ROCHESTER, N.Y. (WROC) — If you are one of the 10% of U.S. patients who have reported an allergic reaction to Penicillin as a kid, or even as an adult, you may not be allergic anymore. New research shows that up to 95% of people labeled as allergic to penicillin on their electronic medical records can safely take the medication after testing. "We know that penicillins are good medications to be able to use in general," said Jessica Stern, associate professor of allergy and immunology with URMC, "and when we avoid those, we're putting our patients — if they don't need to be avoided — at higher risk." Stern says there are usually two possible reasons people mistakenly think they're allergic to penicillin. They were either misdiagnosed during childhood when they actually experienced an intolerance, or they outgrew the allergy. "What often happens is, that label will be placed in childhood and never revisited," said Stern. "But it should always be revisited. Likewise, as adults, if we have that label, we should talk about it with our healthcare providers." Stern says about 50% of patients allergic to penicillin lose their sensitivity after five years and up to 85% lose their sensitivity after 10 years. That's important to note because, Stern says, if you no longer need the designation, the alternative — broad spectrum antibiotics — are associated with some risk. "We know that if you're hospitalized and you have 'penicillin allergy' listed in your medical record, you're at risk of higher healthcare cost and increased risk of hospital-acquired infections." Stern's final piece of advice? If you've reported being allergic because your family is — you can probably remove the designation since, most of the time, a penicillin allergy isn't hereditary.