Olanzapine Orally Disintegrating Tablets Result in Less Weight Gain Compared With Olanzapine Standard Oral Tablets

BACKGROUND: Antipsychotic-induced weight gain may result in obesity. Olanzapine is associated with substantial weight gain. Several studies evaluated whether olanzapine orally disintegrating tablets (OODT) resulted in less weight gain or weight loss compared with treatment with standard olanzapine tablets (SOT). METHODS: Following PRISMA guidelines, we performed a meta-analysis of randomized controlled trials (RCTs) and observational studies that evaluated treatment with OODTs, regardless of psychiatric diagnosis. PubMed and Embase, databases were searched. The primary outcome measure was the change in body weight. RESULTS: Only 10 studies could be included in the meta-analyses. Five were RCT's. Three studies included antipsychotic (AP) naïve patients and 7 studies included an intervention group with patients who switched from SOT or another AP to OODT (AP-switch studies). In all included studies the control group used SOT. In AP-naïve patients, SOT was associated with clinically relevant weight gain and significantly more than OODT (difference of 2.13 kg). Although OODT showed substantial weight gain (3.10 kg) as well. In the switch studies OODT showed some weight loss (-0.61 kg) compared with those who remained on SOT with statistical significant difference (1.97 kg). CONCLUSIONS: We found evidence that starting OODT results in less weight gain compared with SOT, although for both weight gain is substantial. Moreover, switch to OODT may result in weight loss in those who suffer from weight gain by SOT. Although the effects are small, treatment with OODT may be considered as an option for antipsychotic-naïve patients or switch strategy for reaching weight loss.