In most cases, sinusitis is caused by viral infections or allergies. These types of sinus infections tend to improve without medication after a week or so. Symptoms like headaches and congestion can typically be improved with over-the-counter (OTC) antihistamines, decongestants, nasal steroids, and pain relievers.
Occasionally, sinus infections can be caused by bacteria. Before assessing the need for antibiotics, your doctor may wait and observe whether your acute sinusitis worsens. Antibiotics may be prescribed if your symptoms are severe, progressive, or chronic.