Plain language summary
Different antibiotics for group A streptococcal pharyngitis
We wanted to know which antibiotic was more effective in treating sore throats caused by bacteria (group A beta-haemolytic streptococci (GABHS)).
Most sore throats are caused by viruses, but many people carry throat bacteria, sometimes causing bacterial throat infection.
GABHS infection can have serious complications including rheumatic fever and kidney disease. Antibiotics are often prescribed to prevent complications, but provide modest benefit for sore throat, even if GABHS are present. Most throat infections are self-limiting and complication risks is extremely low for most people in high-income countries. However, sometimes antibiotics are needed. Penicillin, a cheap antibiotic, has been used to treat GABHS for many years. GABHS resistance to penicillin is rare.
We searched the literature to March 2016.
We included 19 trials (18 publications) that involved 5835 people. Trials studied different antibiotics for people with sore throat who tested positive for GABHS, and were aged from one month to 80 years. Nine trials included only children; and nine included people aged 12 years or older. Most studies were published over 15 years ago; all but one reported on clinical outcomes.
Study funding sources
Thirteen trials were supported by drug study funding - some received grants - others included people employed by drug companies. Five studies did not report funding.
Antibiotic effects were similar, and all caused side effects (such as nausea and vomiting, rash), but there was no strong evidence to show meaningful differences between antibiotics. Studies did not report on long-term complications so it was unclear if any class of antibiotics was better in preventing serious but rare complications.
All studies were in high-income countries with low risk of streptococcal complications, so there is a need for trials in low-income countries and Aboriginal communities where risk remains high. Our review supports the use of penicillin as a first choice antibiotic in patients with throat infections caused by GABHS.
Quality of the evidence
Evidence quality was low or very low for all outcomes when macrolides or cephalosporins were compared with penicillin. Evidence quality was downgraded because of concerns about randomisation and blinding, wide confidence intervals (estimates were not very precise) and statistical differences among studies that may impact on the validity of the estimate. Most study authors did not report enough information about methods to be sure there was no bias.