A sinus infection occurs when the lining of the sinus cavities becomes inflamed, making it harder for mucus to drain normally. This can create pressure and discomfort and, in some cases, lead to infection.
Sinus infections may be:
- Acute (lasting up to 10 days)
- Subacute (lasting 10 days to 4 weeks)
- Chronic (lasting longer than 12 weeks)
- Recurrent (multiple infections over the course of a year)
Not all sinus symptoms are caused by infection. Allergies, structural issues, or chronic inflammation can produce similar symptoms, which is why evaluation is often helpful.
