Brief Answer: Urticaria; give loratadine Detailed Answer: Hello XXXX, Welcome to the forum and thanks for posting your query. After reading the complete query with diligence I can make out that your daughter had an episode of “Urticaria” or commonly known as “Hives” To tell you Medically - Our blood contains multiple type cells including red blood cells and white blood cells. Specifically these white blood cells provide immunity to our body which are of further multiple types. Whenever anything in body is not suitable or offending to body then the number of white blood cells increases transiently. Particularly these cells which increase are eosinophils and basophils which are also known as mast cells. These cells contain granules which have a specific chemical known as histamine. So as soon as any offending factors come in contact there is bursting of the mast cells. There fore this histamine is released and we experience variable degree of itching and the kind of bumps which we can see in your daughter. The bumps can remain for a very transient period to upto multiple hours. It can remain for more than 12 hours too depending on the intensity of the offending factor but never more than 24 hours. Now the type of offending factor are innumerable including our food, environmental factors including temperature variation, heat, humidity, cold, dust and even simple of fragrances in air and multiple of other related things. In your daughter’s case as these are occurred on exposed region so most probably it may be related to environmental factors (as you rightly pointed out heat) or any contact allergen. For the treatment part - it is quite simple and treated with drugs which inhibits the histamine release also known as Antihistamines. If I were your daughter’s dermatologist then would have prescribed with loratadine (Claritin) which is most favored drugs for the treatment. I myself prefer Loratadine ( Alaspan or Lorfast) in my patients as it is very simple medicine without any side effects of sedation. In my patients I start with 1 tablets/day and can give for 1 week period. If there is no effect in 24 hours then can increase up to 2-3 times per day. In general urticaria may remain for short time in environmental factor induced problem. In most of the cases as our immune system and body get adjusted to that particular offending factor so it then self subsides. I hope these information will help you in dealing the condition better. If you have any further queries I will be glad to help you. With good health wishes, Dr Sanjay MD - Dermatology

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