Systemic lupus erythematosus is a chronic inflammatory condition caused by an autoimmune disease. Systemic lupus erythematosus has been described as inducing neuropsychiatric symptoms, including mania and psychosis, in approximately 14 to 80 percent of systemic lupus erythematosus patients. We present and discuss the differential diagnoses in a patient with mania and systemic lupus erythematosus being treated with immunosuppresants and also with a history of glucose-6-phosphate dehydrogenase deficiency. Finally, we review the potential pathogenesis of mania due to an inflammatory-mediated etiology and how this may be used to partly explain the pathogenesis of primary mood disorders.