Your health care provider may prescribe medicines to help treat your sinusitis. If you have a bacterial infection, antibiotics are effective treatments. If you are prescribed antibiotics, take all pills on schedule until they are gone. This is important to do even if you feel better. Decongestants help relieve swelling. Use decongestant sprays for short periods only under the direction of your provider. If you have allergies, your provider may prescribe medicines or suggest over-the-counter products to help give you relief.