A case of unilateral adrenal medullary hyperplasia is presented in a 49-year-old caucasian female without multiple endocrine neoplasia association. The patient presented with episodic hypertension and paroxysms suggesting an underlying phaeochromocytoma. Biochemical supported this diagnosis but no discrete tumour was found on preoperative localising studies or at the time of surgery. The patient underwent a unilateral adrenalectomy with confirming adrenal medullary hyperplasia with complete resolution of her symptoms for six months.