That medication is also known as Stelazine, a name some on the board may recognize more. It is an older antipsychotic, sometimes prescribed for mental issues such as schizophrenia. It is not as often prescribed because the side effects can be more severe than some of the more recently developed medications that treat the same issues.

The side effects you mention that include shallow breathing are pretty significant- in triage, for example in an ER, breathing is basically the first thing attended to. Any sign of difficulty breathing or abnormality in breathing should be of concern. Accompanied with the other things you mention, I would be concerned.

I am not really intending to question your/her doctor, but it's possible they don't quite understand the severity of the side effects she is experiencing, or the message isn't entirely clear.

My suggestion is not to outright stop the medication, but to see a doctor as soon as possible if she is still experiencing these symptoms/side effects.

If not the doctor who prescribed the medication, than her general practitioner or an urgent care doctor if possible.

Breathing plus swelling plus rapid heart beat means that the body is responding to something. It is possible it is not the medication, specifically, but that doesn't mean these signs should necessarily be ignored, yes?

I hope she feels better soon.