Interferon combined with ribavirin is widely used to decrease the burden of Hepatitis C virus (HCV), but some serious side effects might limit its usefulness. There has been recently a growing awareness about neuropsychiatric complications of many drug treatments. Anecdotal case reports of HCV treatment induced psychosis were published but there seems to be no consensus about the causative relation and no systematic reviews were done to the date.

To describe a paradigmatic case that was managed as an iatrogenic psychotic episode following interferon associated with ribavirin.

Call attention to problems that interfere with the recognition, diagnosis and management of drugs induced psychosis.

Bibliographic research was conducted through the PubMed in the Medline library and clinical information was obtained through medical records and clinical interviews with the patient.

A 50-year-old Brazilian woman, with a previous episode of postpartum depression, presented with paranoid psychosis six months after initiating HCV antiviral therapy. Psychotic symptoms consisted of persecutory delusions and auditory hallucinations and developed together with agitation and aggressive behavior. Psychiatric hospitalization was required and psychosis resolved with discontinuation of therapy and initiation of risperidone. Laboratory tests and brain images were of no help in the etiologic investigation.

There are many drugs known to possibly cause neuropsychiatric symptoms. It is the job of every physician to be aware of this hypothesis especially in cases with acute onset and atypical presentations.

The authors have not supplied their declaration of competing interest.