Excessive and repeated use of nasal decongestants leads to severe sinus congestion.  The sinus membranes are damaged so badly that they cannot be repaired. Thus, never use the medicine without prescription by a qualified medical expert.

Apnea means an end of airflow for less than ten seconds, hampering oxygenation, ventilation and respiration. Obstructive sleep apnea (OSA) is a chronic medical condition in which apnea occurs even when the respiratory muscle is trying to breathe because of an obstruction within the upper respiratory tract. The principal source of blockage is the tongue. Other obstructions include blood and foreign bodies. These obstructions block the airways. The OSA causes a number of problems including sinus congestion, headaches due to weight gain, depression, inattentiveness and sleepiness in daytime. Even alcohol- and drug-induced severe sinus congestion may worsen OSA in the patients with sensitive immune system.

Flu (influenza), a viral infection, may infect the sinuses and cause sinus congestion. After partial recovery from flu, some patients again feel sick as secondary bacterial infections may appear. The infections, such as bronchitis, ear infections or bacterial sinusitis, lead to the congestion.

Visit a doctor to find the real cause of the congestion. Do not ignore sinus congestion because it could be painful and could interfere with day-to-day life. For instance,

If you are suffering from sinus congestion and the infections of the upper respiratory tract, you should not dive.

Severe congestion impairs the sense of smell and taste.

Extreme sinus congestion spreading to the ears causes vertigo.

Severe congestion may be indicative of asthma.