Comparison of the efficacy, safety and withdrawal of alpidem and alprazolam in anxious patients

Background. We investigated whether a new non-benzodiazepine anti-anxiety drug, alpidem, produces weaker withdrawal symptoms than alprazolam. Method. Under a double-blind procedure, 122 patients suffering from general anxiety disorders were randomly allocated to either alpidem (50 mg, three times a day) or alprazolam (0.5 mg, three times a day) for six weeks, followed by a two-week placebo withdrawal phase. The diagnosis of withdrawal syndrome (WS) was made, in blind conditions, on the basis of the Withdrawal Symptom Check List (WSCL), after one or two weeks of discontinuation of active treatment. Results. The WS occurred significantly less frequently in the alpidem group (n=10, 18%) than in the alprazolam group (n=26, 48%)