I don't LIKE it at all!! it IS however a known risk with a large enema.
It can also happen if you take an enema while Magnesium Citrate is still going to work.
Best preventative strategies
1) When you take a 4-qt enema, take a series of 2 or 3 quart soapsuds enemas FIRST, to get to a clear return. you will be surprised how much still comes out with that 4-qt enema.
2) Wait AT LEAST 30-45 minutes after the last enema fully expelled before taking the next one. Don't do anything physically strenuous during that time.
3)ALWAYS wait at least 8 hours,better 12+ hours between the last solid food, and the first 2-qt enema. NO ALCOHOL during that time!!
4) Wait at least 90 minutes after drinking any Magnesium Citrate before trying that 4-qt enema.
5) Mind the basics: always pee first, so there is as little pressure as possible on the lower abdomen that is not caused by the enema. Choose a position, either knee-chest or Simms BEFORE you start, get in that position, and STAY THERE until you can't, you HAVE TO head for the toilet. Make SURE the nozzle is pointed TOWARDS the navel during injection. Give yourself time to relax between insertion and injection.
6) Keep a clean dishpan or trashcan at arm's reach in case your body has it's own ideas about keeping things down.
7) If you DO choose to use Magnesium Citrate, DON'T GUZZLE!! Refrigerate it overnight, or ice it down. Get a stadium cup, fill it with water. SIP the magnesium Citrate, then a sip of water, count to 10 Repeat. When the magnesium Citrate bottle is empty, drink the rest of the water over the next 10 minutes. Your first couple of times, until you know how your body responds, you may want to do this kneeling in front of the toilet.
I hope this helps with the vomiting issue. Only promise: It WILL improve your odds of not vomiting.