What Is the Cause of Sinus Infection?

You wake up with a congested nose, a lingering dry cough and a headache that over-the-counter pain relievers cannot touch. You might also find yourself coughing constantly, especially when you lie down to rest at night. If this sounds familiar, your sinuses are likely the culprit.

What are sinuses? 

Your sinuses are four pairs of air-filled cavities located behind your forehead, cheeks and eyes. They are lined with cells that secrete mucus to keep your nasal passageways working properly. However, when the small air passages into the sinuses become blocked, air cannot get in and mucus cannot get out. Germs may then build up in that blocked fluid, causing a sinus infection, also called sinusitis.

Why do you get sinus infections?

The primary causes of sinus infections are viruses. Bacteria may complicate sinus infections in a small number of cases. Other factors, such as a history of asthma, allergies to pollen, dust, mold, fungi, pet dander, pollutants or exposure to secondhand smoke, can trigger sinus inflammations. 

How do I know if my sinus is infected?

You may notice a feeling of fullness or pressure in your face, often behind your cheeks or around your eyes. Many people also experience postnasal drip, where excess mucus drains down the back of the throat. This can irritate the throat and contribute to a cough that may worsen when lying down at night. Paying attention to how your head and respiratory system feels on a regular basis can help identify symptoms of a sinus infection. When your sinuses are healthy, a thin layer of mucus is continuously swept out through small openings by structures in your upper respiratory tract. During a sinus infection, swelling blocks these openings and this system does not work as well. At the same time, your body produces a larger amount of mucus as well as thicker mucus. This results in the buildup of mucus in the sinuses that can cause pressure and pain.

Unlike a brief allergy flare-up, a sinus infection lingers. Acute sinusitis may occur suddenly and may last a few days up to a period of several weeks. Chronic sinusitis continues for at least three months and may require more structured treatment approaches to resolve.

What are the four main symptoms of sinusitis?

While sinusitis presents with variety of uncomfortable signs, the most common symptoms are:

• Thick, cloudy or discolored nasal discharge
• Nasal congestion or stuffiness
• Facial pain, pressure, or fullness (usually around the cheeks, eyes or forehead)

You also might notice secondary symptoms such as cough, sore throat, reduced sense of smell, headache, fatigue, ear fullness, bad breath and fever. 

What can be mistaken for a sinus infection?

Several conditions can be confused with a sinus infection. The common cold is the most frequent imposter, since it involves the sinuses in most cases. The symptoms of a common cold and bacterial sinus infection overlap significantly, but a bacterial infection is more likely when symptoms last longer than 10 days without improving, get worse after starting to get better, or begin with a high fever and thick, discolored nasal discharge.

Allergies can also closely mimic sinusitis caused by an infection. Seasonal or environmental allergens may also cause a runny nose, sneezing and congestion. However, allergies are usually accompanied by itchy, watery eyes and lack the thick, discolored mucus associated with a bacterial sinus infection.

Finally, certain viral infections like COVID-19 or the flu can look similar in their early stages. If you experience a sudden high fever or severe body aches, you may be dealing with a virus causing a sinus infection.

How do you cure sinus infection fast?

You can use several strategies to clear up congestion and relieve pressure quickly. Some of the most common remedies are:

• Over-the-counter medications: You can treat nasal and sinus congestion with over-the-counter decongestant once or twice a day. If you have high blood pressure, avoid certain decongestants and consider using other treatment options such as nasal saline. 
• Treat postnasal drip: Use an antihistamine to dry up postnasal drip. This directly helps control the cough that keeps you awake at night.
• Flushing the sinuses: A Neti Pot (or any nasal saline rinse) helps flush your sinuses of mucus buildup and trapped allergens. You can use this multiple times a day. Always use distilled water, never tap water.
• Steam and moisture: Breathe hot steam through your nose for 10 to 15 minutes, three to four times a day. Place a cool mist humidifier in your bedroom to moisturize your nasal passages while you sleep.
• Dietary adjustments: Dairy products increase mucus production. Restricting milk and dairy from your diet temporarily can help reduce congestion.
• Staying well hydrated: Maintaining adequate hydration can help your body to fight off the infection.

If your sinus infection is severe, consult your healthcare provider on the best treatment options, including whether antibiotics or other interventions are necessary.

Do sinus infections go away?

Yes, most sinus infections go away on their own. Your body’s immune system can fight off most mild viral and bacterial diseases. In fact, most sinus infections clear up entirely without the need for antibiotics within 10 days.

To help the infection run its course quickly, you should prioritize bed rest and increase your daily fluid intake. Applying warm compresses to your face also relieves sinus pressure while your body heals. If your symptoms show steady improvement over a week, your immune system is successfully managing the infection.

Can I clear up sinus infections without antibiotics?

You absolutely can clear up a sinus infection without antibiotics. Many people mistakenly believe that every sinus infection requires a prescription antibiotic. Because viruses cause the majority of sinus infections, antibiotics, which only treat bacterial infections, often provide no benefit.

Using antibiotics when they are not necessary can lead to negative consequences, and these risks are not worth taking when antibiotics will not help. The most common side effects are gastrointestinal problems such as nausea, diarrhea and stomach pain. Less common reactions can include severe allergic responses, such as severe skin rashes, and a dangerous gastrointestinal infection called C. difficile. Additionally, the development of antibiotic-resistant bacteria increases with inappropriate antibiotic usage since bacteria can change and stop responding to the medications that are designed to kill them. Therefore, physicians and other healthcare providers often recommend a "watchful waiting" strategy, which involves monitoring your symptoms for a few days while using home remedies, bed rest and over-the-counter pain relievers.

However, you should see a physician or healthcare professional if you begin to experience severe facial pain, symptoms that worsen after initially improving, symptoms lasting longer than 10 days with no relief or a fever that lasts more than three to four days. In these specific cases, a healthcare professional can determine if antibiotics are the appropriate course of action in addition to other remedies.

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