An extremely rare case of delusional parasitosis in a chronic hepatitis C patient during pegylated interferon alpha-2b and ribavirin treatment

World J Gastroenterol. 2007 Apr 28;13(16):2379-80. doi: 10.3748/wjg.v13.i16.2379.


During treatment of chronic hepatitis C patients with interferon and ribavirin, a lot of side effects are described. Twenty-three percent to 44% of patients develop depression. A minority of patients evolve to psychosis. To the best of our knowledge, no cases of psychogenic parasitosis occurring during interferon therapy have been described in the literature. We present a 49-year-old woman who developed a delusional parasitosis during treatment with pegylated interferon alpha-2b weekly and ribavirin. She complained of seeing parasites and the larvae of fleas in her stools. This could not be confirmed by any technical examination. All the complaints disappeared after stopping pegylated interferon alpha-2b and reappeared after restarting it. She had a complete sustained viral response.

Publication types

  • Case Reports

MeSH terms

  • Antiviral Agents / adverse effects*
  • Antiviral Agents / therapeutic use
  • Female
  • Hepatitis C, Chronic / drug therapy
  • Humans
  • Interferon alpha-2
  • Interferon-alpha / adverse effects*
  • Interferon-alpha / therapeutic use
  • Middle Aged
  • Parasitic Diseases / psychology*
  • Recombinant Proteins
  • Ribavirin / adverse effects*
  • Ribavirin / therapeutic use
  • Schizophrenia, Paranoid / chemically induced*
  • Schizophrenia, Paranoid / diagnosis
  • Treatment Outcome


  • Antiviral Agents
  • Interferon alpha-2
  • Interferon-alpha
  • Recombinant Proteins
  • Ribavirin