Drink more fluids. Water helps loosen mucus and soothe an irritated throat. Dry, hacking coughs respond to honey in hot water, tea, or lemon juice. Do not give honey to children younger than 1 year of age. Elevate your head with extra pillows at night to ease a dry cough. Try a cough drop to soothe an irritated throat.
That is actually true to a certain extent. Most of the time you need to have some sort of sensitivity/allergy to dairy. But dairy products can increase the thickness of your phlegm, therefore can clog up your sinuses, and eventually cause the sinus pressure.
Causes of sinusitis. Sinusitis is caused by too much mucus, or a swelling of the lining of the sinuses and nose, which can block the narrow channels. This can occur during a cold, or may be due to allergy (for example, hayfever) or irritation of the linings of the sinuses (for example, from chlorine in a swimming pool).