Role of Melatonin With
Antipsychotic Induced Metabolic Effects
The following three randomized, double-blind, parallel-group, placebo-controlled clinical trials evaluated the metabolic effect of melatonin in patients taking antipsychotics.
Study 1: Bipolar Disord. 2014 Jun;16(4):410-21.
- Duration: 8 weeks
- n= total of 44 patients treated with antipsychotics (Second generation): 20 with bipolar disorder and 24 with schizophrenia, randomly received placebo (n = 24) or melatonin 5 mg (n = 20).
- The melatonin group showed a decrease in diastolic blood pressure (5.1 versus 1.1 mmHg for placebo, p = 0.003) compared to placebo group.
- The melatonin group showed a decrease in attenuated weight gain (1.5 versus 2.2 kg for placebo, F = 4.512, p = 0.040) compared to the placebo group.
- This beneficial metabolic effects of melatonin on fat mass (0.2 versus 2.7 kg, respectively, p = 0.032) and diastolic blood pressure (5.7 versus 5.5 mmHg, respectively, p = 0.001) were observed in the bipolar disorder and not in the schizophrenia group.
- No adverse events were reported.
Study 2: J Psychiatr Res. 2014 Jun;53:133-40.
- n= 48 patients with first-episode schizophrenia who were eligible for olanzapine treatment
- Patients were randomly assigned to olanzapine plus either melatonin 3 mg/day or matched placebo
- Duration: eight weeks.
- At week eight, melatonin was associated with significantly less weight gain [mean difference (MD) = 3.2 kg, P = 0.023], increase in waist circumference [MD = 2.83 cm, P = 0.041] and triglyceride concentration [MD = 62 mg/dl, P = 0.090 (nearly significant)] than the placebo.
- Changes in cholesterol, insulin, and blood sugar concentrations did not differ significantly between the two groups.
- Patients in the melatonin group experienced significantly more reduction in their PANSS scores [MD = 12.9 points, P = 0.014] than the placebo group.
- No serious adverse events were reported.
Study 3: Acta Med Iran. 2014;52(10):734-9.
- Design: parallel-group, randomized, double-blind, placebo-controlled trial
- Duration: 12-week
- n = 48 patients: 11-17-year-old adolescents with first time diagnosis of bipolar mood disorder.
- 24 patients were allocated to olanzapine (5-10 mg/day), lithium carbonate (3-4 mg/day), and melatonin (3 mg/day) and
- 24 patients were allocated to olanzapine(5-10 mg/day), lithium carbonate(3-4 mg/day), and placebo.
- Fasting blood sugar showed a greater increase in the placebo group compared to the melatonin group (but this was not statistically significant).
- Mean triglyceride (TG) levels showed a greater increase in the placebo group compared to the melatonin group (but this was not statistically significant).
- Mean cholesterol increased by 24.26 mg/dl in the placebo group compared to 6.84 mg/dl in the melatonin group.
- Mean Systolic Blood Pressure (SBP) increased more slowly in the melatonin group compared with the placebo group (1.05mmHg vs. 6.36 mmHg) (F: 2.32; df: 36; P=0.023).
- Administration of melatonin along with olanzapine and lithium carbonate could significantly inhibit the rise in cholesterol level and SBP compared to placebo.
- The effect of melatonin on TG was more obvious in boys.
- Melatonin was more effective in prevention of SBP rise.
Based on these results: Melatonin 3-6 mg/day can be used as an adjunctive treatment with second generation antipsychotics to reduce the risk of metabolic side effects.
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Dr. Harvinder Singh, M.D. (Admin)
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