Sinus Infection Symptoms (Sinusitis)

A sinus infection, also called sinusitis, occurs when the tissue lining the sinuses becomes inflamed and swollen. This inflammation blocks normal mucus drainage and creates an environment where bacteria or viruses can grow. Common symptoms include nasal congestion, thick yellow or green discharge, facial pain or pressure (especially around the eyes, cheeks, or forehead), reduced sense of smell, headache, cough, and fatigue.

• Viral infections: The most frequent cause, often developing after a cold.
• Bacterial infections: Can occur following viral sinusitis or due to prolonged blockage.
• Allergies: Seasonal allergies that cause nasal inflammation.
• Nasal polyps or deviated septum: Physical obstructions that block sinus drainage.
• Environmental irritants: Smoke, pollution, or workplace exposures.
• Risk factors: History of frequent colds, asthma, allergies, smoking, weakened immune system.

See a doctor if symptoms last more than 10 days without improvement, are severe, or worsen after initially improving. Immediate medical attention is needed for sinus infection symptoms accompanied by high fever, vision changes, confusion, swelling around the eyes, or severe headache, which may indicate complications.