A sinus infection typically announces itself with a combination of facial pressure or pain, thick discolored nasal discharge, and congestion that persists well beyond what a normal cold should last. The key distinction is timing: if your symptoms have dragged on for more than 10 days without improving, you’re likely dealing with a sinus infection rather than a simple cold. Here’s how to tell what’s going on and when it matters.
The Core Symptoms to Look For
Sinus infections produce a recognizable cluster of symptoms. Clinicians use a checklist of “major” and “minor” signs to make the diagnosis, and you can use the same framework at home. A sinus infection is likely if you have at least two major symptoms, or one major symptom plus two or more minor ones.
The major symptoms are:
- Thick, discolored nasal discharge (yellow, green, or grayish, draining from the front of your nose or down the back of your throat)
- Nasal congestion or blockage that makes it hard to breathe through your nose
- Facial pain or pressure (more on where this shows up below)
- A feeling of fullness or congestion in your face
- Reduced or lost sense of smell
- Fever
The minor symptoms are headache, ear pain or pressure, bad breath, upper tooth pain, cough, and fatigue. On their own, these are vague. Paired with the major symptoms above, they strengthen the picture considerably. Tooth pain in your upper jaw, for example, is a surprisingly common sinus symptom because the roots of those teeth sit right beneath your cheek sinuses.
Where the Pain Shows Up
Your sinuses are air-filled pockets in four different locations around your nose and eyes, and the location of your pain points to which set is inflamed:
- Forehead pain: frontal sinuses, just above your eyebrows
- Pain between or behind your eyes: sphenoid sinuses, deep in the skull, or ethmoid sinuses along the bridge of your nose
- Cheekbone pain or upper tooth pain: maxillary sinuses, the large cavities beneath your cheeks
- Ear pressure or fullness: often linked to sphenoid sinus inflammation
The pressure often gets noticeably worse when you lean forward or bend down. That shift in position increases pressure on already-swollen, fluid-filled sinuses. If bending over to tie your shoes makes your face throb, that’s a telling sign.
Sinus Infection vs. a Cold
Most sinus infections start as colds. A virus inflames your nasal passages, mucus builds up, and the warm, moist, stagnant environment can become a breeding ground for bacteria. The tricky part is that the early days of a sinus infection look identical to a regular cold. Three patterns help you tell the difference.
The 10-day rule. A typical cold improves noticeably within 7 to 10 days. If your congestion, facial pressure, and discharge are no better after 10 days, that’s the most common signal that a bacterial sinus infection has developed.
Severe onset. A high fever (above 102°F / 39°C) combined with thick, colored nasal discharge or significant facial pain that lasts 3 to 4 consecutive days from the start of illness suggests bacteria from the beginning, not just a lingering virus.
Double sickening. This is the pattern people describe as “I was getting better, then I got worse again.” You start with a normal cold, feel like you’re turning the corner after several days, and then your congestion, discharge, or cough flares back up. That second wave strongly suggests a bacterial infection has taken hold on top of the original virus.
The Mucus Color Myth
Green or yellow mucus is one of the most widely cited “signs” of a sinus infection, but it’s not as reliable as most people think. Both viral and bacterial infections cause discolored mucus. The color comes from immune cells and the enzymes they release as they fight infection, not from bacteria specifically. A plain cold can produce vivid green mucus for days. So while thick, discolored discharge is part of the picture, it alone doesn’t confirm a bacterial infection, and it’s not a reason to seek antibiotics. The timing and severity patterns described above are far more useful.
Sinus Infection vs. Allergies
Allergies and sinus infections share congestion and pressure, which is why people often confuse them. Two symptoms reliably separate the two: itching and sneezing. Allergies cause itchy eyes, itchy nose, and frequent sneezing fits. Sinus infections generally do not. If your eyes and nose itch and you’re sneezing constantly, allergies are the more likely culprit. If your main complaints are facial pain, thick discharge, and a reduced sense of smell without itching or sneezing, a sinus infection fits better.
Allergies can also set the stage for sinus infections. Prolonged allergic inflammation swells the sinus openings shut, traps mucus, and creates conditions where bacteria thrive. So if you have allergies and then develop facial pain, fever, or worsening discharge after 10 days, both may be happening at once.
Acute vs. Chronic Sinus Infections
An acute sinus infection typically resolves within 10 days, and even bacterial cases usually clear within a few weeks with or without antibiotics. If your symptoms persist for 12 weeks or longer, that crosses into chronic sinusitis, which is a different condition with different causes. Chronic sinusitis often involves structural issues like nasal polyps, ongoing allergic inflammation, or immune system factors. It requires a more thorough evaluation, often including imaging or a direct look inside the nasal passages with a small camera.
What to Expect for Treatment
Most acute sinus infections, even bacterial ones, resolve on their own. Initial management typically focuses on symptom relief: saline nasal rinses to flush out mucus, nasal decongestant sprays for short-term use, and over-the-counter pain relievers for facial pressure and headache. Antibiotics are generally reserved for cases that meet the bacterial criteria described above, particularly the 10-day rule, severe onset, or double sickening pattern. Even then, guidelines emphasize that watchful waiting for a few additional days is reasonable for mild to moderate cases.
Symptoms That Need Immediate Attention
Sinus infections rarely become dangerous, but the sinuses sit close to the eyes and brain, so complications can be serious when they occur. Get medical attention right away if you notice swelling or redness around your eyes, double vision or other vision changes, a high fever that won’t break, a stiff neck, or confusion. These can indicate the infection has spread beyond the sinuses and needs urgent treatment.