Patients labeled as penicillin allergic, rarely have this confirmed and being labeled as "penicillin allergic" is associated with increased health care costs, adverse effects and antibiotic resistance. The investigators will recruit participants from primary care practices labeled as penicillin allergic and offer allergy testing. The aim of this study is to develop a community, outpatient program for evaluation of penicillin allergy.

Inclusion Criteria:

1. Labeled as having penicillin or amoxicillin allergy
2. Family history of penicillin allergy

Exclusion Criteria:

1. History of beta-lactam associated toxic epidermal necrolysis/Stevens Johnson syndrome to penicillin or amoxicillin
2. History of Drug induced Eosinophilia with Systemic Symptoms (DRESS)
3. History of drug induced: autoimmune hepatitis/interstitial nephritis, or hemolytic anemia
4. Poorly controlled asthma or heart disease
5. Currently pregnant
6. Unable to discontinue certain medications that may interfere with testing including (antihistamines, steroids, beta-blockers, tricyclic antidepressants, omalizumab)

Adults ages 18 and older from the general population.