Magnesium citrate
constipation
"Magnesium Citrate is the nuclear option. If this stuff doesn't work, you ought to think about going to E.R.  Only use this when you can stay home for about 12 hours. I drink 1 ten ounce bottle and about 16 ounces of water. If it doesn't kick in after four hours I'll drink another half bottle and drink more water. The more water you drink, the better and sooner it will work. Plan on multiple trips to the toilet and when you're sure there couldn't possibly be any more, stay put for another hour. Also, and this is important, once you drink it, don't trust a fart!!!"