Skin Bumps
Raised spots on the skin with many possible harmless or treatable causes
Quick Facts
- Type: Skin sign
- Common causes: Clogged pores, cysts, infections, allergies
- Usually: Harmless and treatable
- Check with a doctor: Bumps that grow, bleed, or change
Overview
Skin bumps are raised areas on or just under the skin. They can be tiny or large, soft or firm, single or in clusters, and the same color as your skin or red, brown, white, or skin-toned. The vast majority of skin bumps are harmless and either resolve on their own or respond well to simple treatment.
Bumps appear for many reasons, including blocked pores, harmless cysts, viral or bacterial infections, allergic reactions, and benign growths. The key features that help identify the cause are the bump's appearance, how quickly it appeared, whether it itches or hurts, and whether it is changing over time. Bumps that grow rapidly, bleed, change shape or color, or refuse to heal deserve a professional look.
Where a bump appears also offers clues. Bumps on the face are often related to acne or blocked pores, while clusters on the arms or trunk may suggest insect bites, hives, or a viral rash. A single firm lump under the skin is frequently a harmless cyst or fatty lump, whereas widespread bumps that appear suddenly and itch are more typical of an allergic reaction. Most of the time, simple observation and basic care are enough.
Common Causes
Common reasons for skin bumps include:
- Clogged pores and acne: Blocked oil glands produce pimples, whiteheads, and blackheads.
- Cysts: Fluid- or keratin-filled sacs under the skin that feel smooth and movable.
- Infections: Folliculitis, boils, warts, and molluscum contagiosum cause raised, sometimes tender bumps.
- Allergic reactions: Hives appear as itchy, raised welts; contact dermatitis can cause bumps and blisters.
- Benign growths: Skin tags, moles, lipomas, and keratosis pilaris are common and usually harmless.
- Insect bites: Raised, itchy bumps that often appear in groups.
Associated Symptoms
The symptoms accompanying a bump help point to the cause:
- Itching, common with hives, eczema, and insect bites
- Pain, warmth, or pus, suggesting infection such as a boil
- Redness or a spreading rash around the bump
- Fever or feeling unwell, which can accompany a serious skin infection
- Changes in size, color, or shape over weeks, which warrant evaluation
A bump that is firm, growing, irregularly shaped, or bleeding should be checked to rule out skin cancer.
Diagnosis & Evaluation
Most skin bumps are diagnosed by appearance and a simple history. A clinician will ask how long the bump has been present, whether it has changed, and whether it itches, hurts, or bleeds.
- Visual exam: Inspecting the bump's color, texture, borders, and distribution.
- Dermoscopy: A handheld magnifier to look closely at moles and growths.
- Skin biopsy: Removing a small sample if cancer or an unclear growth is suspected.
- Allergy or infection testing: When hives, eczema, or a specific infection is suspected.
Treatment & Management
Treatment depends entirely on the cause, and many bumps need no treatment at all.
- Acne and clogged pores: Gentle cleansing and topical or oral acne treatments.
- Infections: Antibiotics for bacterial infections; warts and molluscum may be treated or left to clear on their own.
- Allergic bumps: Antihistamines and avoiding triggers for hives; soothing creams for irritation.
- Cysts and benign growths: Often left alone unless bothersome, infected, or growing, in which case they can be drained or removed.
- Suspicious growths: Removal and biopsy when skin cancer is a concern.
Avoid squeezing or picking at bumps, which can cause infection and scarring.
Self-Care & Prevention
- Keep skin clean and moisturized, and avoid harsh scrubbing
- Do not squeeze or pick at bumps
- Use sun protection to reduce the risk of skin growths and cancer
- Identify and avoid known allergens and irritants
- Check your skin regularly and note any bumps that change
When to See a Doctor
See a doctor if a bump is growing, painful, bleeding, not healing, or changing in color or shape. Seek prompt or emergency care for:
- A spreading red, hot, painful area with fever (possible serious infection)
- Rapidly swelling hives with difficulty breathing or swelling of the lips or throat (possible severe allergic reaction)
- A new or changing mole or a sore that will not heal
Difficulty breathing or swelling of the face and throat is a medical emergency — call emergency services immediately.
Frequently Asked Questions
Are skin bumps usually serious?
Most skin bumps are harmless, such as clogged pores, cysts, or benign growths, and either resolve on their own or respond to simple treatment. Bumps that grow quickly, bleed, change color or shape, or do not heal should be checked by a clinician.
What causes small hard bumps under the skin?
Small, firm, movable bumps under the skin are often cysts or lipomas, which are benign. Persistent or growing lumps, or ones that become painful, should be evaluated to confirm the cause.
Why do I have itchy bumps on my skin?
Itchy bumps are commonly caused by hives, insect bites, eczema, or contact with an irritant or allergen. Antihistamines and avoiding triggers usually help, but widespread or fast-spreading hives with breathing trouble need emergency care.
Should I be worried about a bump that does not go away?
A bump that persists for weeks, grows, bleeds, or changes appearance should be examined, as a small number of these can be skin cancer. A clinician may use dermoscopy or a biopsy to check.
When is a skin bump an emergency?
Seek emergency care if hives are spreading rapidly with swelling of the lips, tongue, or throat or difficulty breathing, or if a skin infection is spreading with fever. These can be life-threatening and need immediate treatment.
References
- American Academy of Dermatology Association. Common bumps and growths on the skin.
- MedlinePlus, U.S. National Library of Medicine. Skin lesions.
- Mayo Clinic. Skin cysts and benign growths.
- National Health Service (NHS). Lumps and swellings.