I am currently on a low dose antipsychotic. I plan on committing suicide in about 60 days. Should I stop taking my antipsychotic now so I don't run into issues with the primperan?
Because both metoclopramide and most, if not all, antipsychotics (both typical and atypical) are dopamine antagonists (also called dopamine blockers), there is major interaction between them, that can cause extrapyramidal symptoms (EPS). Therefore, you should most definitely interrupt your antipsychotic treatment a few days or so before starting the metoclopramide regimen. By the way, I am also on a low-dose antipsychotic (risperidone) and will do the same when the time comes.
Also, I am confused about what the best dosage to take in 48 hour regime is - 10, 15, 20? I'm really worried that I'll end up with weird symptoms and that it will interfere with my plan
The best regimen is the one that works for you, considering how prone to induce vomiting your method is and how prone to EPS (the "weird symptoms" that could appear) your body is. According to
the "Suicide" Wikibooks open book, you are at higher risk of EPS if you've already had EPS in the past, you have been on antipsychotics for a long time, you are under 30 y/o or you are a woman over 50 y/o. You cannot completely eliminate the risk, you have to try the regimen and see if you are able to complete it. If the symptoms are present to such a degree that they interfere with your plan, you have to stop the attempt and possibly switch to domperidone, which is a milder antidopaminergic antiemetic that poses virtually no risk of EPS.
