How long do the effects of a fleet enema (sodium bisphosphate) last for?

Briefly: Fleets enemas work by causing distension of the rectum, leading to evacuation of the contents of the rectum. If you have had a fecal impaction, you may have loose stools for a day or two. A sensitivity to the chemicals in the fleets may cause a mild inflammation in the rectum that should resolve over a brief time. Any continued symptoms may warrant an evalustion by a doctor.

Couple hours: Usually the bowel stimulant effect of a fleet enema (sodium bisphosphate) will only last a couple hours.

Not long: The effects of the Fleet's enema would be measured in hours. Certainly It will wear off by the next day. Good luck.