Probiotics to Prevent Relapse After Hospitalization for Mania

Inclusion Criteria: * Age 18-65 * Capacity for written informed consent * Currently admitted to a Sheppard Pratt inpatient or day hospital for symptoms of mania * Primary Axis I diagnosis (DSM-IV) at time of admission of Bipolar I Disorder (single manic episode, most recent episode manic, or most recent episode mixed) OR Schizoaffective Disorder, Bipolar type (manic or mixed state) * Proficient in the English language * Available to come to Sheppard Pratt Towson for follow-up visits * Participated previously in one of our screening studies Exclusion Criteria: * Diagnosis of mental retardation * Symptoms of mania secondary to a general medical condition * Any clinically significant or unstable medical disorder as determined by the investigators including congestive heart failure, abnormal liver function or disease, renal failure, acute pancreatitis, any diagnosis of cancer undergoing active treatment, HIV infection or other immunodeficiency condition * History of IV drug use * Primary diagnosis of substance abuse or dependence according to DSM-IV criteria within the last 3 months, or has a positive drug toxicity screen * Participated in any investigational drug trial in the past 30 days * Pregnant or planning to become pregnant during the study period * Receipt of antibiotic medication within the previous 24 hours (as anaerobic organisms residing in the gastrointestinal tract may be minimally affected by antibiotics) * Documented celiac disease (as such persons should be on a gluten-free diet as this is the standard care). Of note, we are not limiting the study to individuals with elevated levels of gliadin or casein antibodies as we intend to look at these levels as a predictor of response.