Welcome to Healthcare Magic You have Cholinergic urticaria or Chronic heat hives. It occurs whenever temperature of body increases, like during fever, stress, and going near heat source as well. You need to wear cool cotton clothes to avoid heating up of body. Avoid synthetic material clothes. Eat fresh fruits and green leafy vegetables. Drink enough water everyday. To abort an attack you can take over the counter antihistamines like Cetrizine which will offer relief. Nowadays there is specific anti-IgE therapy with drugs like Omalizumab which works to relieve symptoms and prevent further attacks. Consult your Dermatologist/Immunologist for proper advice in this regard.