Objective: Subsequent to a randomised, double-blind, double dummy clinical trial assessing the efficacy of silexan compared to placebo and paroxetine in patients suffering from generalised anxiety disorder (GAD), a 1week follow-up phase was added in order to assess possible withdrawal symptoms of silexan after abrupt discontinuation.
Methods: Participants received silexan 80 mg/d, silexan 160 mg/d, paroxetine 20 mg/d, or placebo at a ratio of 1:1:1:1. Study medication was discontinued after the 10 week active treatment phase of the original trial. Whereas paroxetine was tapered as indicated, silexan administration was discontinued abruptly. Assessment of possible withdrawal effects was done using the Physician Withdrawal Checklist questionnaire (PWC-20).
Results: During the 1 week down-titration phase, mean total PWC-20 scores had reduced by 0.19 in placebo, 0.23 in silexan 80, 0.65 in silexan 160, and 0.51 in paroxetine. The median change in all four groups was 0.00. In none of the treatment groups withdrawal effects occurred after discontinuation.
Conclusions: Values assessed for the silexan groups indicate the absence of a dependency potential of this preparation.
Keywords: Discontinuation effects; GAD; PWC-20; lavender oil; silexan.