Penicillin is miraculous.  It was discovered in 1928 by Alexander Fleming (founding the modern era of antibiotic medicine) and is still the most common antibiotic prescribed in my jails.  The dentist and I use Penicillin VK as our preferred initial agent for dental infections.  I prescribe PCN VK, as well, for strep throats.  I use amoxicillin occasionally for sinus infections and UTIs and even amoxicillin/clavulanate (Augmentin) occasionally. 

Because penicillin is so useful (and inexpensive), I hate to hear the words “I’m allergic to penicillin.” If a patient with a dental infection can’t take penicillin, for example, the dentist commonly prescribes clindamycin, which is expensive, a pain to administer three times a day and has potentially bad side effects.  I have seen more than one patient who developed C. difficile after getting a broad-spectrum antibiotic because of a reported penicillin allergy–probably unnecessarily!

This problem is pretty common since about 10% of the adult population will report a penicillin allergy.  However, research has shown that, when tested, more than 90-95% of patients who state that they have a penicillin allergy really do not. These patients can be harmed by giving them an inferior antibiotic more likely to cause them harm than plain old penicillin.

The test most commonly used to gauge true allergic status is Penicillin Skin Testing (PST). No jail or prison that I know of does skin prick tests.  We also don’t refer patients reporting penicillin allergy to an allergist for testing.  We just groan and prescribe an inferior antibiotic. 

However, this could potentially change based on research published this year on the safety and efficacy of “Direct Challenge” penicillin allergy testing.  Direct challenge means giving a low-risk (this is important) patient an oral dose of whatever penicillin you want to prescribe and observing them for an hour for an allergic reaction. This has been done in studies and has been reported to be safe and effective.