In some people, the penis can change color when they are aroused, becoming more pink, red, or purple due to increased blood flow. However, penis discoloration can also be a symptom of medical conditions.
Changes in color of the skin on the penis could be a result of skin conditions, infections, or injury.
Read on to learn the possible causes of penis discoloration, their treatments, and when to contact a doctor.
The use of binary terms such as “male” and “female” or “men” and “women” in this article reflects the language of the sources we have used. Unless otherwise noted, it is unclear whether the research we reference included participants with expansive gender identities.
It is typical for the penis to change color during arousal. When a person has an erection, more blood flows to the penis, which can result in the penis having a reddened or darker appearance.
However, if a person notices a change in colour independent of arousal, there are many potential explanations. These include:
Bruising and injuries
Bruising occurs when small blood vessels rupture, leaking blood under the skin’s surface. Where the blood collects, it causes the skin to change color. This can happen anywhere, including on the penis.
Some potential causes of injuries to the penis include:
- sex
- masturbation
- catching the skin in a zipper
- accidents while using machinery or while driving
According to the American Urological Association, the most common cause of penis injuries is sex. Injuries to the penis when it is not erect are less common, as it is soft and more flexible in this state.
Small bruises do not necessarily require particular attention, but if a person experiences any of the following, they should seek medical attention:
A large area of red or purple discoloration could be a hematoma, a collection of blood under the surface of the skin. Hematomas require immediate medical attention since they can cause a loss of blood flow.
A popping sound may indicate a penile “fracture”, which occurs due to tears in tissue known as the tunica albuginea.
STI
Some sexually transmitted infections (STIs) may cause penis discoloration. A person with an STI may notice:
Other potential symptoms of an STI include:
- itchiness
- pain or burning
- pain when urinating
- discharge
People with any of these symptoms should speak with a doctor or visit a sexual health clinic. They will be able to determine if an STI is the cause and recommend the right treatment.
Until a person knows if they have an STI, they should refrain from having sex. This includes oral sex.
Purpura
Purpura, or blood spots, appear as purple or reddish blemishes on the skin. These spots are not a direct result of an injury to the penis. Instead, purpura are often the symptom of an underlying condition.
Some possible causes of purpura include:
- bleeding or clotting issue
- nutritional deficiencies
- medication side effects
- inflammation of the blood vessels
Some causes of purpura require no treatment, while others do. A doctor will recommend treatments based on the underlying cause.
Balanitis
Balanitis is inflammation of the head of the penis. It may cause the head of the penis to look red, though this may be less apparent in darker skin tones.
Other symptoms include:
- itchiness
- soreness
- pain when urinating
- bleeding around the foreskin
- difficulty pulling back the foreskin
- discharge
- an unpleasant smell
Balanitis often occurs due to an infection, but it can also happen if a person does not wash the penis regularly, or if they have an STI or skin irritation. Diabetes can also lead to balanitis if there are high levels of sugar in the urine or blood.
Depending on the cause, a doctor may prescribe an antibiotic, antifungal, or corticosteroid cream to treat it.
Lichen sclerosus
Lichen sclerosus is a chronic skin disorder. When it affects the penis, it causes hardened, blanched patches of skin near the tip. Doctors may also refer to it as balanitis xerotica obliterans.
People who have not undergone circumcision are more likely to develop lichen sclerosus.
Lichen sclerosus, if left untreated, can lead to sexual dysfunction and severe scarring. Early treatment can help prevent permanent damage and scarring.
Cancer
- areas of thickened skin
- a lump or sore
- small crusty bumps
- flat brown or blue growths
- a velvety rash under the foreskin
- discharge or bleeding under the foreskin
There is usually no pain with penile cancer, but there can be. Treatment may include surgery, radiation, or chemotherapy.
A person should contact a doctor as soon as they can if they notice any changes in their penis’s color. Other symptoms to contact a doctor about include:
- bumps, blisters, or sores
- discharge
- swelling
- painful urination
- pain during sex
A doctor will likely perform a physical exam and ask questions about a person’s medical history. They may also run some tests to help determine the exact cause of the symptoms.
While some may feel embarrassed speaking with a doctor, it is important not to delay. A doctor can rule out serious conditions such as cancer and identify the underlying cause, or provide reassurance if the color of the penis is typical.
The sooner a person can get medical care, the sooner they may begin to feel better.
Seek emergency medical attention if a person has an injury to the penis that causes a hematoma, significant swelling, blood in the urine, or a popping sound.
Penis discoloration has several potential causes, ranging from bruising and injury to infections. Rarely, the cause could be cancer.
People should consult a doctor if they notice penis discoloration, especially if they have other symptoms too. The earlier the diagnosis, the sooner people can get treatment.