What causes skin bumps?

Many different diseases, disorders and conditions can lead to a bump or raised surface on the skin, most of which are bothersome but relatively harmless and easily treated. However, depending on the particular characteristics of the abnormal skin area, your doctor may diagnose one of several different diseases, disorders and conditions.

Various causes of skin bumps

Skin bumps can be due to an infection, abnormal growth, or inflammation. There is a wide variety of causes including:

  • Acne

  • Boils (painful red bumps due to a bacterial infection)

  • Cellulitis (an infection of the skin and surrounding tissues caused by a bacterial or fungal infection)

  • Dermatitis or eczema caused by allergy or inflammation

  • Enlarged lymph glands in the neck, groin or armpits

  • Erythema multiforme (a type of allergic reaction)

  • Erythema nodosum (an inflammatory disorder)

  • Folliculitis (infection of a hair follicle)

  • Insect bites

  • Keratosis pillaris (rough, slightly red bumps usually seen on the arms)
  • Lipoma (benign growth of fat cells under the skin)

  • Lyme disease (a bacterial infection)

  • Molluscum contagiosum (a viral infection)

  • Sebaceous cyst (blocked oil gland)

  • Shingles (a viral infection)

  • Warts (rough, hard bumps caused by a viral infection)

Life-threatening causes of skin bumps

In some cases, skin bumps may be a symptom of a serious or life-threatening condition that should be immediately evaluated by a medical professional. In particular, if you suspect an allergic reaction, seek emergency help right away. Serious or life-threatening conditions include:

  • Allergy resulting in hives, swollen tongue, or trouble breathing

  • Kaposi’s sarcoma (a type of skin cancer)

  • Melanoma (a type of skin cancer)

  • Methicillin-resistant Staphylococcus aureus (MRSA) infection

  • Skin cancer (squamous or basal cell carcinoma)

  • Syphilis

Questions for diagnosing the cause of skin bumps

To diagnose the underlying cause of skin bumps, your doctor or licensed health care practitioner will ask you several questions related to your symptoms. You can best help your health care practitioner in diagnosing the underlying cause of your skin bumps by providing complete answers to these questions:

  • Describe the skin bumps. Where are they? What do they look like? When did they appear?

  • What other symptoms are you having?

  • Have you been in recent contact with any unusual or new substances or environments, such as poison ivy, new medications or food, or travelling outside the United States?

Provide your full medical history, including all medical conditions, surgeries and treatments, family history, and a complete list of the medications and dietary supplements that you take.

What are the potential complications of skin bumps?

The complications of an undiagnosed or untreated skin bump or lump depend on the underlying disease, disorder or condition. Skin bumps due to a serious allergic reaction, infection, or cancer can result in death if left untreated.


  1. Get the Skinny on Skin Disorders. Healthline. http://www.healthline.com/health/skin-disorders.
  2. Erythema nodosum. Dermatology Online Journal.  http://dermatology.cdlib.org/DOJvol8num1/reviews/enodosum/requena.html.
  3. Skin rashes and other changes. American Academy of Family Physicians.  http://familydoctor.org/online/famdocen/home/tools/symptom/545.html.
  4. Ferri FF (Ed.) Ferri’s Fast Facts in Dermatology. Philadelphia: Saunders Elsevier, 2011.

What are skin bumps?

Skin bumps refer to any type of swollen area or lump on the skin that can occur with or without itching. The bump may be smooth or rough, hard or soft, and light or dark colored. You may have a single skin bump or several raised areas over any part of the body.

Many different diseases, disorders and conditions can lead to a bump or raised surface on the skin. Infections, injuries,... Read more about skin bumpsintroduction


What other symptoms might occur with skin bumps?

Skin bumps may occur with other symptoms, depending on the underlying disease, disorder or condition. These symptoms can either occur locally at the site of the bump or involve other body systems.

Symptoms that may occur with skin bumps include:

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Sep 30, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Infections and Contagious Diseases, Eczema

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