Sinusitis is caused by too much mucus, or a swelling of the lining of
the sinuses, which can block the narrow drainage channels. It's usually the
result of a cold or flu virus, an allergy or irritant that causes the
membranes of the sinuses to become inflamed. Because of this,
preventing colds and the flus is one of the best ways to prevent sinusitis.
A decongestant such as Otrivin® can help
unblock your nose.