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.
Sinusitis is inflammation and swelling of the lining membranes of the sinuses. This is commonly caused by bacterial or viral infections or blockage of the sinus openings by thickened mucosa called polyps. Symptoms of sinusitis include facial pain or pressure, nasal obstruction, discolored nasal drainage, loss of sense of smell, and headaches. The majority of patients with sinusitis can successfully be treated with antibiotics or other medications, treatment of allergies or environmental control.