A sinus infection typically announces itself with a specific combination: thick nasal discharge, a blocked nose, and pain or pressure in your face. Having just one of those, like facial pressure alone, isn’t enough to point to sinusitis. You generally need at least two of those core symptoms occurring together, and they need to involve your nose, not just your head.
The Four Main Symptoms
Sinus infections inflame the hollow spaces behind your forehead, cheeks, and nose. That swelling traps mucus, blocks normal drainage, and creates the hallmark symptoms. The standard diagnostic criteria require at least two of the following:
- Nasal congestion or blockage that makes it hard to breathe through your nose
- Thick nasal discharge or mucus draining down the back of your throat
- Facial pain, pressure, or fullness, especially around the cheeks, forehead, or between the eyes
- Reduced or lost sense of smell
You might also notice headaches, a sore throat from postnasal drip, or a cough that worsens when you lie down. These are supporting clues, not defining ones. The diagnosis hinges on what’s happening in and around your nose.
Where You’ll Feel the Pressure
You can get a rough sense of which sinuses are involved by pressing gently on specific spots. Using your thumb, apply light circular pressure just below your eyebrows, along the bony ridge above your eyes. That’s where your frontal sinuses sit. Then press just below your cheekbones, slightly to either side of your nose. Those are your maxillary sinuses. A slight sense of pressure is normal, but sharp tenderness or pain at either location suggests inflammation in that sinus cavity.
Many people describe the pain as a deep, dull ache that gets worse when they bend forward. It can also radiate to your upper teeth, which makes some people initially think they have a dental problem.
Is It a Cold, Allergies, or a Sinus Infection?
Most sinus infections start as a common cold. A typical cold peaks around days three to six, then gradually improves. If your symptoms are still getting worse after a week, or if they haven’t cleared up at all by day ten, you’ve likely crossed into sinus infection territory. The virus has caused enough swelling and mucus buildup for bacteria to take hold.
There’s also a pattern called “double worsening” that’s a strong signal. You start feeling better after a cold, then around day five or six, everything gets worse again: the congestion returns, the discharge thickens, the facial pressure ramps back up. That second wave suggests a bacterial infection has developed on top of the original virus.
Allergies can feel similar because they also cause congestion, pressure, and discharge. The key differentiator is itchiness. Itchy, watery eyes, an itchy nose, and frequent sneezing point toward allergies. Itchiness is rarely part of a sinus infection. Allergies also tend to produce thin, watery discharge, while sinus infections produce thicker, sometimes discolored mucus. And allergies don’t cause fever.
Green Mucus Doesn’t Mean What You Think
Many people assume that yellow or green mucus is proof of a bacterial infection. The reality is more complicated. In one study of patients with acute cough, only 16% of people with yellow or green mucus actually had a confirmed bacterial infection. Green mucus simply means your immune system is actively fighting something. White blood cells release enzymes that tint the mucus as they break down, and that happens with viral infections, too. So while thick, discolored discharge is one piece of the puzzle, it’s not reliable enough on its own to confirm bacteria are involved or that you need antibiotics.
When It Becomes Chronic
Acute sinus infections last less than 12 weeks and usually resolve much faster, within two to four weeks. If your symptoms persist for 12 weeks or longer, even at a low level, the condition is reclassified as chronic sinusitis. Chronic sinusitis involves the same core symptoms (congestion, discharge, facial pressure, reduced smell) but tends to be less intense and more grinding. It often has different underlying causes, like nasal polyps, structural issues, or ongoing inflammation rather than a single bacterial infection. Chronic sinusitis requires a different treatment approach and typically needs evaluation by a specialist.
Symptoms That Need Immediate Attention
Sinus infections can, in rare cases, spread to nearby structures like the eye sockets or the lining of the brain. Certain symptoms signal this is happening and require emergency care:
- Swelling or redness around one or both eyes
- Double vision or other changes in your eyesight
- High fever that doesn’t respond to typical treatment
- A stiff neck
- Confusion or altered mental state
These are uncommon, but they represent infections that have moved beyond the sinuses into dangerous territory. Pain and pressure around the eyes during a normal sinus infection is expected. Visible swelling, redness, or vision changes are not.
Putting It All Together
The simplest way to self-assess: count your symptoms and watch the calendar. If you have at least two of the core four symptoms (congestion, thick discharge, facial pain/pressure, reduced smell) and they’ve lasted more than ten days without improving, or they got better and then worse again, you’re most likely dealing with a sinus infection rather than a lingering cold. If the symptoms are under ten days and gradually improving, your body is probably handling a viral infection on its own, and it will likely resolve without treatment.