Enzymes to the Rescue|
Oral enzyme supplements have been used to treat sinusitis for more than 30 years. As early as 1966, S.J. Taub, M.D., found that bromelain, an enzyme from pineapple that breaks up proteins, produced marked changes in patients suffering from both acute and chronic sinusitis.  Bromelain effectively thinned nasal secretions and reduced swelling and redness of the nasal mucosa. A study in 1967 corroborated Taub's findings, showing that bromelain could help clear the mucus associated with sinusitis, stimulate immune function and reduce headaches. 
Another study using the enzyme combination of bromelain, chymotrypsin, pancreatin, papain and trypsin plus the bioflavonoid rutin showed that these enzymes were as effective as diclofenac (a nonsteroidal anti-inflammatory often recommended for sinusitis) at reducing headache and toothache pain, as well as the sensation of pressure, without side effects.  In the study, 40 patients with acute sinusitis were matched with respect to sex, age, weight, height, pus, swelling of the middle meatus of the nose, fever, toothache in the upper jaw, sensation of pressure, ultrasonic findings and headache.
One group received one teaspoon of a granulated compound containing bromelain, papain, pancreatin, trypsin and chymotrypsin plus the bioflavonoid rutin, and two placebo capsules twice daily. The control group received one teaspoon of a granulated placebo twice daily and two capsules of diclofenac. After 14 days, researchers concluded that the treatments brought similar results but no side effects for the enzyme group.
Proteolytic (protein-breaking) enzymes such as bromelain are used most frequently to treat sinusitis. Research shows that proteolytic enzymes decrease the thickness of the respiratory mucus,  thus reducing the pressure on the sinuses and easing breathing. They also are anti-inflammatory and reduce pain and swelling. Enzymes stimulate the immune system, which helps the body fight infection. 
Advise customers with sinusitis to take enzyme supplements between meals.
Anthony Cichoke, M.A., D.C., D.A.C.B.N., a lecturer and researcher, is author of numerous books and articles on enzyme therapy.
The use of ananase in sinusitis. A study of 60 patients.
The Eye, Ear, Nose and Throat Monthly 1966;45:96,98.
A double-blind clinical evaluation of bromelain in the treatment of acute sinusitis.
Enzymkombinationspräparat zur therapie der sinusitis acuta.
Der Allgemeinarzt 1993;15:104-14.
Gardner MLG, Steffen KJ, editors.
Absorption of orally administered enzymes.
Berlin: Springer-Verlag; 1995.