A sinus infection may have spread to the brain if symptoms become severe, unusual, or neurological. Warning signs include a very bad or worsening headache, fever that does not go away, stiff neck, confusion, extreme sleepiness, seizures, fainting, weakness on one side of the body, slurred speech, personality changes, or new vision problems.
This complication is rare, but it can be life-threatening. A sinus infection can sometimes lead to meningitis, a brain abscess, or infection around the brain, especially when symptoms get worse instead of improving or appear suddenly after a period of feeling better.
Typical sinus symptoms, such as facial pressure, congestion, thick nasal drainage, or mild headache, do not usually mean the infection has reached the brain. However, severe headache with fever, vomiting, neck stiffness, confusion, seizure, or any change in alertness should be treated as an emergency.
Anyone with these symptoms should go to the ER or call 911 right away. Do not try to treat possible brain-related complications at home or rely on leftover antibiotics. A doctor may need urgent imaging, IV antibiotics, and specialist care from an ENT doctor, neurologist, or neurosurgeon.