Heat Induced Urticaria

Heat induced urticaria presents within five minutes after the skin has been exposed to heat above 109 degrees Fahrenheit. Typically, the exposed area burns, stings, turns red, and swells. Just as cold induced urticaria is caused by exposure to cold, heat induced urticaria is triggered by heat. It is a subcategory of cholinergic urticaria and occurs in both men and women; however, it seems to be more common in men than in women.

Individuals prone to this type of urticaria must avoid extreme temperatures. If the individual has developed the symptoms, try to cool down the affected area with an ice pack or cool compresses. However, if the symptoms do not go away, a doctor should be consulted.

Heat Urticaria

Heat urticaria is one of the most uncommon forms of urticaria. It is an extremely rare condition in which hives develop 2 to 5 minutes after contact with a warm stimulus or environments with very high temperatures. These hives do not last very long and mostly resolve within 1 hour after the outbreak. This specific condition is also known as localized heat urticaria, which completely distinguishes it from generalized heat urticaria or cholinergic urticaria.

The method with which doctors diagnose heat urticaria may seem strange. Warm water from a test tube is applied to the patient's forearm. If the patient is prone to heat urticaria, hives should develop within a few minutes.

The condition occurs when mast cells release histamines into the skin in response to extreme heat. Therefore, antihistamines may be helpful to treat this problem. In some cases, patients have been treated with desensitization methods, utilizing hot baths; however, this kind of therapy must be initiated under medical supervision.