Treatment of Untreated Pertussis in a 10-Year-Old

First-Line Treatment Options

The Centers for Disease Control and Prevention recommends azithromycin as the preferred macrolide antibiotic for treating pertussis in children, due to its better tolerability and shorter treatment duration compared to erythromycin, with a dosage of 10 mg/kg (maximum 500 mg) on day 1, then 5 mg/kg (maximum 250 mg) daily for 4 days 1, 2
The American Academy of Pediatrics recommends clarithromycin as an alternative macrolide antibiotic, with a dosage of 7.5 mg/kg (maximum 500 mg) twice daily for 7 days, due to its better tolerability than erythromycin 2

Antibiotics are most effective when started during the catarrhal stage (first 1-2 weeks) of pertussis, and can reduce infectiousness and prevent transmission, with approximately 80-90% of patients spontaneously clearing B. pertussis from the nasopharynx within 3-4 weeks from onset of cough 1, 4, 5
The World Health Organization notes that even when started during the paroxysmal stage, antibiotics can eradicate B. pertussis from the nasopharynx and reduce severity and duration of symptoms if started early 1, 2, 4

The Centers for Disease Control and Prevention recommends post-exposure prophylaxis (PEP) with the same antibiotics used for treatment, to be administered within 21 days of exposure, and verification and update of vaccination status of all contacts if needed 3, 6

Potential complications to monitor include weight loss, sleep disturbance, pressure-related effects from severe coughing, secondary bacterial infections, and neurological complications, with a strength of evidence rated as high for these complications 1, 4