Thank you for your contact to health care magic. I read and understand your concern. I am Dr J.D Mangukiya answering your concern. The horsefly is known under many different names in different countries, including deer flies, clags, gadflies or breeze flies. This can be dangerous because the horsefly can transmit parasites or diseases amongst its victims. Horsefly bites may take longer time to heal than other insect bites which generally take two to three days Many cultures have developed remedies to assist with the pain of a horsefly bite. Icing the wound will help reduce swelling and dull the pain associated with a bite. You can also apply aloe vera, vinegar, Epsom salt, raw onion, mud, honey, a paste made from baking soda or vinegar to the bite to help reduce swelling and discomfort. Once you have applied a topical agent to provide relief, cover the area with a loose bandage to protect the wound and to help keep the remedy in place. You have already taken Benadryl for swelling and itching.so next you should try 1% hydrocortisone cream to the area to help eliminate these symptoms. I will be happy to answer your further concern. Thank you, Dr J.D. Mangukiya Infectious diseases specialist, TEAM HCM.