Do I need antibiotics for a sinus infection?
Last updated September 3, 2026.
Usually no - most sinus infections are viral and clear without antibiotics. The CDC lists the patterns that justify them: symptoms past 10 days without improving, symptoms that worsen after getting better, or fever lasting more than 3 to 4 days. Even in those cases, many clinicians suggest watching for 2 to 3 more days or writing a delayed prescription you fill only if things do not improve, because unneeded antibiotics carry real harm, from rashes to C. diff. What actually helps while you wait: saline rinses, rest, fluids, and over-the-counter pain relief. Pymander is a free AI doctor, 24/7 by text, and can map your timeline onto these patterns so you know whether to get seen.
Sinus infection dragging on? Text a free AI doctor about your timeline
Start a free AI doctor consult →What to do
- Mark day 10 on your calendar: not improving by then is the clearest antibiotic signal.
- Watch for double-worsening: getting better, then slamming back worse, suggests bacteria followed a virus.
- Track fever days: fever beyond 3 to 4 days changes the answer.
- Use saline rinses and fluids meanwhile: they ease symptoms whether the cause is viral or bacterial.
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