The hallmark symptoms of a sinus infection are thick, discolored nasal discharge combined with facial pressure or pain, nasal congestion, and a reduced sense of smell. Most sinus infections start as a common cold, so the early days can feel identical. The key difference is what happens after day five: cold symptoms improve, while a sinus infection lingers or gets worse.
The Core Symptoms
Sinus infections produce a recognizable cluster of symptoms that center on the nose and face. Nasal congestion is usually the most noticeable, making it difficult to breathe through one or both nostrils. Alongside that congestion, you’ll typically have thick nasal discharge that drips from the nose or runs down the back of the throat (a sensation often described as postnasal drip, which triggers frequent throat clearing or a persistent cough).
Facial pain and pressure tend to concentrate in specific zones depending on which sinuses are inflamed. The maxillary sinuses sit behind your cheekbones, so infection there creates aching pressure across the mid-face. The frontal sinuses above the eyebrows produce forehead pain, while the ethmoid sinuses between the eyes cause a deep bridge-of-the-nose pressure. This pain often intensifies when you bend forward or lie down.
A diminished or completely lost sense of smell is common during a sinus infection. Because taste relies heavily on smell, food may seem bland or off. This usually resolves once the congestion clears.
Symptoms Beyond the Sinuses
A sinus infection doesn’t just affect your nose and face. Fatigue, weakness, and a general run-down feeling are typical, even when the infection itself is relatively mild. Your body is directing energy toward fighting infection, which leaves less for everything else. Low-grade fever can accompany acute sinus infections, though high fever is uncommon and may signal something more serious.
Coughing is another frequent complaint, particularly at night. Postnasal drip irritates the throat when you lie flat, which can disrupt sleep and worsen fatigue during the day. Bad breath is also surprisingly common with sinus infections because bacteria-laden mucus drains into the back of the throat.
Tooth Pain and Other Unexpected Signs
One symptom that catches many people off guard is upper tooth pain. The maxillary sinuses sit directly above the roots of your upper back teeth. When those sinuses swell, pressure pushes down on the tooth roots, creating aching or sensitivity across several upper teeth at once. A telling clue: the pain gets worse when you bend over or change head position. Some people’s dental roots actually extend into the sinus cavity, which makes this crossover pain even more pronounced.
Ear fullness or mild ear pressure can also develop, since the sinuses, nasal passages, and ears share connected drainage pathways. And because postnasal drip constantly coats the throat, a sore or scratchy throat is common even without a separate throat infection.
Cold vs. Sinus Infection: How to Tell
Since most sinus infections begin as colds, the real question is when a cold crosses the line. There are two reliable patterns to watch for.
The first is simple persistence. Cold symptoms typically start improving after three to five days. If your congestion, facial pressure, and discolored discharge last longer than 10 days without any improvement, that pattern points toward a bacterial sinus infection rather than a lingering cold.
The second pattern is called “double worsening.” You start feeling better after the first few days, then suddenly get worse again, with renewed facial pain, thicker discharge, or returning fever. That rebound suggests what started as a viral cold has progressed into a bacterial sinus infection. Both of these patterns are the primary markers doctors use to distinguish a bacterial infection from a viral one.
Mucus color alone isn’t a reliable indicator. White, yellow, and green discharge all occur with ordinary colds. Thick yellow or green mucus combined with the timing patterns above is more meaningful than color by itself.
How Symptoms Differ in Children
Children get sinus infections frequently, but they don’t always describe symptoms the way adults do. Instead of reporting facial pressure, a child with a sinus infection often shows irritability, behavioral changes, or general fussiness. A cough that’s worse at night is one of the most consistent signs in kids, driven by the same postnasal drip that bothers adults.
Other signs to look for include persistent bad breath (not explained by dental hygiene), facial swelling, headache, and a runny or stuffy nose with symptoms that worsen around the 7 to 10 day mark. Fever may or may not be present. Because younger children can’t blow their noses effectively, congestion tends to be more disruptive to eating and sleeping.
Acute vs. Chronic: The Timeline Matters
Acute sinus infections last up to four weeks. This is the most common type, and the vast majority resolve on their own or with treatment during that window. If symptoms persist beyond four weeks but clear up before 12 weeks, the infection is considered subacute.
Chronic sinusitis is defined by symptoms lasting 12 weeks or longer. The symptoms are the same, congestion, facial pressure, discolored drainage, reduced smell, but they’re generally milder and more grinding than the acute version. People with chronic sinusitis often describe a baseline of dull facial pressure, perpetual stuffiness, and fatigue that flares periodically rather than arriving all at once.
Red Flag Symptoms That Need Immediate Attention
Most sinus infections are uncomfortable but not dangerous. A small number, however, can spread to nearby structures like the eye socket or the lining of the brain. Seek care immediately if you develop any of the following alongside sinus symptoms:
- Pain, swelling, or redness around the eyes
- Double vision or other sudden vision changes
- High fever
- Confusion or difficulty thinking clearly
- A stiff neck
These signs suggest the infection may be spreading beyond the sinuses and requires prompt evaluation. This is rare, but recognizing these symptoms early makes a significant difference in outcomes.