Long-term use of antihypertensive drugs does have an effect on sexual function in some men, such as spironolactone, which can cause gynecomastia, decreased libido, and erectile dysfunction. Other diuretics rarely cause sexual dysfunction. Anti-sympathetic antihypertensive drugs, such as colistin and reserpine, block sympathetic nerves and cause erectile dysfunction. Guanethidine is a peripheral sympathetic blocker that can cause ejaculatory dysfunction in patients. With phentermine and phentolamine, it is possible to experience loss of orgasm. The selective alpha 1 receptor blocker prazosin does not produce ejaculatory dysfunction but can cause poor erectile function. beta-blockers can also cause erectile dysfunction due to decreased libido. Relaxants that act directly on smooth muscle, angiotensin-converting enzyme inhibitors, and calcium channel blockers, do not affect. Patients with chronic hypertension often need higher systolic blood pressure to get blood through the narrow pubic arteries and achieve adequate blood supply. As a result of taking antihypertensive drugs, systolic blood pressure cannot reach the needed height, which may cause poor blood supply erectile dysfunction.