There are many causes of dry mouth. Dry mouth most commonly occurs as a side effect of medications that cause decreased saliva production, including high blood pressure medications, antihistamines, antidepressants, diuretics, nonsteroidal anti-inflammatories, narcotics, and many others.
Liquid diet: The Liquid diet is the restriction of solid food intake, and replacement of solid food with liquids. In hospitals, liquid diets are prescribed by doctors for a number of reasons for patients who are unable to consume solid foods. Liquid diets may be prescribed following surgery or as a preparation for certain medical procedures.
A liquid diet usually results in quick weight loss, because you restrict calories severely when you cut out whole foods. Weight loss occurs when you eat fewer calories than you burn; you lose a pound when that deficit reaches 3,500 calories. The average person needs about 2,000 calories to maintain body weight.