Published July, 2014 (revised October 20, 2023)
Fleet enemas are commonly used in both healthcare facilities and in the home to relieve constipation. These seemingly safe treatments are available over-the-counter (OTC). As shown in figure 1, the product label says, “Fleet Enema Saline.” This would lead you to believe that the enema was basically made of saline (salt or sodium chloride and water). However, this product actually contains phosphate which can cause bad side effects, especially in elderly people or those with kidney disease.
A few years ago, we received a report about an elderly woman who had been admitted to a hospital with acute renal (kidney) failure. She also had constipation and received 2 regular Fleet enemas. Soon after, her blood phosphate levels rose and her calcium blood levels became extremely low. She required daily hemodialysis, a process to remove wastes and electrolytes, Including the excess phosphate, from the blood when the kidneys are not functioning properly. The woman recovered and was transferred to a long term care facility.
In March 2013, the Department of Veterans Affairs (VA) reported a case involving a man who received multiple Fleet enemas in less than 12 hours. He developed high sodium and low calcium blood levels. He became dehydrated and his kidneys stopped working. He later died. Phosphate-containing enemas cause fluid to move into the colon, or the large intestine, to help relieve constipation. Under normal conditions the enema response typically occurs within minutes. However, some medicines and diseases may allow the enema to be retained for a longer period of time. This enables the phosphate to be absorbed and increases the risk of developing other problems. Elderly patients and patients with kidney disease are also at risk. These enemas may cause these patients to become quickly dehydrated, and cause their blood levels of phosphate, sodium, and calcium to be abnormal.
Here’s what you can do: To prevent constipation, eat a well-balanced, high fiber diet; drink plenty of fluid (unless restricted for another medical reason); and exercise regularly. If you become constipated, drink extra water (unless restricted). Try drinking warm liquids, especially in the morning. Increase your fiber intake by eating more fruits and vegetables, or adding prunes or bran cereal to your diet. Talk to your doctor or pharmacist about taking an OTC stool softener, such as Colace (docusate). Do not use these products for more than 2 weeks. Call your doctor if this problem continues, you have blood in your stools, or if you have severe pain with bowel movements. If you are instructed to use an enema, discuss with your pharmacist which one would be best for you. Read the directions before using the product. Do not use more than one enema in a 24-hour period.
