Antihistamines only cure sinusitis on television, or when it is due to allergic rhinitis. Do not allow patients to use decongestant nose drops more than 3 days, thereby allowing their nasal mucosa to become habituated to sympathomimetic medication. Do not prescribe topical or systemic sympathomimetic decongestants to a patient who suffers from hypertension, tachycardia or difficulty initiating urination, all of which may be exacerbated. The paranasal sinuses drain through tiny ostia under the nasal turbinates which, if occluded, allow secretions and pressure differences to build up, resulting in pressure and pain of acute sinusitis, and the air-fluid levels sometimes visible on upright x rays. Sinus infections are relatively common and complications relatively rare, but the bony walls of the paranasal sinuses are so thin that bacterial infections can spread through them.
Most sinusitis begins with mucosal swelling from a viral upper respiratory infection.
Other causes include dental infection, allergic rhinitis, barotrauma from flying, swimming or diving, nasal polyps and tumors and foreign bodies, including nasogastric and endotracheal tubes in hospitalized patients. Abscessed teeth can be the source of a maxillary sinusitis. If there is tenderness to percussion of the bicuspids or molars, arrange for dental referral. Complications such as orbital cellulitis, osteomyelitis, epidural abscell, meningitis, cavernous sinus thrombosis and subdural empyema can be devastating and therefore patients must be instructed to get early follow up when signs and symptoms worsen or do not improve in 48-72 hours, or if there is any change in mentation. Frontal sinusitis has the greatest potential for serious complications, particularly in adolescent males, the group at greatest risk for intracranial complications.br Computerized tomographic scanning of the sinuses is more accurate than plain x rays, particularly when evaluating the ethmoid or sphenoid sinuses, but CT scans are needed from the ED only in unusual circumstances.