If a patient has upper respiratory tract infection, ear infection or sore throat, the physician should not prescribe antibiotics just because he/she wants to prevent complications, according to an article published in the British Medical Journey (BMJ). However, as far as the elderly are concerned, antibiotics do significantly lessen the risk of pneumonia following a chest infection.

The authors explain that the greater part of antibiotic prescribing is done in primary care, and mostly for common respiratory tract infections. Guidelines in the UK recommend against the routing prescribing of antibiotics for patients with sore throat, ear infection, and upper respiratory tract infection. The guidelines do advise they be used for pneumonia.

During the period 1994-2000 the prescribing of antibiotics for upper respiratory tract infections in the UK in general practice fell by 45%. However, 67% of respiratory tract infection patients were still being prescribed antibiotics, as were 80% of those with ear infections, 60% of those with sore throat, and 47% of those with upper-respiratory tract infections.

The authors explain that their study indicates that there is a significant gap between evidence based guidance and GPs’ prescribing habits.

The researchers identified 3.36 million cases of respiratory tract infection during 1991-2001 from the UK General Practice Research Database and tried to find out whether patients who received antibiotics had fewer complications than those who did not.

The researchers recorded risk of serious complication during the month following diagnosis, including infection of the mastoid bone after ear infection (mastoiditis), abscess at the back of the throat after sore throat (quinsy), and pneumonia following upper-respiratory tract infection and chest infection. They also recorded how many patients were needed to treat (give antibiotics to) to prevent one complication.

The risk of serious complication following upper respiratory tract infections, ear infections and sore throat was small, report the researchers. Although antibiotics reduced the risk, 4,000 prescriptions were needed to prevent one single complication.

On the other hand, the risk among the elderly of developing pneumonia after chest infection was high, and antibiotics did significantly reduce this risk. For every 39 patients over 65 years who received antibiotics one complication was prevented.

The researchers did not detect a significant difference in risk for smokers, patients with chronic respiratory disease, or people with cardiac disease.

The authors conclude that a GP should not base his/her reason for prescribing antibiotics for ear infection, upper respiratory tract infection or sore throat on the idea that this will have an impact on preventing serious complications. Where the prescribing of antibiotics to prevent complications is justifiable, they add, is to lower the risk of pneumonia after chest infections, especially when the patient is elderly.

In an Accompanying BMJ Editorial, scientists from the University of Antwerp say that the majority of infections can be managed by watchful waiting.

“Protective effect of antibiotics against serious complications of common respiratory tract infections, assessed using the UK General Practice Research Database”
BMJ Online First doi:10.1136/bmj.39345.405243.BE
Click here to view abstract online

“Editorial: Antibiotics for respiratory tract infections in primary care”
BMJ Online First doi:10.1136/bmj.39357.571343.80
Click here to view abstract online

Written by: Christian Nordqvist