Heat bumps, also called prickly heat or heat rash, usually clear up within one to two days once you cool your body down. More severe cases can take a week or longer. The single most effective treatment is getting out of the heat and letting your skin breathe, but several home remedies and over-the-counter products can speed relief and prevent the rash from worsening.
Why Heat Bumps Happen
Heat bumps form when sweat gets trapped beneath the skin instead of evaporating normally. The sweat ducts become blocked, and the sweat leaks into surrounding tissue, triggering inflammation and those characteristic small, raised bumps. Hot, humid conditions are the main trigger, but tight clothing, heavy moisturizers, and anything that prevents airflow over the skin can contribute.
Not all heat bumps are the same. The mildest form produces tiny, clear blisters near the skin’s surface with little to no itching. The most common type, often called prickly heat, involves deeper blockage that causes red, inflamed bumps and a stinging or prickling sensation. A rarer, deeper form can produce flesh-colored bumps and may interfere with your body’s ability to cool itself. Most people deal with the red, itchy variety.
Cool Your Skin First
The fastest way to start healing heat bumps is to lower your skin temperature. Move to an air-conditioned room or a shaded area with good airflow. If you don’t have air conditioning, a fan helps as long as the humidity is moderate (roughly 30 to 50 percent). In very humid conditions above 70 percent, a fan can actually make things worse because sweat can’t evaporate efficiently.
A cool bath or cool, damp compresses applied directly to the rash will draw heat away and help unclog sweat ducts. Wetting your skin with a spray bottle or damp cloth works well too. Research published in the Journal of the Mississippi State Medical Association found that skin wetting and foot immersion in cool water can reduce heat strain even at extreme temperatures. After cooling, dry your skin completely. Moisture left sitting on the surface can keep the ducts blocked.
What to Put on Heat Bumps
Calamine lotion is a go-to option. It soothes itching and has a mild drying effect that helps the rash resolve. Apply a thin layer to the affected area and let it air dry.
Over-the-counter hydrocortisone cream (1 percent) can reduce inflammation and itching. It’s typically applied one to four times per day. If the rash hasn’t improved within seven days of using it, stop and talk to a doctor. Don’t apply it to broken or infected skin.
Anti-itch lotions containing camphor or menthol create a cooling sensation that can temporarily override the prickling feeling. Apply a thin film to the affected area, but avoid using them on broken or damaged skin. These products are generally safe for adults when used for a week or less. For children under two, check with a pediatrician first.
One product worth knowing about: moisturizers with anhydrous lanolin (wool fat). Unlike most moisturizers, which can clog pores and make heat bumps worse, lanolin-based products actually help prevent sweat duct blockage. Avoid oily or greasy lotions, heavy sunscreens, and cosmetics on affected areas, as these trap sweat and slow healing.
What to Wear While Healing
Clothing choices matter more than most people realize. Switch to loose-fitting garments in cotton, linen, or silk. These fabrics allow air to circulate over your skin and wick moisture away. Avoid synthetic fabrics, long sleeves, and anything that clings. If possible, leave the affected skin uncovered entirely to let sweat evaporate freely.
Treating Heat Bumps in Babies
Heat rash is extremely common in newborns and young children, especially in the first few weeks of life. Babies overheat easily, particularly when bundled in layers, wrapped tightly in blankets, or buckled into car seats where airflow is restricted.
Treatment for babies follows the same principles as adults, with a few adjustments. Cool your baby with a lukewarm bath or cool, damp compresses, then dry the skin thoroughly. Leave the rashy areas uncovered when possible. Dress your child in thin, loose cotton clothing that allows airflow but isn’t so loose it could tangle or wrap around them. Use fans or air conditioning to keep the room comfortable.
Contact your pediatrician if the rash doesn’t improve after three days of home treatment, gets visibly worse within 24 hours, looks infected (red, tender, or draining pus), or if your baby develops a fever, eats less, or becomes unusually inactive.
Signs of Infection to Watch For
Most heat bumps are harmless and resolve on their own. But scratching can break the skin and invite bacteria in. Watch for increasing redness that spreads beyond the original rash, swelling, warmth, tenderness, or pus. A foul smell from skin folds is another red flag. These signs suggest a secondary bacterial infection that may need antibiotic treatment, either topical or oral, depending on severity.
Preventing Heat Bumps From Coming Back
Once you’ve had heat bumps, your sweat ducts may be more prone to blocking again for a few weeks. Keep your skin cool and dry during that period. Shower promptly after sweating. Change out of damp clothes quickly. Use lightweight, breathable fabrics and skip heavy skincare products in hot weather. If you exercise outdoors, try to do it during cooler parts of the day and towel off frequently.
In humid climates, air conditioning is the most reliable prevention tool. If that’s not available, positioning a fan to blow directly over exposed skin and periodically misting yourself with cool water can meaningfully reduce your risk.