Introduction When co-administered with interferon and ribavirin, the prescription drug telaprevir significantly improves treatment response in patients with chronic hepatitis C virus (HCV) infection. Its use, however, also increases the likelihood of adverse effects that may lead to discontinuation of treatment. Cutaneous adverse effects are particularly common. Objective To determine the frequency and clinical characteristics of drug eruptions induced by telaprevir in patients receiving HCV treatment and to analyze the clinical course of lesions and response to treatment. Material and methods We performed a prospective observational study of all patients who started a treatment regimen that included telaprevir between May 2012 and July 2013. We recorded the demographic characteristics of the patients who developed telaprevir-induced eruptions, and analyzed the clinical characteristics of the lesions and their clinical course following the application of guideline-based treatment recommendations. Results Twenty (46%) of the 43 patients who received triple therapy with interferon, ribavirin, and telaprevir during the study period developed drug reactions attributable to telaprevir. The reaction was classified as mild or moderate (grades 1 or 2) in 90% of cases and consisted of an exanthem with erythematous-edematous scaling plaques and papules. The rash worsened, mainly by spreading, in about one-third of cases. The skin lesions led to discontinuation of treatment in 2 patients (4.6%). Sustained viral response was achieved in 34 patients (79%). Conclusions Telaprevir-induced eruptions are common and often progress, but they rarely require patients to discontinue treatment.