Why not give anitbiotics for all sore throats?

DEAR DR. DONOHUE: What makes a strep throat so different from other sore throats? Our doctor almost never treats our sore throats with antibiotics because he says most sore throats are not strep throats, and antibiotics don't help. Why not? I feel cheated. -J.K.

ANSWER: Your doctor is doing an admirable job of treating you correctly and preventing the emergence of bacteria resistant to antibiotics. He's also protecting you from developing an allergy to antibiotics. If you did become allergic to one, you wouldn't be able to take when it was indicated.

Only about 10 percent of all adult sore throats are strep throats. A strep throat is one caused by the bacterium with the name streptococcus (STREPtoe KOK-us). With children, the incidence of strep throat is higher, between 15 percent and 30 percent of all sore throats. The overwhelming numbers of sore throats are viral, and antibiotics do not touch viruses.

Even a strep throat gets better with no treatment. Treatment, however, prevents rheumatic fever, a consequence of strep throat infection in a small number of people (less than 3 percent). Rheumatic fever can damage heart valves, and for that reason, doctors are on their toes to distinguish between a viral and a strep sore throat.

They can do so by looking for a number of giveaways. Strep throats almost always cause a fever higher than 100.4 F, and they usually produce pus on the tonsils or back of the throat. They almost never cause a cough. They enlarge neck nodes and make them tender. They are most frequently seen between the ages of 3 and 14.

If the doctor suspects a strep throat, then the next step is to provide proof either by sending a culture of a throat swab to the lab to grow the strep germ or by doing an in-office, rapid test for the detection of the strep germ. If either is positive, penicillin is the drug of choice.

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, FL 32853-6475.