Obsessive-compulsive symptoms are a common feature of schizophrenia, and high rates of obsessive-compulsive disorder (OCD) have been reported in schizophrenic patients. Effective pharmacotherapeutic options are available for both OCD and schizophrenia, and for some patients combining medications targeted at both conditions may be a helpful strategy. In combination treatment, consideration needs to be given to the potential for drug interactions. Clinicians treating these disorders should also be aware of the possibility of a worsening of obsessive-compulsive symptoms in schizophrenic patients treated with atypical antipsychotic medications. In this article, pharmacological treatment outcome studies for OCD and schizophrenia will be reviewed, as will the pharmacological treatment of Sam.