Penis

The penis is an external organ of the urinary and reproductive systems. It allows urine to leave the body. It can also become erect during sexual activity and carry semen out of the body during ejaculation.

People naturally differ in penis size, shape, skin colour, foreskin length, and the angle of an erection. These differences are usually part of normal human anatomy. A penis may also be changed by circumcision, gender-affirming care, injury, or other surgery.

The penis is not a disease or diagnosis. However, changes involving it can sometimes point to a skin condition, infection, blood-flow problem, urinary condition, or injury.

Anyone can use the anatomical word penis, regardless of their gender identity. Some people may prefer another term for their own body.

The visible penis has a shaft and a rounded end called the glans. The opening of the urethra is usually at the tip. The urethra is the tube that carries urine from the bladder and semen from the reproductive organs.

In an uncircumcised penis, the glans is partly or fully covered by the foreskin. The foreskin is movable skin that can usually be drawn back once it has naturally become retractable. It should not be forced back, especially in a child.

Inside the shaft are three columns of spongy tissue. Two are called the corpora cavernosa. The third, the corpus spongiosum, surrounds the urethra and forms the glans.

During an erection, nerve signals cause more blood to enter this tissue. Pressure on the veins slows blood leaving, making the penis firmer. Erections may occur with sexual arousal, during sleep, or without an obvious trigger.

Semen contains sperm and fluid from several reproductive glands. Sperm are made in the testicles, not in the penis. During ejaculation, muscles move semen through the urethra and out of the penis. The body normally limits urine flow during ejaculation.

Sensation comes from a network of nerves, particularly around the glans and foreskin. Sensitivity differs among people and can change with age, medicines, hormone treatment, surgery, nerve conditions, or injury.

The penis has roles in urination, sexual activity, and reproduction. A change in urine flow, erections, ejaculation, sensation, skin, or shape may therefore affect several parts of life.

Erection difficulties can sometimes be related to blood-vessel disease, diabetes, nerve conditions, hormone problems, medicines, stress, anxiety, or relationship concerns. One occasional difficulty is common and does not establish a diagnosis. Repeated problems can be discussed during routine care.

Sores, discharge, burning, or new growths may need assessment for a sexually transmitted infection or another skin condition. A test is often needed because appearance alone cannot reliably identify the cause.

Concerns about appearance can also affect confidence and wellbeing. Online images are not a reliable guide to normal anatomy. There is no routine medical need to measure a penis unless a clinician is assessing a specific concern.

Several named conditions and situations can involve the penis:

• Balanitis is inflammation of the glans. Redness, soreness, itching, or discharge can have several causes, including irritation, infection, or a skin condition.
• Phimosis means the foreskin cannot be drawn back. This can be normal in children. In an older person, pain, scarring, infections, or urinary difficulty should be assessed.
• Paraphimosis occurs when a retracted foreskin becomes trapped behind the glans. The swelling can restrict blood flow, so this needs emergency care.
• Urethritis is inflammation of the urethra. Burning during urination or discharge may be caused by an infection, including a sexually transmitted infection.
• Erectile dysfunction means persistent difficulty getting or keeping an erection suitable for sexual activity. It has physical and psychological causes and can often be assessed and treated.
• Peyronie’s disease involves scar tissue inside the penis. It can cause a new bend, narrowing, pain, or difficulty with intercourse.
• Priapism is an erection that lasts too long and does not settle normally. An erection lasting four hours needs emergency treatment, even if it is not painful.
• Penile fracture is a tear in erect penile tissue, often associated with a popping sound, sudden pain, loss of the erection, bruising, or swelling. It is an emergency.
• Penile cancer is uncommon, but a persistent sore, lump, thickened area, bleeding, or skin change needs medical assessment. Many non-cancerous conditions can look similar.

Sudden severe pain, major trauma, heavy bleeding, inability to pass urine, a trapped retracted foreskin, or an erection lasting four hours requires urgent or emergency care.

New but non-severe changes can usually be assessed through routine primary care, a sexual health clinic, or a urology appointment.

You do not need routine scans, blood tests, or measurements for a healthy penis. If you notice a change, record when it began, whether it is getting worse, and whether it affects urination, erections, ejaculation, or sensation. A photograph may help document a changing bend or skin finding, but keep it secure and do not send intimate images unless a healthcare service has provided a safe method.

Wash the outside gently with water. If you use soap, choose a mild, unscented product and stop if it causes irritation. If the foreskin retracts comfortably, gently wash underneath and return it to its usual position. Do not force it.

Arrange routine care for a persistent lump, sore, rash, discharge, unpleasant smell, pain, new curvature, repeated erection difficulty, or altered urine flow. A clinician may offer an examination, urine or swab tests, blood tests, or an ultrasound depending on the concern.

If sexual contact could have exposed you to an infection, a sexual health service can explain which tests are appropriate and when to take them. Condoms reduce, but do not remove, the chance of many sexually transmitted infections.

Do not apply wart treatments, bleaching products, essential oils, or numbing products to penile skin unless they are intended for that area and recommended by a qualified clinician. Do not attempt to straighten, inject, or enlarge the penis yourself.

Is it normal for the penis to curve?

A slight, long-standing curve can be a normal difference. Arrange an assessment if a curve is new, worsening, painful, associated with a hard area, or interfering with sexual activity.

Does penis size affect fertility?

Penis size does not usually determine fertility. Fertility is more closely related to sperm production, sperm movement, ejaculation, and the reproductive health of both partners.

Are small bumps around the glans normal?

Some bumps are normal structures, such as pearly penile papules or visible oil glands. Other bumps may be caused by irritation, infection, or another skin condition. A clinician can assess new, changing, painful, or persistent bumps without relying on photographs found online.

Is circumcision medically necessary?

Circumcision is surgery that removes the foreskin. People may have it for medical, cultural, religious, or personal reasons. It is not automatically required for every penis. A clinician can explain the relevant benefits, risks, and alternatives for a specific situation.

Can masturbation damage the penis?

Masturbation does not usually damage it. Temporary skin irritation or soreness can occur with intense friction. Sudden pain, marked swelling, bruising, bleeding, or a popping injury needs prompt assessment.

Which clinician should examine a concern?

A primary care clinician can assess most concerns. Sexual health clinics provide confidential testing and treatment for possible infections. A urologist specialises in urinary and reproductive organs and may assess structural, erection, foreskin, or injury-related problems.