There are lots of information available on how to treat heat rash in books and online resources. However when there was no books or internet was there then also people had learnt how to treat heat rash. Those techniques must have got developed over a period of time by experimentation and hit and trial method and by experimentation.Sometimes it might have given adverse effects and people would have learnt from the incidences. After learning them those techniques must have been propagated from one generation to the other generation by word of mouth about how to treat heat rash. Before discussing more about how to treat heat rashes lets look into how heat rashes appear and what are the symptoms and prognosis of heat rashes. Heat rash usually occurs in hot and humid climatic conditions when the sweating process is not proper and they get trapped in the layers of skin. These are also called prickly heat alternatively. The heat rash occurs as red spots in the skin. Usually to treat heat rash there are several home remedies.It can be treated at home, but at the same time there are some precautions which can be followed to ensure that heat rash doesn't occur. First of all one should come out of a hot condition to a cooler atmosphere of general  room  temperature or an air conditioned area. You should see there is proper air ventilation in the area which you are occupying. You can clean the area with mild soap and cool water. After cleaning the skin wipe it with a soft cotton towel or cloth. You should take care to not to irritate the skin by extra rubbing. Gentle rinsing is what needed to wipe the water out. You should apply calamine lotion gently to the affected heat rash to treat it. Alon with this one might consider to take an oat meal bath. Sometimes to treat heat rash you might be advised by a medical practitioner to take antihistamine medication to prevent itching sensation. One should avoid clothing which might cause irritation or too tight dresses which might prevent air passage to skin. Loose clothing are good to wear in such conditions. Wearing cotton clothing or polypropylene clothing specially designed for keeping sweat away from skin is beneficial. You should stay away from heat till the heat rash disappears. In case of worsening conditions you should consult a medical practitioner who can provide you with best advices. However most of the times it is easy to treat heat rash at home it self and does not require medical intervention.