selective hypnotic effect. In comparison with benzodiazepines this mechanism could be reduce liability to induce dependence. Recently, some cases of zolpidem abuse and dependence have been published. The Authors report 2 cases of addiction to high dose of zolpidem and compare them with others described in the literature. Both patients had been reknown drug addicts before their first prescription of zolpidem and a borderline personality disorder was diagnosed. The patients rapidly developed over consumption and dependence of the molecule, when taking doses as high as 240 and 400 mg daily. To get zolpidem, one patient falsifies prescriptions. They don't suffer from the sedative effects while searching for anxiolytic and stimulating effects. They were also dysarthric, confused, high energy for mental and physical activity. The cases of zolpidem abuse and dependence in the literature describe these symptoms and others such as losing sense of orientation in time and space, amnesia and visual hallucinations. The most typical withdrawal symptom is high levels of anxiety. Moreover, one patient presents an epileptic seizure whereas the other display a severe psychiatric complication such a psychosis. In the literature, withdrawal was accompanied by confusion, suicidal ideas, nausea, vomiting, sweat, tremors, tachycardia and insomnia rebound. The epileptic seizures are described but acute psychosis complication is rare. Pharmacological hypotheses are described. The effects of zolpidem on GABAA receptor gene expression are consistent with the reduced tolerance liability of this drug as well as with other ability to induce both physical dependence and withdrawal syndrome. Through the review of the literature, the Authors noted that 50% of the cases of dependence on zolpidem are drug addicts, therefore concluding that drug addicts are more likely to become dependent on zolpidem.