OBJECTIVE: The medical literature points out the adherence and ribavirin dose as important factors to achieve the best results in the CHC treatment. In Brazil, the government set local assisted administration centers (LAAC) to provide the drugs and administer the interferons (conventional and peguilated) to the patients in order to improve these factors. The objective of this study is to evaluate the adherence to the CHC treatment with peguinterferon and conventional interferon and the actual dose of ribavirin administered to the patients, in Brazil. METHODS: Thirty physicians in south, southwest and Midwest regions of Brazil performed a prospective cross sectional evaluation. They used a structured questionnaire with the specific questions. RESULTS: A total of 656 patients were evaluated during 2 months. The average age was 44 years and the mean body weight was 70.5 kg. According to the BMI, 50% of the patients are over-weight or obese. The adherence to treatment was calculated as the rate between the prescribed doses and doses actually taken. 79.7% of the patients was 100% adherent. Only 60.8% of the patients was 100% adherent to conventional interferon. 84.6% of the patients were 100% adherent to peginterferon alfa 2 a and 86.8% of the patients were 100% adherent to peginterferon alfa 2b. LAAC patients adherence (100%) is greater than the patients that apply the treatment (interferons) at home (84.8% vs. 71.1%). 93.4% of the Brazilian patients receive 1g per day or more of ribavirin. Given that the mean weight of the Brazilian patient is 70.5 kg the majority of the patients receive more than 10.6 mg/kg of ribavirin. CONCLUSIONS: The median weight of the Brazilian patients is 70.5 kg. More than 90% of the patients are receiving 1g per day or more of ribavirin. LAAC appear to directly affect the adherence to the treatment, improving it.