Take anti histamines for allergies to grass hayfever, avoid smoking, it causes catarrh your pharmacy will have more advice too
What Causes Sinus Congestion?
Many things can cause sinus congestion. Allergies and hayfever, infections, and simple dehydration.
from www.emedicinehealth.com
Acute sinusitis usually follows a viral infection in the upper respiratory tract, but allergy-causing substances (allergens) or pollutants may also trigger acute sinusitis. Viral infection damages the cells of the sinus lining, leading to inflammation. The lining thickens, obstructing the nasal passage. This passage connects to the sinuses. The obstruction disrupts the process that removes bacteria normally present in the nasal passages, and the bacteria begin to multiply and invade the lining of the sinus. This causes the symptoms of sinus infection. Allergens and pollutants produce a similar effect.
from www.emedicinehealth.com
Sinus Infection Causes
Acute sinusitis usually follows a viral infection in the upper respiratory tract, but allergy-causing substances (allergens) or pollutants may also trigger acute sinusitis. Viral infection damages the cells of the sinus lining, leading to inflammation. The lining thickens, obstructing the nasal passage. This passage connects to the sinuses. The obstruction disrupts the process that removes bacteria normally present in the nasal passages, and the bacteria begin to multiply and invade the lining of the sinus. This causes the symptoms of sinus infection. Allergens and pollutants produce a similar effect.