Symptoms: Immediate pain at the site of the bite and red bumps that itch.
How to treat: Wash the bite with soap and water. Then apply ice for about 15 minutes at a time, several times a day. Or use an over-the-counter bite-relief product that contains ammonia, such as After Bite ($4 at drugstores), to reduce pain and itching, says Roxanne Connelly, an associate professor of entomology at the University of Florida, in Vero Beach. Avoid scratching so you don’t break the skin and invite infection.
Good to know: The bites of some flies, including horseflies and deer flies, can bleed. If the bleeding doesn’t stop on its own, see a doctor.