Enema - How to Use Medical Enema ? with Sodium Phosphate Solution

Phosphate enemas have been used in the community for over 30 years to relieve constipation. However, like all enemas, their insertion is invasive, embarrassing, and often uncomfortable for the patient, while the amount of fluid involved means they have a tendency to be messy.

Phosphate enemas contain sodium acid phosphate and sodium phosphate. The osmotic activity of the former increases the water content of the stool so that rectal distension follows and it is thought that this induces defecation by stimulating rectal motility (Roe, 1994; Barrett, 1993). The enemas are usually effective within 5-10 minutes, which limits the risk of phosphate toxicity as the enema fluid is evacuated with the stool.