Objective: To report a case of recurrent unilateral presumed ocular toxocariasis after treatment of hepatitis C.Design: Case study.Methods: Clinical findings, ultrasonography, computed tomography, and serological tests were performed. Once diagnosis was made, effective treatment was administered.Results: A 46-year-old woman with a long history of decreased unilateral visual acuity presented with anterior uveitis after the use of interferon alpha and ribavirin for treatment of hepatitis C. A biomicroscopic examination revealed active anterior uveitis, with ultrasonography and computed tomography demonstrating a central granuloma due to partially calcified toxocariasis. After treatment with corticosteroids and cycloplegics, the symptoms were alleviated.Conclusion: immunostimulation could cause a relapse of the inflammatory reaction found in uveitis due to toxocariasis.