Treatment

Timing

Early treatment of pertussis is very important. The earlier a person, especially an infant, starts treatment the better. If a patient starts treatment for pertussis early in the course of illness, during the first 1 to 2 weeks before coughing paroxysms occur, symptoms may be lessened. Clinicians should strongly consider treating prior to test results if clinical history is strongly suggestive or patient is at risk for severe or complicated disease (e.g., infants). If a clinician diagnoses the patient late, antibiotics will not alter the course of the illness and, even without antibiotics, the patient should no longer be spreading pertussis.

Persons with pertussis are infectious from the beginning of the catarrhal stage (runny nose, sneezing, low-grade fever, symptoms of the common cold) through the third week after the onset of paroxysms (multiple, rapid coughs) or until 5 days after the start of effective antimicrobial treatment.

A reasonable guideline is to treat persons older than 1 year of age within 3 weeks of cough onset and infants younger than 1 year of age and pregnant women (especially near term) within 6 weeks of cough onset.

Administer a course of antibiotics to close contacts within 3 weeks of exposure, especially in high-risk settings. Use the same doses as in the treatment schedule.

Antimicrobial Choice

The recommended antimicrobial agents for treatment or chemoprophylaxis of pertussis are azithromycin*, clarithromycin, and erythromycin. Clinicians can also use Trimethoprim-sulfamethoxasole. Clinicians should choose the antimicrobial after consideration of the:

• Potential for adverse events and drug interactions
• Tolerability
• Ease of adherence to the regimen prescribed
• Cost

Infants

Macrolides erythromycin, clarithromycin, and azithromycin are preferred for the treatment of pertussis in persons 1 month of age and older. For infants younger than 1 month of age, azithromycin is preferred for post exposure prophylaxis and treatment because azithromycin has not been associated with infantile hypertrophic pyloric stenosis (IHPS), whereas erythromycin has. For infants younger than 1 month of age, the risk of developing severe pertussis and life-threatening complications outweighs the potential risk of IHPS that has been associated with macrolide use. Clinicians should monitor infants younger than 1 month of age who receive a macrolide for the development of IHPS and for other serious adverse events. For persons 2 months of age and older, an alternative to macrolides is trimethoprim-sulfamethoxazole.

View photos of an infant getting treatment for pertussis in the hospital.

Footnote

On March 12, 2013, the Food and Drug Administration (FDA) issued a warning that azithromycin can cause abnormal changes in the electrical activity of the heart that may lead to a potentially fatal irregular heart rhythm in some patients. Azithromycin remains one of the recommended drugs for treatment and chemoprophylaxis of pertussis, but consider using an alternative drug in those who have known cardiovascular disease, including:

• Patients with known prolongation of the QT interval, a history of torsades de pointes, congenital long QT syndrome, bradyarrhythmias, or uncompensated heart failure
• Patients on drugs known to prolong the QT interval
• Patients with ongoing proarrhythmic conditions such as uncorrected hypokalemia or hypomagnesemia, clinically significant bradycardia, and in patients receiving Class IA (quinidine, procainamide) or Class III (dofetilide, amiodarone, sotalol) antiarrhythmic agents.

Elderly patients and patients with cardiac disease may be more susceptible to the effects of arrhythmogenic drugs on the QT interval.