To get lasting sinus pressure relief, you need to get at the root cause of the infection. Relieving sinus pressure with over-the-counter products only deals with the symptoms; this treatment won't do anything to cure the underlying condition.

Causes of Sinusitis
Severe sinus pressure is known as sinusitis. It can be caused by a fungal, viral or bacterial infection. 

The infection causes the nasal passages to become inflamed and irritated. The symptoms of sinusitis are headaches, excess mucus and facial pain located behind the eyes or a tight feeling across the face. A runny nose often accompanies sinus pressure, because inflamed sinus passages produce extra mucous to flush out the irritation.  

Sinusitis can be caused by a cold or the flu. In this case, the symptoms will clear up once your body fights off the infection.

If you have sinusitis on certain days or at certain times of the year, allergies are likely to blame. Make an appointment with an allergist to determine the source of your allergies and to get a treatment program to manage symptoms.

Ongoing sinusitis, or sinusitis that lasts long after a cold or allergy season has passed, could be the result of a fungal infection or a virus. See your doctor if sinusitis is chronic or persistent. Antibiotics may be all that's needed to provide lasting relief.

Minimizing Sinus Pressure
When sinusitis hits, use these tips to get temporary relief.

Moisture
If your nose is running, the last thing you think you need is more moisture, even though you do. Keeping your nasal passages moist helps flush out the irritants.

To keep your nasal passages moist, use a humidifier or vaporizer. Both put extra moisture in the air, preventing your sinuses from drying out. Hot steam from either the shower or a steam pot is also beneficial. To use a steam pot, place a pot of boiling water on the counter, drape a towel over your head, and lean over the steam and breathe deeply. Be very careful not to lean too close to the water.

Increase your fluid intake by drinking water or juice. This thins out the mucus and may prevent your sinuses from getting blocked. You can also try an over-the-counter saline spray or make your own by mixing a small amount of salt with water.

Irrigation
Irrigation uses salt water to flush all the mucus, allergens and germs out of your sinuses.  To irrigate your sinuses, use a bulb syringe, Neti pot or nasal irrigator.

Supplements
Speak to your doctor about adding supplements to your diet. Some herbs, such as Indian Echinacea, may help alleviate cold symptoms and reduce sinus pressure.

Over the Counter Medicine
A decongestant will reduce the swelling in the nasal passages. Decongestants come in oral form and nasal sprays. Do not use a nasal spray for more then three days and do not use oral decongestants for more than seven days. Decongestants are not recommended for young children.

Antihistamines reduce your body's reaction to allergy-causing substances, such as pollen. This can help to relieve minor sinus pressure.  Over-the-counter pain medication will do nothing to clear up stuffiness, but it will minimize sinus pain and headaches.

Other remedies to try include placing a warm, not hot, compress on your face; sleeping upright by propping yourself up with a couple of extra pillows and using heated herbal eye masks.