RESUMO
BACKGROUND: Tongue hyperpigmentation is a rare side effect in patients with hepatitis C virus infection who are receiving peginterferon alfa and ribavirin combination therapy. Tongue hyperpigmentation usually occurs after the patient has undergone several months of treatment, and it resolves after the patient discontinues therapy. CASE DESCRIPTION: A 66-year-old dark-skinned woman with hepatitis C virus infection was referred to the Oral Diseases Treatment Center of São Leopoldo Mandic Dental School, Campinas, Brazil, for evaluation of tongue pigmentation after receiving peginterferon alfa and ribavirin combination therapy for 32 weeks. A physical examination showed dark brown, asymptomatic pigmentation in the dorsum of the tongue. Six months after the patient discontinued therapy, the authors observed a marked reduction in the pigmentation's intensity. CASE IMPLICATIONS: Dentists should be aware that hyperpigmentation of the tongue can result from peginterferon alfa and ribavirin combination therapy. A biopsy should be performed if no firm diagnosis can be obtained from clinical findings and the patient's medical history.