How to prevent sweat rash

What should you change before you start sweating?

• Wear lightweight, loose cotton clothing, especially in hot or humid weather. Loose cotton gives skin more airflow, which is a more useful dress code than "summer collection."
• Exercise outside during the coolest parts of the day, or move your workout into an air conditioned space.
• Take frequent breaks somewhere cooler if you work or spend time outdoors in the heat.
• Use fans or air conditioning indoors, and take cool showers to remove sweat.
• Remove wet clothing. Avoid excessive layers and clothing that rubs against your skin.
• Keep your bedroom cool and ventilated, and use lightweight bedding. Lightweight bedding traps less heat, even if the duvet would prefer year round employment.

Pay particular attention to cooling if you sweat heavily, have a fever or need bedrest. Some medicines, including beta blockers, clonidine and opioids, can make sweat glands more active. If rashes keep returning, discuss your medicines and sweating with your clinician.1

What if a rash has already started?

1. 1Move somewhere cooler and remove clothing covering the affected area.
2. 2Gently wash the skin with cool or lukewarm water, then pat dry without scrubbing.
3. 3Leave the area uncovered where practical, or wear clean, loose clothing that does not rub.
4. 4Apply a cool damp cloth for relief. If using an ice pack, wrap it in a tea towel and apply it for no more than 20 minutes.
5. 5Limit activities that cause heavy sweating until the rash clears. Pat or tap itchy skin instead of scratching.

Avoid perfumed shower gels and creams, excessive soap, and products that block pores. Creams, ointments and powders can trap sweat and worsen heat rash. For troublesome itching, ask a pharmacist about calamine, antihistamines or hydrocortisone rather than adding products at random. Children under 10 need a doctor's advice before using hydrocortisone.124

How do you prevent sweat rash in babies?

Babies and young children are more prone to heat rash because their temperature control and sweat ducts are still developing. Dress babies in lightweight, soft cotton clothing and avoid too many layers or blankets. Keep loose fabric away from a baby's face. If using a fan, position it far enough away to provide only a gentle breeze. Baby powder does not prevent heat rash; avoid powders, creams and ointments for this purpose.15

When should you get medical help?

Heat rash usually clears within a few days after cooling the skin. See a doctor if it does not improve, keeps returning, becomes painful or causes intense itching. Get assessed for fever, chills, swelling or skin that feels warm around the rash, which can signal infection. Contact your pediatrician if your child's rash lasts beyond a few days, or sooner if you are worried about your baby.146

Confusion, dizziness, nausea or a rapid, strong pulse during heat exposure can signal heat stroke. Get medical help immediately rather than treating these symptoms as just a rash.7