Melatonin and melatonin agonists as treatments for benzodiazepines and hypnotics withdrawal in patients with primary insomnia. A systematic review

Background: Hypnotics (HYP) and benzodiazepines (BZD) are medicines prescribed for the insomnia treatment. Many patients present difficulties in discontinuing the treatment once established. Melatonin (MLT) has been prescribed as a treatment for BZD/HYP detoxification. Aims: The primary objective of this systematic review is to assess the efficacy of MLT and MLT agonists (melatoninergics) in improving the rate of BZD and/or HYP discontinuation among adults with primary insomnia attempting to discontinue BZD and/or HYP. The secondary objective is to evaluate the partial efficacy of melatoninergic drugs in the discontinuation of BZD and/or HYP consumption in subjects that could not stop their consumption. Method: A search on Web of Science and Scopus was carried out from database inception to July 1st, 2019. Results: Three hundred and forty-nine articles were identified but only four were included in the final review. Two were cohort prospective, one placebo-control double blind and one double blind placebo-control cross-over designed study. Total withdrawal (TW) ranged from 0% to 25% in the placebo arm and from 64.3% to 77.8% in the MLT arm. In cohort studies TW figures ranged from 30.8% to 65%. Partial withdrawal ranged between 20% and 30.8% of patients that did not achieve TW with reduction figures of diazepam equivalent dose ranging from 25% to 75%. Conclusion: MLT has a place in the physician armamentarium to treat the suspension/reduction of BZD/HYP consumption in patients with primary insomnia.