COMPARATIVE EFFICACY OF DOXYLAMINE (15 MG ) AND ZOLPIDEM (10 MG) FOR THE TREATMENT OF COMMON INSOMNIA - A PLACEBO-CONTROLLED STUDY

A multicenter, randomized, double-blind, three-way parallel-group stud y was conducted to compare the efficacy and safety of doxylamine versu s zolpidem and a placebo for the treatment of common insomnia. Three h undred thirty-eight outpatients of either sex aged 18 to 73 years were included, All patients had insomnia. Patients took 15 mg doxylamine, 10 mg zolpidem, or a placebo in the evening from D1 through D15, then a placebo in the evening from D16 to D22. Efficacy was evaluated mainl y based on Spiegel's questionnaire scores on D1, D15, and D22. Doxylam ine and zolpidem were better than the placebo for all sleep items exce pt <<dreams>>. No differences were seen between doxylamine and zolpide m for the global score or any of the individual items, Global efficacy as rated by the investigator and by the patients was better for doxyl amine and zolpidem than for the placebo, with no significant differenc e between these two drugs. Tolerability was rated <<good>> by 85.6% of patients, and 30.2% of patients had at least one adverse event (with no significant differences between the three groups). Of the 10 patien ts (3.0%) who dropped out of the study because of adverse events, two (1.8%) were on doxylamine, two (1.9%) on the placebo, and six (5.1%) o n zolpidem. Neither of the two active drugs gave rise to withdrawal sy mptoms, and there were no significant differences between the three gr oups regarding the total score or the scores for most of the individua l items of Tyrer's scale. The efficacy of doxylamine in insomnia compa res favorably with that of zolpidem, the reference compound.