Fungal infection is becoming an increasing problem due to rampant usage of antifungals. Please see a dermatologist as some extra medications are coprescribed many a times to treat. If needed a simple skin test can also be done. Till then use only OTC anti-allergic medications to control itching. Personal hygiene should be good. Wear loose fitting clothes Based on your description, it appears that you have dermographism. A ommon mistake is to take antihistamines as when and needed while it should be taken for a reasonably long time frame whether you develop dermographism or not. After a certain period,its advisable to wean the treatment