How to Treat Heat Hives

Heat hives, or cholinergic urticaria, arise when a rise in body temperature and sweating prompts an itchy hive response. Episodes may follow exercise, hot water, warm weather, stress, or tightly layered clothing. The same person may have several triggers, so treatment is often built around the pattern rather than one suspected cause.

A clinician may examine the rash and ask how quickly it appears, how long individual spots last, and whether there is swelling beyond the skin. Other rashes can look similar, so persistent or unusual symptoms should be assessed.

Stop the activity that is making you warm, move to a cooler area, loosen clothing, and rinse with comfortably cool water. Use breathable fabrics and warm up gradually before exercise. Keep a trigger diary with the activity, heat exposure, foods, medicines, and symptoms. Avoid applying new fragranced products to an active rash.

If cooling and trigger changes are not enough, ask whether an oral antihistamine is appropriate, how to take it, and whether drowsiness or other effects matter for your routine. More information is available under [Antihistamine Treatment](/treatments/medical-dermatology/oral-antihistamine-therapy/).

Seek emergency help if hives occur with difficulty breathing, wheezing, swelling of the lips, tongue or throat, faintness, or a feeling that you may collapse. Book a review when episodes are frequent, severe, unexplained, or associated with painful skin, fever, or marks that do not fade like hives.

How can we confirm the diagnosis? Which triggers are most relevant in my pattern? Is an antihistamine suitable, and when should it be taken? Can I exercise safely, and what symptoms mean I should stop and seek help?