Treatments and drugs

By Mayo Clinic Staff

If you have an allergic reaction after taking an antibiotic in the penicillin family, you should:

  • Stop taking the medication and ask your doctor about another antibiotic
  • Avoid using penicillin in the future

Treatment for signs and symptoms you develop during an allergic reaction to penicillin depends on what kind of reaction you have.

  • Anaphylaxis is the most rare and serious allergic drug reaction. It can be life-threatening and requires an injection of epinephrine (adrenaline) and emergency care to maintain blood pressure and support breathing.
  • Rashes or hives may improve when treated with an antihistamine, such as diphenhydramine (Benadryl, others). More severe reactions may require treatment with oral or injected corticosteroids.
Dec. 15, 2011