<s>[INST] My son has small flat red patch that last a day or two then dissapears as quickly as it appears! No irritation -about half a centimetre in diameter. He suffers from exzema-but these look like a small bleed under the skin. He is nine years old. weighs average height and weight. Has been on steroid treatment for most of his life. Only other symptom he has is occasionally complaining of painful calves. [/INST] Hired patches are a part of allergy and is called urticaria. Here is the best way to control it is Avoidance of allergens. Most of the time patents or child Chat Doctor.  Here I would suggest you to get an allergen test done after consulting an allergist/immunologist. Avoiding the allergens detected in allergy test will help in decreasing the episodes. You may also try allergy controller like montelukast and cetirizine combination. Regards </s>