Table 1.

Characteristics of included studies

Study	Methods	Participants	Intervention	Outcome
Deberdt et al. [2005]	Allocation: randomized Blinding: double Duration: 16 weeks (+8 weeks)	Diagnosis: schizophrenia, schizoaffective, schizophreniform and bipolar I disorder N = 125	1. Olanzapine 5–20 mg plus amantadine 100–300 mg daily. N = 60 2. Olanzapine 5–20 mg plus placebo. N = 65	Body weight, BMI, BPRS, MADRS, lipid profile, leptins, insulin, fructosamine, prolactin
Graham et al. [2005]	Allocation: randomized Blinding: double Duration: 12 weeks	Diagnosis: schizophrenia, schizoaffective and bipolar disorder N = 21	1. Olanzapine 5–30 plus amantadine up to 300 mg daily. N = 12 2. Olanzapine 5–30 mg plus placebo. N = 9	Body weight, BMI, PANSS, glucose, insulin, prolactin, lipid profile

BMI, body mass index; BPRS: Brief Psychiatric Rating Scale; PANSS: Positive and Negative Syndrome Scale