Allergies, Cold or Sinus Infection? How To Tell

Every spring, as pollen fills the air, millions of people worldwide seek relief from sneezing, coughing and nasal congestion. If you’re one of them, you may wonder if you have a cold, an allergy or a sinus infection.

Fever and itchy eyes are important clues to identify the cause of your symptoms: Colds and the flu are caused by viral infections, and your body’s response typically includes fever. An allergic reaction alone never causes fever, but it may well produce itchy, watery eyes.

The timeline is also a clue: Allergy symptoms appear quickly after exposure to the allergen, while colds tend to come on more slowly, with mild symptoms at first. And allergy symptoms may last several weeks or be recurrent, while a cold typically clears in seven to 10 days.

If you have a recurring respiratory allergy, treatments are available to desensitize you over time to the allergen to reduce the frequency of attacks. But in the short term, there is no medical cure for a viral infection or an allergic reaction. The best you can do is mitigate the symptoms while waiting for the pollen to settle or your body to defeat the virus.

If your symptoms get worse, you may have a bacterial sinus infection, which requires medical treatment.

Immune Response

Whenever you breathe through your nose, the air passes through cavities on both sides of your face and behind your forehead, called paranasal sinuses, where it is warmed and humidified before reaching the lungs.

Both the nose and the sinuses secrete a thin mucus membrane that catches contaminants, preventing them from reaching your lungs. If the contaminant is non-threatening, your body clears it naturally when mucus drains down the back of the throat and into the stomach or when you cough, sneeze or blow your nose.

But if your body identifies the contaminant as something dangerous -- like a virus or bacteria -- a complex immune response is triggered, flooding the bloodstream with chemicals called histamines that quickly lead to inflammation of the affected tissues. This immune response also occurs when the body misidentifies a benign invader as something dangerous.

Whether the danger is real or not, the result is sinusitis, the medical term for inflamed sinuses and one of the most common reasons for doctor’s office visits in the United States. You may experience this inflammation through one or more of these common symptoms:

• Runny nose
• Sore throat
• Cough
• Fever
• Fatigue
• Muscle aches
• Joint pain
• Swollen lymph nodes

Temporary sinusitis typically lasts less than four weeks. It is considered chronic when it recurs frequently or symptoms last longer.

Secondary Infections

The timeline is important when dealing with sinusitis. That’s because while you’re waiting for your allergy or cold to pass, a more serious problem could be developing. You have naturally occuring bacteria in your respiratory track, and all that excess mucus produced during sinusitis creates an ideal environment for them to multiply, causing a secondary infection.

You may suspect a bacterial sinus infection if your symptoms persist or worsen about 10 days after onset, especially when accompanied by fever and greenish nasal discharge. If you are recovering from a cold, your cough or sore throat will probably have resolved, but other possible symptoms of a sinus infection include:

• Postnasal drip
• Severe headaches
• Facial tenderness or pain
• Pain in the teeth
• Bad breath

Diagnosis and Treatment

See your health care provider if you have any of those symptoms or worsening symptoms after a period of improvement.

To avoid unnecessary use of antibiotics, your doctor may recommend waiting a few days to see if you need antibiotics, or they could prescribe an antibiotic but suggest you wait a few days before filling the prescription to see if you recover on your own. Both are strategies to avoid overuse of antibiotics, which will not help (and can hurt) if you do not have a bacterial infection.

Once you are healthy again, you can reduce the chances of further sinus infections with heathy practices like these:

• Wash your hands frequently
• Receive all recommended vaccinations
• Avoid close contact with sick people
• Avoid dry environments; use a humidifier to moisten air
• Use a saline sinus wash to flush clogged nasal passages
• Don’t smoke and avoid other nasal irritants
• Use decongestants with caution to avoid a rebound effect