A sinus infection produces a specific combination of symptoms: cloudy or colored nasal drainage plus either a stuffy/blocked nose or pain and pressure in your face, head, or around your eyes. If you have both of those features, you likely have sinusitis. The trickier question is whether it’s viral (which clears up on its own) or bacterial (which may need antibiotics), and that comes down to how long your symptoms last and whether they follow a particular pattern.
The Core Symptoms
Sinus infections cause a cluster of symptoms that overlap with colds and allergies but tend to feel more localized and intense. The hallmarks are yellow or green discharge from your nose, facial pain or pressure, nasal congestion, a reduced sense of smell, bad breath, and a productive cough that often worsens at night. You don’t need every symptom on that list. The defining combination is colored nasal drainage paired with either congestion or facial pressure.
Where you feel the pain can point to which sinuses are involved. Pain in your cheeks just below the eyes, or even an ache in your upper teeth, suggests your maxillary sinuses (the large ones behind your cheekbones). A headache across your forehead points to the frontal sinuses. Pain behind and between the eyes, sometimes described as a splitting headache, involves the ethmoid sinuses deeper in your skull. Many people have more than one set affected at the same time.
How to Check at Home
You can do a simple pressure test on your own sinuses. Using your thumb, gently press in a circular motion just below the bony ridge under your eyebrows, avoiding the eye socket itself. Then press below your cheekbones, slightly to either side of your nose. A feeling of slight pressure is normal. If either spot produces noticeable tenderness or sharp pain, that sinus is likely inflamed or infected.
This isn’t a substitute for a medical exam, but it helps you pinpoint whether your symptoms are sinus-related or coming from somewhere else, like tension in your temples or jaw.
Viral or Bacterial: The 10-Day Rule
Most sinus infections are caused by viruses, not bacteria. This matters because antibiotics only work on bacterial infections, and the two look almost identical in the first several days. Three patterns suggest a bacterial infection rather than a virus:
- No improvement after 10 days. Viral sinus infections typically start getting better before the 10-day mark. If yours hasn’t budged at all by day 10, bacteria are the likely culprit.
- Severe onset. A fever of 102°F or higher combined with facial pain and colored nasal discharge lasting three to four days points to a bacterial cause from the start.
- Double sickening. You start to feel better around days 4 to 7, then suddenly get worse again. This pattern of improvement followed by a relapse between days 5 and 10 is one of the strongest indicators of a secondary bacterial infection settling in after the initial virus.
If none of those patterns apply, you almost certainly have a viral sinus infection. It will be miserable, but it will resolve on its own, usually within 7 to 10 days.
Green Mucus Doesn’t Mean Bacteria
One of the most persistent misconceptions is that green or yellow mucus means you need antibiotics. It doesn’t. Your mucus changes color as your immune system fights off any invader, viral or bacterial. White blood cells flooding the area release enzymes that tint the discharge green. This is the normal course of any sinus infection and happens with viruses just as readily as with bacteria. The color of your mucus, on its own, tells you almost nothing about whether you need treatment.
Is It Actually a Migraine?
About 90% of people who believe they have sinus headaches actually have migraines. This misdiagnosis is so common because migraines activate the same nerves that supply your sinuses, eyes, ears, and jaw. Nearly half of migraine sufferers experience nasal congestion or watery eyes during an attack, which makes it feel exactly like a sinus problem.
A few features help separate the two. Migraine pain tends to throb or pulsate and gets worse when you move around. It often comes with nausea, vomiting, or sensitivity to light, noise, and smells. Sinus infection pain feels more like steady pressure, centers around your cheeks and eyes, weakens your sense of smell, and typically comes with colored nasal discharge and sometimes a low fever. If your “sinus headaches” keep returning but never come with thick, discolored mucus, you may be dealing with migraines instead.
Another useful distinction: sinus headaches resolve within about a week after the infection clears or after successful antibiotic treatment. If your facial pain lingers or recurs over months without other sinus symptoms, that pattern fits migraine far better.
When Sinus Infections Become Chronic
Acute sinusitis lasts up to four weeks. If your symptoms persist beyond 12 weeks, even at a low level, you’ve crossed into chronic sinusitis. People with chronic sinusitis still have nasal blockage, colored drainage, and facial pain or pressure between acute flare-ups. They never fully return to a symptom-free baseline. This is a different condition that typically requires evaluation to look for underlying causes like nasal polyps, structural issues, or immune factors.
Some people fall in between: they get fully better between episodes but keep getting sinus infections multiple times a year. This is called recurrent acute sinusitis, and it also warrants a closer look at what’s making you vulnerable to repeated infections.
Symptoms That Need Immediate Attention
Sinus infections rarely become dangerous, but the sinuses sit close to the brain and eyes, so infection can occasionally spread. Get medical attention right away if you notice swelling, redness, or pain around your eyes, double vision or other vision changes, a high fever, a stiff neck, or confusion. These symptoms suggest the infection may be moving beyond the sinuses into surrounding tissue, and they require urgent evaluation.