Prickly heat and allergies are two different diseases, each with many significant distinctions. First, prickly heat tends to occur when the temperature is high, the weather is hot, and the body's resistance is low, while allergies are likely to occur when the skin reacts to certain foods, weather conditions, or allergens, causing corresponding skin symptoms. The treatment for prickly heat primarily involves the use of cooling powders applied externally, while maintaining a cool environment and bathing frequently. Allergies, on the other hand, are mainly treated with oral antihistamines.