The hallmark signs of a sinus infection are thick yellow or green nasal discharge, facial pressure that worsens when you bend forward, and congestion that makes it hard to breathe through your nose. If those symptoms have lasted more than 10 days without improving, or they seemed to get better and then got worse again, you’re likely dealing with a sinus infection rather than a regular cold.
The Core Symptoms
Sinus infections produce a recognizable cluster of symptoms. The most common are pain, tenderness, and pressure around your forehead, cheeks, and eyes, along with a stuffy nose and thick, discolored mucus draining from your nose or down the back of your throat. That postnasal drip often triggers a cough, especially at night, and can leave a bad taste in your mouth.
You might also notice bad breath, fatigue, and a mild fever. One symptom that surprises many people: pain in your upper back teeth. The largest sinus cavities sit directly above the roots of your upper molars, so when those sinuses swell, the pressure can feel exactly like a toothache. If you have upper tooth pain alongside nasal congestion, your sinuses are the likely culprit, not a cavity.
A reduced sense of smell is another telltale sign. Swelling inside the nasal passages blocks the receptors responsible for detecting odors, so food may taste bland and familiar scents may disappear entirely.
A Simple Self-Check for Sinus Tenderness
You can check for sinus tenderness at home with your thumbs. Using gentle circular pressure, press just below each eyebrow along the bony ridge above your eyes (avoiding the eye socket itself). Then press on either side of your nose, just below the cheekbones. A little pressure is normal. If either spot feels distinctly painful or tender, your sinuses are inflamed.
This won’t diagnose you, but it gives you useful information. Tenderness in those specific spots, combined with the symptoms above, paints a clear picture.
Cold, Allergies, or Sinus Infection
These three conditions overlap enough to cause real confusion, but each has distinguishing features.
A cold develops over a few days, usually starts with a sore throat, and clears up within about a week. You may have a low fever, body aches, and a runny nose, but the discharge is typically clear or slightly white, and you steadily improve after the first few days.
Allergies start shortly after exposure to a trigger and last as long as the exposure continues. The giveaway is itching: itchy, watery eyes and an itchy nose point strongly toward allergies rather than an infection. Allergies also never cause a fever.
A sinus infection produces thicker, colored mucus (yellow or green), facial pressure and pain, and symptoms that persist well beyond the one to two week window of a typical cold. A mild fever is possible but not always present. The duration and the quality of the discharge are your most reliable clues.
When It’s Viral vs. Bacterial
Here’s something most people don’t realize: the vast majority of sinus infections start as viral infections, meaning antibiotics won’t help. A viral sinus infection looks and feels much like a bad cold that settles into your sinuses, and it resolves on its own.
Three patterns suggest the infection has become bacterial and may need treatment:
- Persistent symptoms: Congestion, facial pain, and discolored drainage lasting at least 10 days with no improvement.
- Severe onset: A fever of 102°F or higher along with facial pain and nasal discharge lasting three to four consecutive days.
- Double sickening: You start to feel better after four to seven days, then your symptoms return and get worse. This rebound pattern is a strong indicator of a bacterial infection.
Even bacterial sinus infections can resolve without antibiotics. Current guidelines support a period of watchful waiting for otherwise healthy adults, with symptom management (saline rinses, decongestants, pain relievers) as the first approach. If symptoms don’t improve after several more days, that’s when antibiotics enter the picture.
How It Shows Up Differently in Children
Kids get sinus infections too, but their symptoms can look different depending on age. Younger children typically present with a runny nose that lasts longer than seven to ten days, a persistent cough, and sometimes a fever. The nasal discharge is usually thick and green or yellow, though it can also be clear, which makes it easy to mistake for a lingering cold.
Older children and teens look more like adults: headaches, facial pain, postnasal drip, and congestion that won’t quit. The key distinction at any age is duration. A cold that refuses to improve after 10 days, or one that rebounds after initial improvement, points toward a sinus infection.
Acute vs. Chronic Sinusitis
Acute sinusitis lasts less than four weeks and is what most people mean when they say “sinus infection.” Chronic sinusitis is a different condition altogether, defined by at least 12 consecutive weeks of symptoms. To meet the diagnostic criteria, you need at least two of these four: facial pain or pressure, reduced or lost sense of smell, nasal drainage, and nasal obstruction.
Chronic sinusitis isn’t just a sinus infection that never went away. It often involves persistent inflammation driven by structural issues, nasal polyps, or allergies rather than an active infection. If your symptoms cycle on and off for months, or if you feel like you always have a sinus problem, that distinction matters because the treatment approach is different.
Symptoms That Need Immediate Attention
Sinus infections very rarely become dangerous, but the sinuses sit close to the eyes and brain, so complications can be serious when they occur. Get emergency care if you develop sharp eye pain, blurry vision, a bulging or swollen-shut eye, limited ability to move your eyes, a severe headache unlike your usual sinus pressure, a high fever, or a stiff neck. These can signal that the infection has spread beyond the sinuses into the eye socket or toward the brain, and they require urgent treatment.