Use Of Immediate Release Melatonin In Psychiatry: Bmi Impacts The Daily-Dose

Objective. - There is a growing interest in psychiatry regarding melatonin use both for its soporific and chronobiotic effects. This study aimed to evaluate factors impacting the daily-dose.Methods. - In a university department of psychiatry in Paris (France), we conducted a posteriori naturalistic observational study from April 03, 2017 to January 31, 2018. We assessed links between sociodemographic and clinical characteristics and daily dose of melatonin (the daily-dose of melatonininitiation and the daily-dose at Hospital discharge). A survey of drug interactions was performed regarding metabolic inducers and inhibitors of the cytochrome P450 1A2.Results. - Forty patients were included and treated with immediate-release melatonin. For patients withno history of melatonin use, the initiation dose of was 2 or 4 mg, with no effects of age, weight, BMI, melaton in indication, cause of hospitalization. We found that higher discharge dose was associated with higher BMI (P = 0.036) and more reevaluations of melatonin dose (P = 0.00019). All patients with a moderate inducer (n = 3, here lansoprazole) were significantly more associated with the discontinuation melatonin group (P = 0.002).Conclusion. - The BMI and the number of reevaluations impact the daily dose of melatonin. Two mechanisms may explain that BMI may need higher doses: (i) melatonin diffuses into the fat mass, (ii) thevariant 24E on melatonin receptor MT2, more frequent in obese patients, leads to a decrease of thereceptor signal. (C) 2020 L'Encephale, Paris.