Artemisinin to Reduce The Symptoms of Schizophrenia

Inclusion Criteria * Age 18-65 years old. * Capacity for written informed consent. * Primary Axis I diagnosis (DSM-IV) of schizophrenia, any type, OR schizoaffective disorder (APA, 1994). * Currently an outpatient at the time of enrollment. * Residual psychotic symptoms which are at least moderately severe as evidenced by one or more Positive and Negative Syndrome Scale (PANSS) positive symptom scores, and/or PANSS negative symptom scores of 4 or more; OR a total PANSS score of 50 or more, containing at least three positive or negative items with scores of 3 or more at screening. * Conformance to Patient Outcome Research Team (PORT) Treatment Recommendation #5, Maintenance Antipsychotic Medication Dose (Lehman et al., 2004). * Receiving antipsychotic medication for at least 8 weeks prior to starting the study with no medication changes within the previous 21 days. * Participants must be proficient in English. Exclusion Criteria * Diagnosis of mental retardation. * History of IV drug use. * Any serious medical condition that affects brain or cognitive functioning (e.g., epilepsy, serious head injury, brain tumor or other neurological disorder). * HIV infection or other immunodeficiency condition. * Primary diagnosis of substance abuse or dependence according to DSM-IV criteria within the last three months. * Participated in any investigational drug trial in the past 30 days. * Pregnancy or planning to become pregnant during the study period. * Any clinically significant or unstable medical disorder as determined by the investigators that would preclude study participation, including congestive heart failure, abnormal liver function or disease, renal failure, and any diagnosis of cancer undergoing active treatment.