o study population pharmacokinetics in Benznidazole-treated adult patients with Chronic Chagas Disease to get information to optimize drug doses.

Inclusion Criteria:

• Adult patients with Chronic Chagas Disease diagnosed by 2 different and positive serological tests.
• Patients with Chronic Chagas Disease who are going to start treatment with Benznidazole.
• Any gender.
• All the participants must agree to participate in the study and must sign the informed consent.

Exclusion Criteria:

• Patients younger than 18.
• Patients with previous hypersensitivity to Benznidazole.
• Immunocompromised patients as AIDS, cancer, chemotherapy, longterm corticoids need, primary immunodeficiency, or any other.
• Hepatic dysfunction
• Renal dysfunction: serum creatinin higher than 3 mg/dl.
• Pregnancy or lactation.
• Low adhesion to treatment or check-up.
• Impossibility of follow-up.
• Severe adverse reaction to Benznidazole.
• Any other situation that could be risky for the patient.