Does my patient need an allergy evaluation for penicillin allergy?

Recommended approach to patients with reported penicillin allergy based on PEN-FAST risk stratification.

^aA drug challenge can be performed by a non-allergist or allergist under medical observation. Informed consent must be obtained from the patient.

^bFor a direct challenge in an adult patient, a single dose of 250 mg of amoxicillin followed by 60 to 120 minutes of observation is a common approach. Graded amoxicillin challenges are often performed by giving one-tenth of the full dose followed by the remaining dose with 30 to 60 minutes of observation between steps. In pediatric patients, amoxicillin challenges are performed using weight-based dosing. Drug challenge with the culprit penicillin could also be considered.

^cAny type of penicillin can be given without restriction. For those with reported allergy to penicillin only, any other beta-lactam can be utilized as indicated.

^dSkin testing and drug challenge are contraindicated in patients with a history of severe delayed reaction such as Stevens-Johnson syndrome/toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms, interstitial nephritis, serum sickness, or hemolytic anemia attributed to penicillin use.

^eSkin testing should be performed only by adequately trained providers.

PEN-FAST = PENicillin allergy reported; Five years or less since a reaction, or unknown interval; Anaphylaxis or angioedema, or Severe cutaneous reaction; Treatment was required for the allergy episode