Allergies To Penicillins
Description General and Supportive Measures Medicine Treatment Referral ICD-10 code: Z88.0 DESCRIPTION Patients may present with immediate (e.g. anaphylaxis, bronchospasm, angioedema) or delayed reactions (most commonly maculopapular rash without systemic involvement; rarely SJS/TEN or other systemic reactions). GENERAL AND SUPPORTIVE MEASURES Stop penicillin. MEDIC
General and Supportive Measures
ICD-10 code: Z88.0
DESCRIPTION
Patients may present with immediate (e.g. anaphylaxis, bronchospasm, angioedema) or delayed reactions (most commonly maculopapular rash without systemic involvement; rarely SJS/TEN or other systemic reactions).
GENERAL AND SUPPORTIVE MEASURES
Stop penicillin.
MEDICINE TREATMENT
If an antibiotic is still required, treat with a suitable alternative antibiotic class according to the condition.
Milder infections
E.g. upper respiratory tract infections:
- Azithromycin, oral, 10 mg/kg/day for 3 days.
OR
E.g. impetigo, mild cellulitis:
- Clindamycin, oral, 6 mg/kg/dose 6 hourly for 3 days.
Severe infections e.g. osteomyelitis, pneumonia:
- Third generation cephalosporin, provided there is no history of immediate hypersensitivity (see below, cross-reactivity of other β-lactams).
Alternative antibiotics for gram-positive infections:
- Clindamycin, oral, 6 mg/kg/dose 6 hourly.
OR
- Vancomycin, IV, 15 mg/kg 8 hourly.
Urinary tract infection
- Neonates: Ciprofloxacin, oral, 6 mg/kg/dose 12 hourly.
- Infants: Ciprofloxacin, oral, 6 mg/kg/dose 8 hourly.
- > 1 year of age: Ciprofloxacin, oral, 10 mg/kg/dose 12 hourly.
Prophylaxis in rheumatic heart disease or post splenectomy, consider:
- Macrolide, e.g.
- < 11 years: Azithromycin, oral, 10 mg/kg/day, 3 times weekly.
- ≥ 11 years: Azithromycin, oral 250 mg daily.
Cross-reactivity of other β-lactams in patients with penicillin allergy
The risk of cross-reactivity to cephalosporins in penicillin allergic patients is low. Consequently, only avoid oral cephalosporins in patients with a history of anaphylaxis to penicillin.
In hospitalised patients, and in those with mild reactions such as rash to aminopenicillin, cephalosporins should not be avoided if indicated for infection. If concerned, discuss with expert and/or consider a test dose.
Risk of cross-reactivity is very low with carbapenems, and these agents can be used without allergy assessment in penicillin allergic patients.
| If no alternative antibiotic is available, consider desensitisation after consultation with a specialist. Desensitisation to be done by a specialist, in a tertiary facility |
REFERRAL
- In cases where desensitisation is considered.
- Consult a specialist for alternative antibiotics in all patients with severe, immediate reactions.
Standard Treatment Guidelines and Essential Medicines List for South Africa, Hospital Level, Paediatrics, 2023 Edition
Chapter 25: Drug Allergies, 24.4 Specific Allergies, 24.4.1 Allergies To Penicillins