The penis is the male reproductive organ. It contains a tube (the urethra) that carries urine from the bladder to the outside. During sexual excitement the shaft of the penis, which is normally soft (flaccid), becomes straight and hard (an erection) due to blood that fills two cylinder-shaped bodies (the corpora cavernosa) in the shaft. At the height of sexual excitement (orgasm) the male seed (semen) is squirted through the urethra (ejaculated). The head of the penis (the glans) is normally covered with a sleeve of foreskin (prepuce). The procedure in which the foreskin is cut off is known as circumcision.
Possible causes of pain in the penis
- Infection of the bladder tube (urethritis) causes pain while passing urine, and there may be fluid (a discharge) dripping from the opening at the tip of the penis. Urethritis is often due to a sexually transmitted infection (venereal disease). It may lead to pus formation (an abscess) in the shaft of the penis, which causes severe pain and swelling.
- A painful sore (ulcer) on the head of the penis or on the foreskin is often due to a sexually transmitted infection and often occurs together with urethritis.
- Infection caused by germs in the bladder (cystitis) may cause pain in the penis.
- Infection or inflammation in the prostate gland (prostatitis) may cause pain, especially during ejaculation.
- Stones in the bladder or in one of the tubes carrying urine from the kidney to the bladder (the ureters) can cause referred pain in the penis.
- Infection of the glans (balanitis), foreskin (phimosis) or both (balano-posthitis) will cause pain, itching and redness of the tip of the penis. It is often due to a fungus infection (Candida) which is passed between the man and his sexual partner. It may be a sign that the man has sugar in the urine due to diabetes mellitus.
- When the foreskin is too tight to be pulled back over the glans, it is known as phimosis. This is very common in boys under the age of six, but in older boys the prepuce should be easily retractable. If not, it can predispose to painful infection of the glans and foreskin (balano-posthitis) because germs and fungi find it easier to grow in the warm, moist environment under the foreskin.
- Sometimes the foreskin can be pulled back, but it is relatively tight, and when it becomes trapped behind the glans, especially during an erection, it blocks the veins and causes the tip of the penis to swell up. The glans becomes too swollen (edematous) to pull the foreskin back over it. This is known as paraphimosis, and is very painful.
- Injury (trauma) of the penis will cause pain, and may be due to animal or human bites, knife or gunshot injury, or getting the penis caught in a zipper or some type of machinery. With phimosis, the tight foreskin may be injured during sexual intercourse, which causes pain and bleeding from small tears in the foreskin.
- Cancer of the penis is more common in men with phimosis than in those who had a circumcision. With phimosis, the cancer remains invisible under the foreskin until it starts to cause pain, bleeding and a foul-smelling discharge.
- Pain in the penis during erection may be due to Peyronie's disease. This is caused by buckling of the penis during vigorous sexual activity, leading to small tears and bleeding with eventual scar formation in the corpora cavernosa. After a few months of experiencing pain during intercourse, the man may notice that the penis is becoming bent (curved) during erection. When the penis is soft, it may be possible to feel a hard lump (a plaque of scar tissue) in the shaft.
- A painful erection that lasts for more than 4 hours is known as priapism (named after the Greek god of fertility, Priapus, who had a permanent erection). There are many causes of priapism, but if it is not treated quickly, it may lead to permanent impotence (loss of the ability to get erections).
- Fracture of the penis may occur during vigorous sex, when the erect penis is sharply bent and the wall of one of the corpora is torn. The man may hear a snapping sound, there is sudden, severe pain, the erection goes away immediately and the penis becomes swollen and painful.
- Strangulation of the penis occurs when a ring of some sort is placed around the shaft, usually in an attempt to make erection last longer. The ring blocks the veins draining the penis and leads to swelling and severe pain. If not immediately removed, the ring can cause death of the penile tissues (gangrene).
- Patients with impotence can be treated with an injection into the penis (e.g. prostaglandin E or papaverine) which may cause painful priapism.
- A penile prosthesis consists of two silicone cylinders which are implanted into the penis to provide an artificial erection in someone who has impotence. If the prosthesis is too large or becomes infected, it can cause pain.
- Clotting (thrombosis) in one of the veins in the skin of the penis (Mondor's disease) is a rare cause of penile pain.
Homecare / Self-treatment
Pain in the penis very often indicates that there is something seriously wrong. It should never be ignored or treated with home remedies.
When to see a doctor
If the penile pain is sudden and severe, you should see a doctor immediately. Even if the pain comes on gradually and is bearable, you should nonetheless see a doctor as soon as possible.
What to expect at the doctor
The doctor will ask you questions about your sex life. You should be completely truthful. The doctor will not judge or condemn your sex life, but if you do not tell the truth, it may mislead him into making the wrong diagnosis. He will examine your penis and may also do a rectal examination, and you may be referred to a specialist who deals with penile problems (a urologist).
Infections are treated with antibiotics, anti-fungal or anti-viral drugs or ointment. If there is a sexually transmitted disease, it is extremely important that both partners are treated. Phimosis, paraphimosis and recurrent balano-posthitis are usually treated with circumcision. Peyronie's disease can be treated with different types of drugs or surgery. Priapism, injury or fracture of the penis, and bladder or ureteric stones are usually treated with surgery.