Can I have polyethylene glycol 2 days before breast augmentation?

Most over the counter laxatives should be safe but you should get your surgeons recommendations.  You don't want to have diarrhea and dehydration the morning of your surgery.

Because most patients use pain medication after surgery, the narcotics are known to cause constipation. This isn't a complication of surgery - it's an expected side effect of opiods (percocet, lortab, vicodin, etc). Aside from reducing the amount of pain medication you take, the other effective way to avoid constipation is to take (in this order, and move on to the next medication if constipation doesn't resolve): dulcolax, magnesium citrate, Fleet's Phosphasoda. That'll do the trick! Click on the web reference link below to find a plastic surgeon and pricing in your area.

Miralax (polyethylene glycol) is a safe way to address your constipation issues before and after surgery.  It is relatively gentle and has few side effects.  It will not cause bleeding problems or anesthesia problems.  Make sure to stay well hydrated which will help during surgery and will help also address the constipation.  Best of luck.