Most shower enemas work in basically the same way, although they may be used for different reasons. They may be performed before a medical procedure, when one is very constipated, as part of a colon cleanse, or to help prevent polyps. Although effective, shower enemas do carry certain risks and should only be performed after a doctor has given the okay.
These enemas require the use of a long nozzle combined with tubing which attaches to the shower head. They also feature a valve which controls the flow of water. This helps prevent the colon from becoming too full, as well as preventing the water from entering with too much force. It is important to follow the instructions for performing the enema very carefully, as doing something wrong could lead to serious or even life-threatening injury.
The use of shower enemas is most often related to relieving chronic constipation. It is often much less expensive than buying numerous disposable enemas or going to the doctor to have them performed. Those who are about to undergo a medical procedure or who have frequent procedures may also benefit from the long-term use of an enema since they can be reused many times.
Occasionally, shower enemas may be recommended for the purpose of colon cleansing because they are usually able to reach farther into the large intestines than most conventional enemas. This allows more debris and compacted material to be removed at once. Doing this may be beneficial for some, but the procedure carries risks and should not be performed except when following a doctor's instructions.
There is some evidence that performing routine enemas may help prevent polyps -- growths which occur in the colon. They are often precancerous and are normally removed by a doctor to prevent the development of colon cancer. Those who are at high risk of developing polyps or colon cancer should receive a physical exam before performing a shower enema unless advised by a doctor.
Risks associated with shower enemas may include rupture of the colon. It is also possible for the colon to absorb too much moisture, which will then be distributed throughout the body. This can lead to swelling, or edema. Additionally, too much water in the body can throw off the blood's electrolyte balance.