SymptomSkin, hair & nails
Red Bumps on the Skin: What They Could Be
Red bumps on the skin are small, raised spots (papules) that are pink or red, sometimes itchy or tender. Most are harmless and short-lived: insect bites, folliculitis (inflamed hair follicles), acne, hives, heat rash, keratosis pilaris and contact dermatitis. The pattern, location and whether they itch usually point to the cause. Red bumps with fever, fast spreading, blisters in the mouth or eyes, or spots that do not fade when pressed need prompt medical care.
Also called: Red spots, red papules, red skin bumps, little red bumps
At a glance
- What they are
- Small, raised red spots, single or in clusters, itchy or not.
- Most common causes
- Insect bites, folliculitis, acne, hives, heat rash, keratosis pilaris, contact dermatitis.
- Itchy clues
- Bites, hives, scabies, eczema and contact dermatitis itch most.
- Non-itchy clues
- Keratosis pilaris, cherry angiomas and acne usually do not itch.
- Red flags
- Fever, rapid spread, blistering, mouth or eye sores, or spots that do not fade under a glass.
When to get help
Call 911 or go to the ER
- Red or purple spots that do not fade when a glass is pressed on them, with fever or feeling unwell (possible meningococcal infection)
- Hives with swelling of the lips, tongue or throat, wheezing or dizziness (possible anaphylaxis)
- Widespread red spots that blister or peel, with sores in the mouth, eyes or genitals (possible severe drug reaction)
See a doctor within a day or two
- A red bump that becomes a painful, hot, swelling lump or has a spreading red area, especially with fever (possible abscess or cellulitis)
- Red bumps with fever in a child who seems unwell, or in someone with a weakened immune system
- A rash after a tick bite, especially an expanding red ring
Book a routine appointment
- Intensely itchy bumps, worse at night, in skin folds, wrists and between fingers, or affecting others at home (possible scabies)
- Red bumps that keep coming back or have lasted more than 2 to 3 weeks
- A single red bump that bleeds, grows or does not heal
Usually safe to manage at home
- A few itchy bumps after outdoor activity or gardening, likely bites
- Small red bumps around hair follicles after shaving or sweating
- Rough, tiny bumps on the backs of the upper arms that have been there for years
How to tell red bumps apart
Look at four things: itch, pattern, location and timing.
| Cause | Itch | What it looks like | Where |
|---|---|---|---|
| Insect bites | Yes | Scattered bumps, sometimes with a central dot | Exposed skin: ankles, legs, arms |
| Bed bug bites | Yes | Lines or clusters of 3 to 5 bumps, appear overnight | Arms, neck, shoulders, face |
| Folliculitis | Mild to moderate | Small red or white-topped bumps around hairs | Thighs, buttocks, beard area, back |
| Acne | Usually no | Pimples, blackheads and whiteheads | Face, chest, back |
| Hives | Very itchy | Raised welts that change shape and fade within 24 hours | Anywhere |
| Heat rash | Prickly | Tiny red bumps in sweaty areas | Neck, chest, skin folds |
| Keratosis pilaris | Rarely | Rough, sandpaper-like tiny bumps | Backs of arms, thighs, cheeks |
| Contact dermatitis | Yes | Red bumps or blisters where skin touched something | Matches the contact area (watch strap, poison ivy lines) |
| Scabies | Intense, worse at night | Tiny bumps and short burrow lines | Finger webs, wrists, waist, genitals |
| Cherry angiomas | No | Bright red, smooth, dome-shaped dots | Trunk; common after 30 |
Common causes in detail
Bites
Mosquitoes, fleas, chiggers, mites and bed bugs cause itchy red bumps. Flea bites cluster around the ankles. Chigger bites appear at sock lines and waistbands. Bed bug bites often appear in rows after sleeping. Most settle in a week.
Folliculitis
Inflamed or infected hair follicles cause small, red, sometimes pus-filled bumps. Triggers include shaving, tight clothing, sweating, and hot tubs ("hot tub folliculitis," from Pseudomonas bacteria, appears 1 to 2 days after soaking). Razor bumps in the beard area are a related problem.
Hives
Hives (urticaria) are raised, itchy welts that come and go, each lasting less than 24 hours. Common triggers are viral infections, foods, medicines and insect stings, but often no cause is found.
Heat rash
Blocked sweat ducts cause tiny, prickly red bumps in hot, humid weather or in babies who are overdressed. It clears within days of cooling down.
Keratosis pilaris
A very common, harmless condition where keratin plugs hair follicles, giving rough "chicken skin" bumps on the upper arms and thighs. It is often worse in winter.
Viral rashes
Chickenpox starts as red bumps that turn into fluid-filled blisters and crusts. Hand, foot and mouth disease causes red spots on the palms and soles with mouth sores. Molluscum contagiosum causes small, firm, pearly bumps with a central dimple.
Other causes
Eczema, pityriasis rosea, psoriasis (guttate type after strep throat), and drug rashes can all cause red bumps. Rarely, a persistent red bump is a skin cancer such as basal cell carcinoma.
Red bumps by location
- Arms: keratosis pilaris, bites, eczema, contact dermatitis.
- Legs: bites, folliculitis from shaving, hives; small red-purple non-blanching spots on the shins need checking.
- Face: acne, rosacea, perioral dermatitis, milia.
- Torso: folliculitis, cherry angiomas, pityriasis rosea, heat rash.
- Buttocks and thighs: folliculitis from friction and sweat.
How doctors diagnose red bumps
Most red bumps are diagnosed by looking at them and asking about itch, timing, new products, medicines, travel, pets, and whether others at home are affected. Occasionally a doctor will take a skin scraping (for scabies or fungus), a swab (for infection) or a small biopsy for unusual or persistent bumps.
Treatment and home care
- Itchy bumps: cool compresses, fragrance-free moisturizer, and an oral non-drowsy antihistamine for hives or bites. Mild 1% hydrocortisone cream for a few days helps bites and contact dermatitis in adults and older children.
- Folliculitis: warm compresses, gentle cleansing with an antibacterial wash, loose clothing, and a break from shaving. See a doctor if it spreads or recurs.
- Heat rash: cool down, wear loose cotton, and avoid heavy creams.
- Keratosis pilaris: moisturizers with urea or lactic acid; it is controlled, not cured.
- Scabies: prescription permethrin cream for everyone in the household at the same time, plus washing bedding and clothes in hot water.
- Bed bugs: treat the bites with anti-itch care; the home needs professional pest control.
- Avoid scratching: keep nails short to reduce infection.
Frequently asked questions
What causes small red bumps that itch?
The most common causes are insect or bed bug bites, hives, eczema, contact dermatitis, heat rash and scabies. Bites appear on exposed skin, hives come and go within hours, and scabies itch most at night in the finger webs, wrists and waist.
What are red bumps on the skin that don't itch?
Non-itchy red bumps are often keratosis pilaris, acne, cherry angiomas or mild folliculitis. Some viral rashes are also not very itchy. A single red bump that grows, bleeds or does not heal after a few weeks should be checked by a doctor.
When should I worry about red bumps?
Seek emergency care for red or purple spots that do not fade under pressure with fever, hives with face or throat swelling, or blistering skin with mouth or eye sores. See a doctor for bumps with fever, rapid spread, painful swelling, or bumps lasting more than 2 to 3 weeks.
How do I get rid of red bumps on my arms?
If the bumps are rough and painless, they are likely keratosis pilaris: moisturize daily with a cream containing urea or lactic acid and avoid harsh scrubbing. Itchy bumps may be bites, eczema or contact dermatitis and respond to anti-itch care and avoiding triggers.
Are red bumps contagious?
Most are not. Bites, acne, hives, heat rash, keratosis pilaris and contact dermatitis do not spread from person to person. Scabies, chickenpox, molluscum contagiosum, impetigo and some forms of folliculitis are contagious through skin contact.
Sources
This guide was written from current patient and clinical guidance, including:
- American Academy of Dermatology: Folliculitis; Keratosis pilaris; Hives
- MedlinePlus: Skin lumps; Rashes
- NHS: Itchy skin; Folliculitis
- CDC: Bed bugs
- Mayo Clinic: Scabies