[Xerostomia in palliative care]

Xerostomia is the subjective feeling of mouth dryness, caused or not by function lowering of salivary glands, with decrease of saliva quality or quantity. It's a frequent symptom in palliative care patients and its prevalence is referred to be 60% to 88% in advanced and progressive oncological disease patients. Xerostomia has physical, social and psychological consequences. Saliva plays an important role in maintaining the best physiological conditions of mouth. Besides humidifying the oral cavity tissues, its lubricating properties help swallowing, talking and prevents other damages caused by mechanical and noxious microbiological agents. Xerostomia is caused by three basic mechanisms: factors that compromise the salivary centre, factors related to the autonomic stimulation or factors related to salivary glands themselves. The diagnosis is mainly clinical. Mouth condition must be thoroughly evaluated. If justified, a quantitative evaluation of saliva secretion, in rest and under stimulation, might be done. The treatment must be oriented by aetiology and directed towards the disease effects in patient comfort and quality of life. During treatment, the use of xerogenic drugs should be controlled, hydration should be promoted and other symptom control measures improved. The symptomatic treatment has three pathways: the increasing of saliva production by mechanical, gustatory or pharmacological stimulation; the using of saliva substitutes and the improving of active mouth care. Mechanical stimulation is obtained by chewing gum and gustatory stimulation may be reached by sucking Vitamin C tablets. Pilocarpine is the available drug to improve salivation. A soft diet must be advised, hard and dry food, tobacco and alcoholic beverages should be avoided. It's important that health workers teach patients with xerostomia the best way to get relief and the measures to prevent its complications that could, even more, compromise their quality of life.