Psychological side-effects of Interferon

Does anybody know about the possible side-effects of interferon
treatments after having a series of lymph nodes removed? My mother was

diagnosed with Clarks level 6 melanoma, and recently completed her
first month of daily IFN treatments, followed by a month of injections
3 times per week. Recently her behaviour changed dramatically and has
shown many different personality traits, such as talking excessively,
loudly, inappropriate comments, insomnia, excessive energy and general
mania. Doctors have diagnosed it as agitated depression, so I am
looking for more information or people who have any experience with
this.

Thanks in advance,

S.

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