What side effects would there be if someone healthy was given anti-psychotics?

A lot potentially: Drowsiness, jittery, muscle spasms, nausea, vomiting, "spacey" feeling, heart rhythm changes, dizziness. I'm assuming this is experimentation, not a doctor's prescription. You shouldn't take a prescription med without a doctor supervising. There are some non psychiatric uses for antipsychotic meds. In that case your doc will prescribe at a dose aimed at your symptoms.