Key takeaways
Magnesium citrate (Citroma) and polyethylene glycol 3350 (MiraLAX, GaviLAX, Clearlax) are both over-the-counter medications used to treat occasional constipation. However, they belong to different medication classes. Magnesium citrate is a saline laxative that works by helping your intestines hold onto water, while polyethylene glycol 3350 is an osmotic laxative that brings more fluid into your colon to soften your stool. Magnesium citrate typically produces a bowel movement within 30 minutes to 6 hours, whereas polyethylene glycol 3350 usually takes 1 to 3 days to work. Magnesium citrate is available in liquid form and is often taken in a single dose or divided doses, while polyethylene glycol 3350 comes as a powder that you mix with a beverage and take once a day. Magnesium citrate should be avoided if you have kidney problems, while polyethylene glycol 3350 can be used with caution under a provider's guidance. Common side effects of magnesium citrate include nausea and stomach pain, while polyethylene glycol 3350 may cause nausea, bloating, and gas. Both medications can cause diarrhea if taken in excess.
