Treatment of Nausea in Strep Throat with Amoxicillin Allergy
For nausea management in this patient, ondansetron (Zofran) 4-8 mg IV or PO is appropriate symptomatic treatment, while the underlying strep throat should be treated with an alternative antibiotic to amoxicillin. 1
Nausea Management
Ondansetron is an effective antiemetic for general nausea control and can be administered at doses of 4-8 mg intravenously or orally. 1 This 5-HT3 antagonist provides symptom-directed treatment without significant contraindications in this clinical scenario.
Alternative Antiemetic Options
- Metoclopramide 10 mg IV showed comparable efficacy to ondansetron in emergency department studies of nausea, with median VAS reductions of -30 mm versus -22 mm respectively (difference not statistically significant). 2
- Promethazine 12.5 mg IV also demonstrated similar nausea reduction (-29 mm VAS reduction) compared to ondansetron. 2
Antibiotic Selection for Penicillin-Allergic Patients
The severity of the amoxicillin allergy determines the appropriate antibiotic choice:
For Non-Severe Penicillin Allergy
First-generation cephalosporins are the preferred alternative when the patient does not have a history of anaphylaxis, angioedema, respiratory distress, or urticaria following penicillin or cephalosporin administration. 1, 3
- Cephalexin (Keflex) 500 mg PO twice daily for 10 days is strongly recommended. 1
- Cefadroxil 1 g PO once daily for 10 days is an acceptable alternative. 1
For Severe Penicillin Allergy
If the patient has a history of anaphylaxis, angioedema, respiratory distress, or urticaria to penicillins, avoid all cephalosporins due to cross-reactivity risk. 3
Recommended alternatives include:
- Clindamycin 300 mg PO three times daily for 10 days (strong recommendation, moderate evidence). 1
- Azithromycin 500 mg PO once daily for 5 days (strong recommendation, moderate evidence). 1
- Clarithromycin 250 mg PO twice daily for 10 days (strong recommendation, moderate evidence). 1
Important Caveat About Macrolides
Macrolide resistance in Group A Streptococcus varies geographically and temporally, so these agents should be used with awareness of local resistance patterns. 1 Studies show clarithromycin-resistant isolates have significantly lower eradication rates (14-19%) compared to susceptible isolates (74-83%). 4
Clinical Pearls
- Patients should complete 24 hours of antibiotic therapy before returning to school or work, as 36% of patients remain culture-positive the morning after initiating treatment. 5
- Adjunctive analgesics or antipyretics (acetaminophen or NSAIDs) should be recommended for moderate to severe throat pain or fever control. 1
- Adequate hydration is an important supportive measure during treatment. 1
- Avoid aspirin in children due to Reye's syndrome risk. 1