Hello XXXXXXX,

Thanks for your query.

Sinusitis is the inflammation/infection of the paranasal sinuses.
When it spreads to the sinus opening, it causes blockage & interferes with the normal ventilation and pressure equalization of the sinuses.

The reason of concern in this situation is presence of air inside the sinuses due to closure of the sinus opening.
This entrapped air tends to expand due to change in pressure during air travel (especially during the phase of descent) resulting in severe pain & sometimes bleeding from the nose.
This condition is known as Sinus Barotrauma.

Though the symptoms of Sinus Barotrauma can be felt even on ascent, one has to be extremely careful during descent.
During this phase, the pressure in the surrounding atmosphere increases as compared to that inside the sinuses.
This difference in pressure causes expansion of the air inside the sinus, which cannot escape out due to the blocked opening.
Hence causes all the symptoms.

If an air flight has to be made, then certain preventive measures can be taken like:
1. Chewing gum (helps in equalization of pressure)
2. Administration of nasal drops (it reduces the swelling & inflammation and helps to maintain patency of the sinus opening)
3. Pain killers(for symptomatic relief)
4. Antibiotics & Phenylpropanolamine preparation as already advised by your treating physician.

However, for safety purpose, it is always advised to avoid air flight till the symptoms of sinusitis completely subside.

Wishing you a Good Health.
Let me know if I need to clarify further.
Thanks & take care.

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