Is there an allergy to sweat? The increase in body temperature can cause in some people what is known as ‘cholinergic urticaria’, manifesting as skin lesions, redness and itching. Dr. De la Roca, specialist in allergy at CreuBlanca, explains why it appears, how it is diagnosed and what are the keys to proper treatment.

What is a sweat allergy?

Sweat is the mechanism that our body has to self-regulate the increase in body temperature. In some people, the increase in body temperature and consequent sweating leads to itchy skin and even skin lesions. This picture is known as cholinergic urticaria.

What causes sweat allergy?

Although the exact underlying cause is not known, cholinergic urticaria is triggered by an increase in body temperature and not by sweat itself. The increase in temperature that occurs with intense physical exercise, emotional stress, hot baths and showers, even with the intake of spicy foods, are common factors that can cause cholinergic urticaria.

What symptoms does allergy to sweat produce?

Cholinergic urticaria causes symptoms that include the appearance of small red lesions (papules) 1-5 mm in diameter associated with itching. Skin lesions and itching can occur both on the trunk and on all the extremities and are usually a rapidly evolving picture. Any physical activity that leads to an increase in body temperature may be enough to trigger symptoms.

In adolescents and young adults it is common to observe the rapid appearance of lesions in the trunk and upper limbs after performing physical activity, even while doing it.

How is sweat allergy diagnosed?

The specialist performs a detailed clinical assessment of the patient’s symptoms and medical history, asking questions about the triggers for these symptoms and their duration, among other relevant factors. In addition, he may perform a physical examination of the skin and, if necessary, order additional tests. In some cases, your doctor may recommend allergy testing or blood work to rule out other possible allergies related to sweating triggers, such as certain foods or medications.

What is the treatment for sweat allergy?

Cholinergic urticaria does not have a specific treatment. Symptoms usually disappear spontaneously in less than 1 hour. This improvement is due to the self-regulation of body temperature. Contact with cold water can accelerate the disappearance of symptoms, especially in those people who present episodes of cholinergic urticaria with physical exercise or during hot showers. Oral antihistamines also help control symptoms. Its effect is not as immediate as cold showers, but in case of very annoying symptoms they can be used.

At the CreuBlanca Allergology Unit we approach all kinds of allergies from a comprehensive point of view, analyzing the immunological and environmental factors involved in their development. A multidisciplinary team of specialists made up of internists, allergists, dermatologists and nutritionists work together to offer you an accurate diagnosis and a personalized treatment plan, focused on relieving your symptoms and improving the prognosis of your allergy.