Inclusion criteria:
18-65 years old men
With the diagnosis of schizophrenia based on DSM-5 criteria for at least two years and despite the anti-psychotic drug treatment, they are still symptomatic.
They are treated with antipsychotics for at least one year and In the last month, the type and dosage of their antipsychotic drugs remain constant.
If receiving medications such as mood stabilizer or anti depressants, their type and dosage will remain constant from one month before the start of the study and during the study.
Exclusion criteria:
Patients with acute suicidal behavior or history of suicide attempt last year, the presence of psychiatric disorders such as schizoaffective or other psychotic disorders, Mental retardation or other cognitive impairment, bipolar disorder and depression, anxiety disorders such as current panic disorder or obsessive-compulsive disorder, post traumatic stress disorder, eating disorder.
History of drug dependence (DSM-5 drug dependency criterion) or substance abuse during the three months prior to the onset of the study or positive urine specimen testing at the start of the study.
ECT therapy in the past six months.
People with thoughts or attempted to harm themselves or others at baseline and at 6 months before the start of the study.
Mental retardation
Patients with neurological disorders such as uncontrolled seizure, dementia, head injury, seizure disorder (other than febrile) and neurodegenerative diseases (such as Alzheimer's disease, Parkinson's disease, stroke, and multiple sclerosis)
Patients with uncontrolled illnesses such as cardiovascular disease-liver and kidney failure-types of malignancies-autoimmune diseases, endocrine disorders such as diabetes, and hematological disorders, chronic diseases such as cardiovascular disease, history of myocardial infarction, severe hypertension, excessive overweight due to endocrine disorder, unstable thyroid disease, biliary diseases, consuming sex hormones, cerebrovascular diseases, benign prostatic hypertrophy, glaucoma, asthma, COPD, chronic fatigue syndrome, Fibromyalgia and any unstable medical condition. Receiving anticoagulant and antiplatelet treatments or having hemorrhagic risk factors, having an infectious disease during last month, the likelihood of not being able to complete a study because of a serious illness.
No more than once a week to take analgesics and do not use turmeric and curcumin supplements and no use of turmeric in the diet.
Sensitivity to the curcumin plant or any of the available placebo compounds.
History of NMS
Patients treated with anticholinergic drugs (except of biperiden and trihexyphenidyl) according to drugs on the Anticholinergic Burden scale (ACB)