Sinusitis is one of the most common reasons for visiting a doctor and an estimated 20 million cases of acute sinusitis occur every year in the USA alone. There are four pairs of sinuses linked to the bony structures around the nose: maxillary, frontal, ethmoidal and sphenoidal sinuses. In sinusitis, these membrane-lined air spaces become infected, which causes pain and discharge from the nose. Treatment options include decongestants, steroid drops or sprays, mucus-clearing drugs (mucolytics), antihistamines and antibiotics and sometimes sinus puncture and irrigation for removal of purulent secretions.
In most cases sinusitis occurs during viral infections where antibiotics are ineffective, but the few cases that also have a bacterial infection (one or two out of every 100 patients with sinus symptoms) could benefit. Unfortunately it is difficult to distinguish between those who have a bacterial infection and those who do not. It is important to avoid unnecessary use of antibiotics and limit the potential for antibiotic resistance.
This updated review compiled data from 63 separate studies that used a variety of antibiotics for simple maxillary sinus infection, i.e. non-complicated acute sinusitis in a person with a healthy immune system. Nine of the studies compared antibiotics to placebo (1915 participants; seven of the studies conducted in primary care), and 54 studies compared different classes of antibiotics. Five of the nine placebo-controlled studies involving 1058 participants found that most participants got better within two weeks, regardless of whether they received the antibiotic or not (roughly 9 out of 10 participants in antibiotic groups and 8 out of 10 in placebo groups). Although all the five studies in this main outcome were assessed as having low risk of bias, the overall evidence was assessed only as being of moderate quality (it is possible that a new large study can change the estimate). In the remaining 54 studies comparing different antibiotics (10 different comparisons), no antibiotic was found to be superior to another. The evidence is current to March 2013.
The small benefit gained by antibiotics may be overridden by the negative effects of the drugs. In addition to patient-related adverse effects (like skin rash and gastrointestinal problems such as diarrhea, abdominal pain and vomiting), side effects include the risk of increased resistance to antibiotics amongst community-acquired pathogens (bacteria).