Previously published in Examiner
Heat rash known as prickly heat and miliaria is a condition that has been associated with babies who are bundled up too tightly and become overheated. However, adults even in Montreal and the rest of North America can get heat rash as well. Heat rash is a summer time ailment in Montreal and comes with hot and humid weather. Montreal summers are very hot and humid and with the climate change getting worse all the time.
Heat rash happens when perspiration is trapped under the skin and the sweat ducts are blocked. The rash can be blisters or they can be deep red lumps. They can be itchy or prickly; hence the name prickly heat.
Most heat rash goes away in time, though some severe cases will need medical treatment. The best prevention is to keep your body cool so it does not sweat.
The best treatment is to get out of the heat and let your body cool down. Go into an air conditioned building or at least a room with a fan. Wear light clothing such as cotton that allows your skin to breathe. Do not exercise in hot humid weather and try to avoid hard physical work if you can. Stay out of the sun as much as you can. For mild heat rash no other treatment is necessary.
If your heat rash is more severe you may want to try some topical lotions such as calamine lotion for the itch. You can try Anhydrous lanolin to clear the sweat ducts, or topical steroids. Make sure the topical steroid is oil based. a water based lotion will only further clog ducts.
To prevent heat rash stay cool. Do not towel dry but let your skin air dry. Wear light clothes, avoid tight fitting clothes, stay out of the beating sun, try to remain in an air conditioned building or at least one with fans. Do not use lotions and creams, and do not exercise or over exert yourself. If you are outside stay in the shade. When you bath or shower use a nondrying soap that does not contain dyes or perfumes.
Source:
http://www.mayoclinic.com/health/heat-rash/DS01058/DSECTION=complications