Antiparasitic Treatment

Antiparasitic treatment is indicated for all cases of acute or reactivated Chagas disease and for chronic T. cruzi infection in children up to age 18. Congenital infections are considered acute disease. Treatment is strongly recommended for adults up to 50 years old with chronic infection who do not already have advanced cardiomyopathy. For adults older than 50 years with chronic T. cruzi infection, the decision to treat with antiparasitic drugs should be individualized, weighing the potential benefits and risks for the patient. Physicians should consider factors such as the patient’s age, clinical status, preference, and overall health.

The two drugs used to treat infection with T. cruzi are nifurtimox and benznidazole. Benznidazole is approved by FDA for use in children 2–12 years of age and is available from www.benznidazoletablets.comexternal icon. Nifurtimox is not currently FDA approved but is available under investigational protocols from CDC. Side effects are fairly common with both drugs and tend to be more frequent and more severe with increasing age.

Common side effects of benznidazole treatment include the following:

  • Allergic dermatitis
  • Peripheral neuropathy
  • Anorexia and weight loss
  • Insomnia

The most common side effects of nifurtimox include the following:

  • Anorexia and weight loss
  • Polyneuropathy
  • Nausea
  • Vomiting
  • Headache
  • Dizziness or vertigo

Contraindications for treatment include severe hepatic and/or renal disease. As safety for infants exposed through breastfeeding has not been documented, withholding treatment while breastfeeding is also recommended. The following table outlines recommended dosage regimens by age group:

Drug Age group Dosage and duration
Benznidazole 2–12 years of age * 5–8 mg/kg per day orally in 2 divided doses for 60 days


≤ 10 years 15–20 mg/kg per day orally in 3 or 4 divided doses for 90 days
11–16 years 12.5–15 mg/kg per day orally in 3 or 4 divided doses for 90 days
17 years or older 8–10 mg/kg per day orally in 3 or 4 divided doses for 90 days

Questions regarding treatment should be directed to CDC’s Parasitic Diseases Inquiries (404-718-4745; e-mail

For emergencies (for example, acute Chagas disease with severe manifestations, Chagas disease in a newborn, or Chagas disease in an immunocompromised person) outside of regular business hours, call the CDC Emergency Operations Center (770-488-7100) and ask for the person on call for Parasitic Diseases.

* Benznidazole is FDA-approved for the treatment of Chagas disease (American trypanosomiasis) caused by Trypanosoma cruzi in pediatric patients 2–12 years of age. Use of benznidazole to treat a patient outside of the FDA-approved age range of 2–12 years is based on clinical diagnosis and decision by a treating physician under practice of medicine.

Guidance for Evaluation and Treatment

For more detailed information on evaluation and treatment, the following link provides free access to a review article:
Evaluation and Treatment of Chagas Disease in the United States: A Systematic Review (JAMA 2007: 298:2171-81)*external icon


Page last reviewed: October 9, 2019