Pollen counts are updated daily from February 15 to November 15.
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Many people who think they are penicillin allergic are not. They avoid this class of antibiotics known as beta lactams which are inexpensive, safe and recommended as a first choice drug for many diagnoses. It is estimated that 95% of these patients are not truly allergic but may have had an initial reaction which was falsely labeled as allergy or their allergy has waned with time. Penicillin testing can help clarify if you need to avoid this common class of antibiotics.
At your appointment our allergist will carefully review your history focusing on what happened after you were exposed to penicillin. The more details you have about these reactions the better. If appropriate they will order in office testing. There are two tests for diagnosis and you may receive one or both. Standard skin testing involves pricking or injecting skin with increasingly larger doses of penicillin. Allergist are looking for skin changes such as reddening or swelling at the test site. Blood testing, although less accurate, is sometimes used as well. If you pass skin testing with no sign of allergy you will likely be offered an in office oral challenge.
With the graded challenge, your allergist will give you penicillin to take. You will take five dosages in all. You receive the smallest dosage first, and your allergist watch your reactions. If you don’t react, you receive another dosage, and so on and so forth until you take all five dosages. By taking all five dosages of the medication without a reaction, your allergist can say for certain you don’t have a penicillin allergy anymore.
The best time to do testing is when you are well and not in need of an antibiotic. The goal is to be able to correct misidentified allergies to allow a wider selection of antibiotics when you do need them. The more options available the better since the overuse of a narrow selection of antibiotics can increase the possibility of antibiotic resistant organisms.
You should consider a penicillin allergy test if you were allergic to the medication in childhood and you’re curious if you outgrew your allergies. If you experience symptoms like angioedema (a type of swelling of the extremities and face) and hives after a dose of penicillin, you should also take the test.
As with all skin testing, antihistamines in all forms should be avoided 5 days prior to testing. You will receive instructions when you make your appointment on which medications need to be discontinued. Penicillin allergy tests are generally short. Barring any reactions, you can go back to work or school the same day. You should let your allergist know if you experience any symptoms, including stuffy nose (rhinitis), after the appointment.