Suicide, suicidal ideation, psychosis, aggression, anxiety, drug abuse/overdose, psychotic disorder, and hallucination have been reported in less than 1% of patients treated with peginterferon alfa-2a alone or in combination with
ribavirin tablets. Impairment of desire and the potential to affect sexual satisfaction have been reported with ribavirin tablets in combination with peginterferon alfa-2a in male patients."
Read more at http://www.drugs.com/sfx/ribavirin-side-effects.