The American Academy of Otolaryngology-Head and Neck Surgery classifies sinusitis into acute, subacute, acute recursive, and chronic types based on the duration of the disease course. Acute sinusitis is then subdivided into acute bacterial sinusitis (ABS) and acute viral sinusitis (AVS) based on the cause.

This review will discuss aspects of rationalization, benefits, and risks of antibiotics in acute sinusitis treatment.

Rationalization of Antibiotics in Acute Sinusitis Treatment

The Infectious Disease Society of America guidelines states that the administration of empirical antibiotic therapy should begin immediately when the clinical diagnosis of Acute Bacterial Sinusitis  (ABS) has been established.

ABS can be distinguished from AVS if one of the following three criteria is met:
- The disease lasts more than ten days with persistent symptoms or typical signs of acute sinusitis without showing any clinical improvement.
- There is a high fever above 39C,  purulent secretions from the nose, and facial pain that lasts for at least 3-4 days in a row since symptoms appear.
- there is a new episode of fever accompanied by headache or increased nasal secretions following an episode of upper respiratory tract infection due to a virus that lasts 5-6 days after previously experiencing clinical improvement.

In addition, the National Institute of Health and Care Excellence recommends that antibiotic administration should also be considered in groups of patients at high risk of complications due to acute sinusitis, namely:
  • Patients with preexisting comorbidities, such as neuromuscular, kidney, heart and lung disease
  • Patient in immunosuppressed condition
  • Cystic fibrosis patients
  • Patients over 65 years with symptoms of cough, accompanied by two or more risk factors.
  • Patients over 80 years with at least one risk factor: (history hospitalized in the last 12 months, type 1 or 2 diabetics, cardiac failure congestion, and history of oral corticosteroid use).

Scientific evidence about the indication of antibiotics for the treatment of acute sinusitis in children is minimal. However, from several randomized clinical trials, estimations of the effectiveness of antibiotics in treating acute sinusitis in children are similar to adults.

Benefits of Antibiotics in Treating Acute Sinusitis

Apart from the rationalization of antibiotics for sinusitis that has been described previously, recent evidence from various randomized controlled clinical trials shows that the use of antibiotics has little benefit in the treatment of acute sinusitis.

Ahovuo-Saloranta et al. in their review found six randomized controlled studies comparing antibiotics to placebo to treat acute sinusitis with the following findings:
A meta-analysis of 5 studies (n = 631) showed that there was no clinically meaningful improvement in 7-15 post-treatment by giving antibiotics compared with placebo. Antibiotics were seen to show benefits, supported by the relative risk of therapy failure of 0.66 (95% CI 0.44 to 0.98). However, it should be noted that the rate of clinical improvement was quite high in both groups, namely 86% in the placebo group vs. 91% in the antibiotic group.

On the other hand, antibiotics appear to be able to reduce the risk of failure of clinical improvement within 1-2 weeks by 27% (95% CI 15-37%) when compared to placebo. However, how far this is clinically meaningful still needs to be studied further.

A systematic review by Falagas et al. of 17 controlled clinical trials comparing antibiotics with placebo in treating acute sinusitis found that:
Sixteen studies (n = 2648) showed that antibiotic therapy significantly improved cure rates 7-15 days after starting therapy (OR 1.64; 95% CI 1.35-2.00)
However, researchers in this study concluded that the benefits of antibiotics were relatively small compared to placebo given that the proportion of patients recovering was relatively similar in the antibiotic group compared to placebo (77.2% vs. 67.8%)

Rosenfeld et al. in their study found that:
The cure rate in the first 7-15 days after therapy did not differ significantly between patients who received antibiotics compared with placebo (91% vs. 86%)
Antibiotic therapy is needed for 11-15 patients to demonstrate the benefits of antibiotics in 1 person.
The duration of the pain and symptoms of ABS-related diseases is not related to initial management (observation of symptoms in 7 days without antibiotics vs. administration of antibiotics during clinical diagnosis)
There is currently no clinical evidence to suggest that increasing age, history of allergic rhinitis, or elderly patients are predictors of the benefits of antibiotics in the case of ABS.

Risks of Antibiotics Administration in Acute Sinusitis

Some randomized controlled clinical trials show an increased risk of unexpected events from antibiotics, compared with placebo, in the case of ABS.
Unexpected event rates for various types of antibiotics used in SBA therapy vary greatly between 8-59% and depend on the type of antibiotic used.
The most frequent unexpected event is related to the gastrointestinal tract. However, patients with ABS who receive antibiotics can also experience skin rashes, vaginal yeast infections, headaches, and dizziness.
Giving antibiotics increases the rate of unexpected events by 10-12% compared with placebo with OR 1.8-2.1
Although the administration of antibiotics was associated with an increase in unexpected events, there was no difference between the groups of patients who received antibiotics and placebo in terms of the drop-out rate (1.5%) of the study.
However, in various studies on the monitoring of antibiotic side effects in acute sinusitis therapy studies, it should be noted that less than half of the studies show a standard reporting system for antibiotic side effects. Thus, it is still possible that the unexpected event level of antibiotic use in ABS therapy is the same or exceeds the benefits of the treatment itself.

Clinical diagnosis to distinguish ABS from AVS is the primary key in the initial consideration of whether or not antibiotic therapy is needed in handling ABS cases
The administration of antibiotics shows little benefit compared to placebo in the treatment of ABS, especially in terms of improvement of clinical symptoms decreasing the risk of treatment failure
There is an increased risk of unexpected events from antibiotics compared to placebo in ABS patients by 10-12%
The level of unexpected events varies greatly for each type of antibiotic used in ABS therapy
Gastrointestinal symptoms, skin rashes, vaginal yeast infections, and headaches are common side effects of antibiotics
Until now, monitoring of side effects from the use of antibiotics in ABS is still limited