What is heat rash?
If your baby suddenly develops a bright-red pimply rash on his neck, under his arms, or near the edges of his nappy or underwear, it's probably heat rash. Heat rash, also known as prickly heat or miliaria, can appear when your baby overheats in hot and humid weather.
The rash often appears in folds of your baby's skin and on parts of his body where clothing fits snugly. If your baby wears hats, the rash may even spread across his scalp or forehead.
Is heat rash serious?
No, but it is a sign that your baby is too warm. If you don't take steps to cool him off, he could become ill with heat exhaustion or heat stroke.
If this happens, your baby will be unable to control his body temperature, his body temperature may become much higher than normal and he could become dehydrated.
What causes heat rash?
When it's hot and humid outside, your baby sweats to cool down. If he sweats so much that his skin pores clog and sweat can't get out, heat rash develops. Babies and young children are particularly prone to heat rash because their sweat glands are not fully developed.
Tight or heavy clothing can trap the sweat as well, making the rash worse. A baby can get heat rash from anything that causes him to sweat heavily, such as a high temperature.
Is heat rash painful for my baby?
No, it isn't usually painful, but it can be annoyingly itchy. The intense prickling or stinging sensation may be distressing for your baby. Some of the pimples may also be tender to the touch.
How should I treat heat rash?
Most heat rashes will clear up within a few days. In the meantime, here's what you can do to relieve your baby's itching and discomfort:
Try to reduce heat and humidity.
Move into an airy room or a shady spot. Try using a mini fan if you are out and about in a hot country or in the summer heat. If the weather stays hot at night, place a fan in your baby's room to circulate the air.
Take off his clothes or dress him in cotton. Synthetic fabrics, such as polyester and nylon, trap heat. Opt for natural fibres instead. Where possible, loosen or remove his clothing and give him as much nappy-free time as you can.
Keep his skin cool.
Cool the affected areas directly using cold, wet flannels, or give your baby a tepid bath or shower. Let the air dry his skin as much as possible rather than using towels. This can help to heal the rash.
Use calamine lotion.
Smooth on plenty of the lotion (but not near his eyes). This is particularly helpful if your baby seems irritable and cries when you touch his skin.
Use hydrocortisone cream.
Use this cream on the advice of your doctor or pharmacist if the rash is severe.
Don't use any other ointments and lotions, as they can make the rash worse by trapping moisture in the skin.
Keep an eye on your baby during this time. As his temperature drops, he could get chilly and need to be warmed up again.
How can I prevent heat rash?
Keep your baby comfortably cool by dressing him in loose, light, cotton clothing, particularly in warm weather.
If you aren't sure whether he's overheated, touch his skin. Damp hot skin is a sign that he is too warm. On a hot day, keep your baby inside or look for cool, shady or breezy places to sit and play outside. Make sure your baby drinks plenty of fluids so he doesn't get dehydrated.
Should I take my baby to the doctor for heat rash?
See your doctor if:
-your baby has a fever
-the rash doesn't go away after three days or four days
-the rash appears to be getting worse.