In that case you need to learn to find this stuff on google.
You can find answers to any questions like that in short order.
http://www.medicinenet.com/rash/article.htm
http://www.emedicinehealth.com/insect_bites/article_em.htm
and hundreds of other sites. Find the best matches and search those.
When you find what fits exactly, search for treatment.
It’s fast and easy to find diagnosis and treatment for such things.