YOUR HEALTH
Antibiotics can bring about serious diarrhea
DR. DONOHUE

DEAR DR. DONOHUE: Will you discuss Clostridium difficile infection? Are some antibiotics more likely to cause it than others? I took 10 days of clindamycin for an abscessed tooth. Four weeks after finishing the clindamycin, I thought I had a stomach virus. I became very ill eight days later. The doctor ran a test for C. difficile toxins, and I had them. I was put on metronidazole. Even now when I have to go to the bathroom, it is with great urgency once or twice a day. My stools are very soft. -- A.R.

ANSWER: Clostridium difficile infection has gone by many names -- antibiotic-associated colitis, pseudomembranous colitis, C. difficile-associated diarrhea. In the United States, more than 300,000 people suffer from it yearly.

About 3 percent of healthy adults harbor the Clostridium difficile bacterium in their colon. When a person with this germ takes an antibiotic for some unrelated condition -- as you did for an abscessed tooth -- the antibiotic can kill good colon bacteria and allow the C. difficile bacterium to flourish and take over the colon. This germ produces toxins (poisons) that can bring on diarrhea.

Any antibiotic can give rise to a C. difficile infection, but ones that are often implicated include clindamycin (Cleocin), ampicillin, quinolones (Cipro is one example) and cephalosporins.

The illness comes on either while taking the antibiotic or up to six weeks after having stopped antibiotic treatment. Stomach cramps, fever and diarrhea are the signs. For most, stopping the antibiotic brings a cure. Others with more-severe symptoms have to take metronidazole or vancomycin, two drugs that target the difficile germ. Sometimes probiotics -- foods or preparations of good bacteria -- are used in conjunction with these medicines. In extreme cases, the colon has to be removed.

This infection has a tendency to relapse after treatment, so repeated treatments often are necessary. I don't know why you're still having trouble. It might be only a matter of your colon regaining its normal function after having had this infection.

DEAR DR. DONOHUE: My knee can give out on me for no reason. I haven't fallen, but I'm afraid I might. What's the reason for this? -- N.P.

ANSWER: Yours is a common complaint of middle-aged or older people, and they often have painful osteoarthritis of that knee. Other possibilities are a tear of one of the knee ligaments or a kneecap that has worked its way out of its normal groove. Falling is a justified fear.

Have your doctor check for these conditions. Strengthening the front thigh muscles -- the muscles greatly involved with knee stability -- can stop the buckling and remove the threat of falling.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL32853-6475. Readers may also order health newsletters from www.rbmamall.com. 2006 North America Syndicate Inc. All Rights Reserved