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 helps provide sufficient hydration, helps maintain electrolyte balance, and is often prescribed for people when solid food diets are not recommended, such as for people who suffer with gastrointestinal illness or damage, or before or after certain types of medical tests or surgeries involving the mouth or the digestive tract.