By: Dr. Dan Hunt, M.D. CCFP
About one out of every ten people reading this article will have at some point in their lives been labelled as allergic to penicillin. However, in scientific studies in which people thought to be allergic to penicillin undergo thorough allergy testing, 90% of those tested can safely use penicillin type medications!
Why might this be? When a person receives penicillin for an illness they may develop symptoms that are attributed to allergy, such as: rash, itching, stomach upset, diarrhea, etc. These symptoms are not necessarily an allergy; they can also be caused by the underlying illness or are simply side effects of the medication. Other people may have had a true allergic reaction in the past, but with the passage of time lose their sensitivity to penicillin. By 5 years 50% of penicillin-allergic people are able to tolerate penicillin, and by 10 years 80% are able to use it.
Why does it matter? Penicillin type antibiotics are some of the safest and most effective antibiotics we have. Since its discovery in 1928 penicillin and related drugs have helped millions of people with diseases ranging from strep throat, to meningitis, to syphilis. Despite increasing rates of antibiotic resistance, penicillin type antibiotics remain the best treatment for many common and life threatening infections. Other antibiotics may be either less effective, have more side effects, or both. If a person who is labelled as penicillin allergic gets an infection requiring antibiotics, they may need to use an inferior antibiotic because at that point it’s too late to have allergy testing done to see if penicillin is safe. Even though we know that most people who have had a reaction in the past can safely take a penicillin antibiotic, it’s too dangerous to give it without allergy testing first.
What can you do about this? If you have been avoiding penicillin type antibiotics due to a reaction to penicillin or a related antibiotic (amoxicillin, ampicillin, cloxacillin, piperacillin) in the past you may benefit from a referral to an allergist for testing. This can be arranged through your family doctor. By getting tested you ensure that the next time you get a bacterial infection your doctor will be able to prescribe the best possible antibiotic for you.
For more information check out the American Academy of Allergy, Asthma and Immunology: www.aaaai.org