Infectious rhinitis can be caused by a virus. Non-infectious rhinitis can be caused by pregnancy or a thyroid disorder. Occupational rhinitis can be caused by things in your work environment. Drug-induced rhinitis can be caused by blood pressure medications, oral contraceptives, overuse of nasal decongestants, and illicit drugs like cocaine. Food-induced rhinitis can be caused by food allergies, and dilation of blood vessels in the nose.
Nasal polyps can also cause a runny nose.
Spicy foods and alcohol dilate blood vessels in the lining of the nose, and can cause a runny nose. An allergy to a certain food may cause a runny nose. A doctor may do tests if a particular kind of food seems to cause a runny nose, especially if the runny nose is accompanied by other symptoms like lip and face swelling, rash, or wheezing and trouble breathing. Your husband should see his doctor about his runny nose. His doctor may refer him to an allergist for testing.