Do you mean mucus?   It's a myth that drinking milk or consuming milk products produces or worsens mucus.   Symptoms of food allergies (including milk/dairy allergy) include: scratchy throat abdominal pain diarrhea nausea vomiting stomach cramps itching of the mouth, throat, eyes, skin, or any area hives swelling, especially of the eyelids, face, lips, and tongue light-headedness or fainting nasal congestion runny nose shortness of breath wheezing difficulty swallowing You should see your doctor about the increased mucus and sinus draining issue you are having. In the mean time, you can try avoiding milk and foods that contain milk to see if that helps your symptoms. Click here to find a list of foods that may contain milk (also, be careful about foods that may contain butter).