Mania in a patient receiving testosterone replacement post-orchidectomy taking St John's wort and sertraline

We describe the case of a patient who developed depression following bilateral orchidectomy for cryptorchidism. He was treated with a conventional selective serotonin reuptake inhibitor antidepressant, but continued to take St John's wort (hypericum) against medical advice. He subsequently developed a manic episode. We discuss postulated modes of action of St John's wort and the possible aetiological importance of testosterone replacement and abnormal gonadotrophin levels in this case.