In a letter to the editor, a 28-year-old man was taking rivaroxaban 20 mg daily for the treatment of pulmonary embolism in the context of a heterozygous prothrombin gene mutation. [12] The patient was on treatment with oxcarbazepine 600 mg twice daily, gabapentin, and topiramate with diagnoses of schizophrenia, psychosis, bipolar disorder, and depression. The gene discussed is F2; the disease is bipolar disorder.