Ann,
Yes, the mag citrate is probably the stuff you are thinking of.
My doctor's instructions said it had to be the lemon flavor. It was salty and a bit of fizz. Kind of like a salty sprite. Wasn't syrupy though.
Every Wal-Mart, Safeway, King-Sooper, Albertsons, Walgreens around Fort Collins has the magnesium citrate available in the "Digestive" section.
Not sure where you live but Fort Collins always ranks high on the best places to live, best places to retire, etc. lists. Maybe colonoscopy tourism will take off since our gastroenterologists use mag citrate instead of the nasty stuff you guys have been having to use.
Now there's a headline for you: Fort Collins tops list of best cities to get a colonoscopy!
Mike