Pertussis: Antibiotic Dosing

Medication

Dosing Recommendations

Special Considerations

   First-Line

Azithromycin¹

(oral, IV)

• <6 months: 10 mg/kg per day for 5 days
• > 6 months of age and children: 10 mg/kg (maximum: 500 mg) on day 1, followed by 5 mg/kg per day (maximum: 250 mg) on days 2-5
• Adolescents and adults: 500 mg on day 1, followed by 250 mg per day on days 2-5

• Preferred agent, including for infants < 1 month
• For infants < 1 month, particularly < 14 days old, counsel family to monitor for infantile hypertrophic pyloric stenosis (IHPS)
• Use with caution in patients with certain heart conditions (QT prolongation) and/or taking anti-arrhythmic medications, certain migraine medications and certain anti-psychotics
• Avoid for patients with know heart rhythm disorders or are taking multiple QT prolonging medications; defer to their specialist or PCP for prescribing of post-exposure prophylaxis

   Alternatives*

Trimethoprim-Sulfamethoxazole (TMP/SMX)²

(oral)

• < 2 months: Contraindicated
• > 2 months and children: 4 mg/kg/dose (dosed on TMP component) PO Q12H for 14 days
• Adolescents and adults: 160 mg/dose (dosed on TMP component) PO Q12H for 14 days

• Intolerance to macrolides or any component of the formulation
• Avoid if known G6PD deficiency, significant renal disease, concurrently taking dofetilide
• Significant drug interactions (via CYP2C9 and CYP34A inhibition)
• Not recommended for use in pregnant or breastfeeding women