Effects - Heroin while prescribed to medication?

[classyfashh]

Swim just got prescribed to Anti-Psychotics and Anti-depressants. She takes 1 pill in the morning and 1 at night. The Anti-Psychotic is supposed to sedate you a bit but not too much. They aren't in high doses. Swim was wondering if she could still shoot up Heroin while being on this and if so, has anyone heard stories of people dying from mixing these?
The medication names are; Zoloft and Risperdal.

Please, anyone help, swim's a bit worried and hesitant to doing this but she's highly addicted and stopping is a definite no. She just doesn't understand why her doctors' in rehab would prescribe her to these medications if they know she does dope and relapses very easily.