What is the treatment for pertussis?

Treatment of Pertussis

Azithromycin is the preferred first-line treatment for pertussis across all age groups due to its effectiveness, better tolerability, and convenient dosing regimen compared to other macrolides. 1

First-Line Treatment by Age Group

Infants < 1 Month

• Azithromycin is the only recommended macrolide for infants under 1 month of age 2, 1
• Erythromycin and clarithromycin are not recommended for this age group due to risk of infantile hypertrophic pyloric stenosis 2, 1

Infants 1-5 Months

• Azithromycin and clarithromycin are recommended as first-line agents 1
• Dosing for azithromycin: 10 mg/kg once daily for 5 days 1
• Dosing for clarithromycin: 7.5 mg/kg twice daily for 7 days 3

Children ≥ 6 Months and Adults

• Azithromycin: 10 mg/kg (maximum 500 mg) on day 1, followed by 5 mg/kg (maximum 250 mg) daily for days 2-5 1
• For adults: 500 mg on day 1, followed by 250 mg daily for days 2-5 1
• Clarithromycin: 7.5 mg/kg (maximum 500 mg) twice daily for 7 days 3
• Erythromycin: 40-50 mg/kg/day in 4 divided doses for 14 days (less preferred due to side effects) 2, 4

Alternative Treatment Options

• For patients aged >2 months with macrolide contraindications, trimethoprim-sulfamethoxazole (TMP-SMZ) is recommended 2, 1
• TMP-SMZ should not be used in infants <2 months due to risk of kernicterus 2

Treatment Timing and Effectiveness

• Antibiotics are most effective when started during the catarrhal stage (first 1-2 weeks) 3, 5
• Early treatment can reduce duration and severity of symptoms and decrease the period of communicability 1, 6
• Even when started during the paroxysmal stage, antibiotics can eradicate B. pertussis from the nasopharynx 3
• Note that antibiotics primarily prevent transmission rather than shortening disease course once cough is established 6

Post-Exposure Prophylaxis (PEP)

• The same antimicrobial agents and dosing regimens used for treatment are recommended for PEP 2, 1, 7
• PEP should be administered within 21 days of exposure to be effective 7
• PEP is strongly recommended for:
  • All household contacts 7
  • Close contacts of pertussis cases, especially in exposure settings with infants <12 months or pregnant women in third trimester 2, 7
  • Healthcare workers with known pertussis exposure 7

Important Considerations and Precautions

• Macrolides are contraindicated in patients with history of hypersensitivity to any macrolide agent 1
• Azithromycin should not be taken with aluminum- or magnesium-containing antacids as they reduce absorption 1
• Erythromycin and clarithromycin (but not azithromycin) inhibit the cytochrome P450 enzyme system and can interact with other drugs 2
• Pertussis is highly infectious with a secondary attack rate exceeding 80% among susceptible persons 7
• Patients with pertussis are most infectious during the catarrhal stage and the first 3 weeks after cough onset 7

Monitoring for Complications

• For infants: monitor for apnea, pneumonia, seizures, or death 5
• For all patients: monitor for weight loss, sleep disturbance, pressure-related effects from severe coughing, and secondary bacterial infections 3
• For adolescents and adults: complications are typically related to chronic cough 5

Preventive Measures

• Vaccination remains the most important preventive strategy 7
• Current recommendations include DTaP vaccine for children and Tdap booster for adolescents and adults 5, 6
• Pregnant women should receive Tdap between 27-36 weeks' gestation with each pregnancy to convey immunity to newborns 6