Algorithm to identify patients at low risk
for penicillin/beta-lactam allergy
Parents are unconvinced, but history indicates this patient is at no increased risk for a drug allergy compared with any other. To provide evidence to parents/guardians that the child is not allergic, provide a low risk, single test dose to oral amoxicillin.
Informed consent:
The handout above quotes a higher risk rate appropriate for low-medium risk challenges. Based on the history provided thus far, this patient has a >99% of tolerating amoxicillin ( a lower chance of having a reaction than quoted in this handout).
This handout quotes that following risks for an amoxicillin challenge:
1% have hives only
4% have a delayed (non dangerous) rash develop
Equipment in your community clinic you will need to manage this:
Epinephrine 0.01mg/kg, with a 25 gauge, 1 1/2 inch needle for administration into the lateral thigh if required
or
Epinephrine autoinjector (EpiPen) 0.15mg and 0.3mg
Contraindications:
Currently on antihistamines (they will mask symptoms)
Vomiting more than once in the last 24 hours
Concerning respiratory symptoms (wheeze, needing O2)
Critically ill
Current Rash
NPO
Protocol:
Amoxicillin 15mg/kg orally (max dose for challenge of 250mg). Use oral chewable amoxicillin of 125mg/tablet or 250mg/tablet to reduce cost to family/clinic. You can round up to dosing as high as 30mg/kg to facilitate use of a chewable tablet. Tablet may be crushed, and mixed in water to improve taste if the child is picky). Parenteral administration should be avoided for this test dose.
Observe for 30-60 minutes. Was the dose well tolerated?