Was wondering what illesses cause an overactive salivary gland?

Many things: Overactive salivary glands are usually nothing to worry about. Salavia is produced depending on your diet, spicy and acidic foods will increase production. So the first thing to do is change your diet. Some medications as well as some medical cinditions can cause an increase in salvia. Some conditions that can cause this are gerd, infections, , allergies, stroke, pregnancy, bell's palsy , more.