Keratosis pilaris is a common cause of bumps on the arm. These bumps are harmless and may look like goosebumps or chicken skin. However, if the bumps are itchy, this may point to eczema, folliculitis, or heat rash.

A person may not need treatment for the bumps on their arms unless they develop any bothersome symptoms, such as dryness or itchiness.

Keep reading for more information about health issues that commonly cause bumps on the arms.

Keratosis pilaris is a common cause of bumps on the arms. This benign skin condition may form dry, rough patches or resemble goosebumps, pimples, or a rash.

These bumps contain extra keratin, which is a protein in the hair, skin, and nails. A buildup of dead skin cells contributes to the issue.

The bumps are usually skin-colored. They may look red on lighter skin or brownish-black on darker skin tones, and they can sometimes be itchy.

A person is most likely to notice the issue when the skin is dry, such as during winter months. The bumps may disappear during warmer or more humid seasons.

In older children and adults, keratosis pilaris typically appears on the upper arms, thighs, and buttocks. In younger children, the bumps usually form on the cheeks, but they can also appear on the arms and thighs.

According to the American Academy of Dermatology (AAD), the condition often develops before a child turns 2 years old or during the teenage years.

About 50–80% of adolescents and at least 40% of adults may have keratosis pilaris. However, these estimates are likely low, as people often do not report the issue to their doctors.

Some factors that increase a person’s chances of developing keratosis pilaris include:

Keratosis pilaris is also associated with diabetes, Noonan syndrome, and malnutrition. It may be a side effect of vemurafenib, a medication that can treat melanoma, too.

A person with keratosis pilaris can take some steps to prevent bumps from forming. The AAD recommends:

  • using a thick, oil-free moisturizing cream
  • moisturizing immediately after bathing, while the skin is still damp
  • using moisturizer whenever the skin feels dry
  • considering hair removal techniques other than shaving or waxing, which can make keratosis pilaris worse
  • limiting showers and baths to once a day and keeping them short
  • avoiding bar soap in favor of a mild cleanser
  • using a humidifier if the skin is dry
  • avoiding self-tanners

While keratosis pilaris is the most common cause of bumps on arms, there are other possible causes.

Itchy causes

  • Eczema can form red, itchy patches or small, liquid-filled bumps that eventually crust over.
  • Heat rash often causes redness, itchiness, or tingling.
  • Folliculitis is the infection of hair follicles, which can form tender, red, pus-filled bumps — typically on areas that are shaved or exposed to frequent irritation.
  • Psoriasis is an inflammatory skin condition in which excessive skin cell growth leads to thick plaques of skin that may be dry, scaly, and raised.
  • Contact dermatitis causes a bumpy rash that can be itchy and otherwise uncomfortable.

Non-itchy causes

Bumps on the arms that are not itchy may point to acne. Acne can cause whiteheads or blackheads, and they develop when a person’s pores get clogged with:

  • dead skin cells
  • bacteria
  • oil

Doctors can recommend some ways to help relieve any itchiness and reduce the bumpiness of the skin.

Exfoliation

The AAD recommends taking the following steps to treat keratosis pilaris:

  1. Gently exfoliate the skin to remove dead skin cells.
  2. Apply a chemical exfoliator, also known as a keratolytic.
  3. Use an oil-free moisturizer liberally.

They also provide the following advice for managing keratosis pilaris:

  • make sure not to scrub the skin harshly
  • use the keratolytic only as directed
  • apply the moisturizer after using the keratolytic, after bathing, and whenever the skin feels dry

Medications

Doctors may prescribe or recommend an over-the-counter ointment or cream that contains one of the following ingredients:

These medications help get rid of dead skin cells. A doctor may also recommend creams or lotions to help with moisturizing the skin.

One study suggests that a combination of natural glycolic acid and salicylic acid may be the best way to restore the skin’s texture. Indeed, 70–80% of participants who used the combination saw smoother skin with less oiliness and a more even texture.

If other treatments fail, a doctor may recommend laser therapy to reduce the bumps and any discoloration.

Only a dermatologist can diagnose the cause of bumps on the arms.

They will ask about general health, family history, and any other symptoms, and examine the affected skin.

For people with any of the following, it may be a good idea to contact a doctor:

  • itchiness
  • dryness that causes discomfort
  • a displeasing appearance of the skin
  • concerns about the underlying cause

It is especially important to receive professional attention if home care techniques are not working.

Also, see a doctor if a rash and a fever are present, as these can be symptoms of a more serious infection.

Below are some commonly asked questions about bumps on arms.

Why might a person be getting bumps on their arms?

A person may be getting bumps on their arms due to the following:

  • keratosis pilaris
  • eczema
  • heat rash
  • folliculitis
  • psoriasis
  • contact dermatitis

What triggers keratosis pilaris?

Keratosis pilaris happens when a person’s hair follicles become blocked with a buildup of keratin, a substance found in skin, hair, and nails. The cause of this is unknown, but researchers believe that families carry the condition.

How can a person get rid of keratosis pilaris on their arms?

A person may be able to get rid of keratosis pilaris by gently exfoliating the skin to remove dead skin cells.

Alternatively, a doctor may prescribe or recommend an over-the-counter ointment or cream that contains ingredients such as lactic acid, salicylic acid, or retinoids.

What can be mistaken for keratosis pilaris?

Keratosis pilaris is a condition where small bumps appear on the skin. It can be mistaken for:

In many cases, bumps on the arms result from keratosis pilaris, a benign condition that usually requires no treatment.

Certain home care techniques can help reduce the bumps and any associated symptoms.

A doctor can recommend professional treatments if these methods are ineffective and the bumps are causing discomfort.