Dear Doc: As a bottom, I like to make sure that my anus is thoroughly clean before receiving anal sex. My question is when to stop cleansing? I can spend up to 20 minutes and 30 flushings before the water that comes out and fills the toilet is clear. Is that the proper amount of time and the best way to judge? It just seems that I am cleaning out more than just the large intestine. Thanks. Dick

Dear Doc: As a switch hitter i have always cleaned my colon before anal sex and insist my partner do the same. Plain water does the trick. I realize an "enema" should not be a daily occurrence since essential bacteria exists in the colon and are necessary for good health. The question is - how often is to often and is there anything one could use to limit the removal of those essential bacteria? Thanks, Charles

From the Doctor: These two questions are quite similar, and I was combine the answers. First, there are really no medical guidelines on this issue; common sense must combine with a bit of medical knowledge.

Tap water flushing before anal intercourse is a must, as is protection from STDs, including HIV. "Good" bacteria live in the colon. Flushing with a bulb syringe will clean out the rectosigmoid, the lower part of the colon. Cleansing that part, even daily, is unlikely to damage the normal bacterial population of the rest of the colon. However, 30 flushings seems excessive. You do not nor do you need to clean the entire colon. Anyway, that's essentially impossible without using more than a bulb.