Nogle mennesker bliver deprimerede, når de anvender IntronA alene eller i kombinationsbehandling med ribavirin, og i nogle tilfælde fik mennesker tanker om at true andre mennesker på livet, selvmordstanker eller aggressiv opførsel (sommetider rettet mod andre).
 422 Some people get depressed when taking IntronA alone or in combination treatment with ribavirin, and in some cases people had thoughts about threatening the life of others, suicidal thoughts or aggressive behaviour (sometimes directed against others).