Pharyngitis or tonsillitis, a throat infection that usually presents with a sore throat, is a common upper respiratory tract infection. Most sore throats are caused by viruses, but sometimes bacteria are involved. Many people carry bacteria in their throat without becoming ill. However, sometimes a bacterial throat infection can occur.
Infection with a specific type of bacteria, group A beta-haemolytic streptococci (GABHS) is linked to serious complications such as acute rheumatic fever or kidney disease (post-streptococcal glomerulonephritis). In order to prevent these complications antibiotics are often prescribed to treat patients presenting to their doctor with a sore throat. A previous Cochrane review found that there is only a modest benefit of antibiotics for treating an acute sore throat, even if group A beta-haemolytic streptococci (GABHS) are present. Most throat infections, even with bacteria, are self-limiting and the risk of complications is extremely low in most populations studied (in low-income countries). However, sometimes antibiotics may be indicated.
We found 17 trials with a total of 5352 participants that studied the effects of different classes of antibiotics on resolution of symptoms in patients with a sore throat and a positive culture for GABHS. Our review found that the effects of these antibiotics are very similar. All antibiotics studied also cause undesired side effects (such as nausea and vomiting, rash), but there was no strong evidence for meaningful differences between the antibiotics. The studies did not report on long-term complications and therefore it is unclear if any class of antibiotics is better in preventing these serious but rare complications.
As all the identified studies were carried out in populations in high-income countries with a low risk of streptococcal complications, there is a need for trials in populations where this risk is still very high (low-income countries and Aboriginal communities). Penicillin has been used for a very long time but resistance of the GABHS to penicillin has never been reported. Also, penicillin is a cheap antibiotic. Our review therefore supports the use of penicillin as a first choice antibiotic in patients with acute throat infections caused by GABHS.