Nocturnal penile tumescence (NPT) stamp test; Nighttime penile tape test
An erection self-test is a method to determines a man's ability or inability to achieve an erection during sleep.
A strip of four to six postage stamps (any kind) is used for each test. The test needs to be done for 3 nights. The man needs to wear brief-type undershorts that have a fly. Place the penis through the fly, leaving most of the pubic hair against the body.
Wrap the strip of stamps snugly around the shaft of the penis. The stamps need to overlap so the overlapped stamp can be moistened to seal the ring. When the stamp has dried, carefully place the penis back inside the shorts and wear them while sleeping. (They help protect the stamps from falling off).
In the morning, check to see if the stamp ring has been broken along the perforations. If the tearing of the stamps awakens the man during the night, check for an erection and how rigid the erection is.
You will need to buy some stamps. Do not drink alcohol or take a sleep-inducing or sedative medication for at least 2 days before the test.
The stamps may feel unusual. The test should be done until 3 nights of comfortable, uninterrupted sleep is achieved.
The test is done to confirm if a man can have an erection at night. All men with normal physiological erectile function will have an erection during normal sleep. The test may help determine if the cause of erectile dysfunction is psychological or physical.
Lue TF, Broderick GA. Evaluation and management of erectile dysfunction and premature ejaculation. In: Wein AJ, ed. Campbell-Walsh Urology. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 22.
Moore DP, Jefferson JW. Erectile dysfunction. In: Moore DP, Jefferson JW, eds. Handbook of Medical Psychiatry. 2nd ed. Philadelphia, Pa: Mosby Elsevier; 2004:chap 100.
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