Dear Dr. Roach: How effective is premedication for dental work? Because of mitral valve surgery I had 11 years ago, I always take antibiotics before dental procedures. This past March, I did the normal protocol. Within a few weeks, I developed a low-grade temperature. I did not pay attention to it, thinking it would go away, until I developed a 103-degree temperature with chills and shaking. I had bacterial endocarditis. May I presume that the endocarditis came from the dental work, despite the antibiotics?
Dear N.I.: Endocarditis, infection of a heart valve, is a rare event after dental procedures with or without antibiotics. Bacteria can transiently enter the blood after brushing teeth or having a bowel movement. In your case, it is much more likely that it was not the dental procedure, according to the most recent guidelines from the American Heart Association. They stress these points (and I am paraphrasing): Antibiotics may prevent an exceedingly small number of cases of infection, if any, in individuals who undergo a dental or other procedure. The risk of antibiotic-associated adverse events exceeds the benefit, if any, from prophylactic antibiotic therapy.
Because of this, the AHA now recommends antibiotics only for people with very high risk conditions: a history of endocarditis, people with a prosthetic heart valve or prosthetic material used in surgery, people with a heart transplant and valve disease, and unrepaired congenital heart disease. Only dental procedures expected to cause bacteria in the blood would call for antibiotics, and not procedures such as anesthetic injections or X-rays.
Dear Dr. Roach: After two close calls with blood clots in the lungs, my husband has been put on Coumadin permanently. He is in a lot of pain from arthritis and needs something for pain. Is there anything he can take?
Dear R.M.C.: Warfarin (Coumadin and others) reduces the bodyís ability to make blood clots by blocking the effect of vitamin K in the liver. So, substances that affect the liverís ability to metabolize, such as Tylenol, or that affect the platelets, such as aspirin, tend to increase the propensity to bleed.
Fortunately, in most people, modest doses of pain medications still can be safe. Significant effect on blood clotting in people on warfarin is rare if taking less than 2,000 mg of acetaminophen (thatís four extra-strength or six regular tablets) daily. Most arthritis medicines are still safe on warfarin, but double-check with his doctor before he takes them. Tramadol also usually is safe.
Email questions to ToYourGoodHealth@med.cornell.edu.