From the Research
The first-line intravenous antibiotics for acute tonsillitis in Australia typically include benzylpenicillin (penicillin G) at a dose of 1.2g IV every 6 hours for adults, as recommended by recent guidelines and studies 1. For children, the dosage is typically 30mg/kg up to 1.2g every 6 hours. This treatment is usually continued until clinical improvement is observed, typically 24-48 hours, after which patients can be switched to oral antibiotics to complete a total 10-day course. Some key points to consider when treating acute tonsillitis include:
- For patients with penicillin allergy (non-immediate), cefazolin 2g IV every 8 hours (adults) or 25mg/kg up to 2g every 8 hours (children) is recommended.
- In cases of immediate penicillin hypersensitivity, clindamycin 600mg IV every 8 hours (adults) or 10mg/kg up to 600mg every 8 hours (children) is the alternative.
- IV antibiotics are generally reserved for severe tonsillitis cases with inability to swallow, systemic toxicity, or complications.
- Penicillin remains the first choice because Group A Streptococcus, the most common bacterial cause of tonsillitis, maintains excellent susceptibility to penicillin, which has a narrow spectrum of activity that minimizes disruption to normal flora and reduces antimicrobial resistance risk, as supported by a recent systematic review and clinical practice recommendations 1.
The most recent and highest quality study, a systematic review and clinical practice recommendations published in 2023 1, provides the basis for these recommendations, prioritizing morbidity, mortality, and quality of life as the outcome.