Prickly heat, also called miliaria, appears as tiny red bumps on the skin in defined areas. It is caused by the tiny sweat glands becoming blocked by profuse sweating. This problem is common in people exposed to long periods of heat and can develop as the result of high fevers.
This rash is itchy and uncomfortable, but it does not generally pose a health risk on its own. Miliaria profunda, however, can be dangerous, since it completely blocks the sweat glands and can significantly increase heat related illnesses, such as heat exhaustion or sunstroke. Additionally, the bumps or blisters may become infected if they are scratched. This can cause more serious illnesses, like blood infections, which require antibiotics for treatment. At the very least, scratching the rash will only make it itch more.
In most cases, the treatment for prickly heat is simply staying out of the heat when possible. Showering several times a day when exposure to heat is unavoidable can also help clear the sweat glands. As the skin grows naturally, the rash will eventually be relieved on its own, in most cases, because the ducts eventually clear themselves.
Often, prickly heat develops on the body in areas with a high number of sweat glands or where skin overlaps. It can be show up on the groin, under the knees, in the underarms, or elsewhere. Using antiperspirant may help control the problem under the arms, but it is not recommended for other parts of the body.
This condition can also be a problem for infants during hot weather, and they are most likely to develop it in the diaper area. Allowing babies to spend a bit of time outside of their diapers, perhaps on a few puddle pads to reduce mess, can be a good way to help clear such rashes. Changing diapers frequently can also help, as can using cloth diapers. Long exposure to urine or fecal matter can further irritate the skin and may result in infection.
Both calamine lotion and oatmeal baths may provide relief to the itchy rash. After baths or showers, people should make sure to completely dry the skin in a gentle fashion. Standing in front of a gently blowing fan can help dry the body without causing friction. Very simple soap or medicated soap, which will not dry or irritate the skin more, should be used sparingly.
People can also use powder after showers to reduce sweating. Talc is often recommended, but it can clog the skin and may be dangerous if inhaled. Some health professionals recommend using cornstarch instead, since it provides the same benefits.
Wearing certain types of clothing may also help prevent or relieve prickly heat. Fabrics that retain heat, like nylon and polyester, should be avoided, as should silk, as it tends to provoke more sweating. Linen and cotton are the best options.
Should these rashes get worse and fail to clear up within a few weeks, sufferers should seek the advice of a medical professional to determine if there is an infection. If the person has a fever or if the rash gets worse, he or she should also seek medical care. In most cases, however, this condition will pass within a few weeks without medical attention or intervention.