from the teeth and gums preventing dental caries, gum disease and overgrowth of microorganisms. Dental caries is another term for tooth decay or cavities, which is typically caused by erosion of tooth enamel by acid.

consumption of sugar-containing foods and drinks in an attempt to stimulate salivary flow. Dental complications can lead to permanent tooth loss or the need for surgical intervention. Overgrowth of the fungus Candida albicans can lead to candidiasis or oral thrush. This is the most commonly observed oral infection associated with dry mouth and may appear as a white curd-like coating of the tongue, cheek or palate. Left untreated, candidiasis can cause extreme pain and discomfort, resulting in further loss of appetite and possible weight loss.

PATIENT SCENARIO 1

SYMPTOMS

The common signs and symptoms of dry mouth are listed in Table 1. ^{2, 5-7}

Dry mouth is a subjective complaint, but initially a decrease in saliva production will result in complaints of a dry, sore and burning mouth. This will require a frequent need to sip or drink water when talking and eating, especially with dry foods. Further reduction in saliva will result in changes to the oral mucosa. The tongue may appear fissured, pallor of oral tissues and cracks at the corners of the mouth. Although some people remain asymptomatic, the consequences of dry mouth on the oral cavity may still be observed during a dental examination. Unfortunately dental caries may not present with early symptoms of dry mouth and may not be detected until substantial tooth erosion has taken place. For these reasons, educating at-risk populations about preventive care with appropriate oral hygiene is essential. Such systemic symptoms as nasal and ocular dryness, decreased sense of smell, acid reflux, dry cough, fatigue and weight loss may co-exist with dry mouth. ⁸

Patient case

Mrs. Simpson is 55 years old and a regular customer of your pharmacy. She was diagnosed with hypertension six months ago when she was started on hydrochlorothiazide. Last month she was started on an additional medication, Toprol XL. You realize that Mrs. Simpson is one week late in refilling her antihypertensive medications. After contacting the patient, you are told that she has been experiencing some side effects since starting her new medication. Upon further questioning you find out that she feels the need to frequently sip water when eating and talking, and has a sticky and dry feeling in her mouth. These side effects have become so bothersome that she would rather not take the Toprol XL. How do you handle this situation?

RISK FACTORS

Medications, Sjögren’s syndrome, head and neck radiation therapy and other systemic diseases are common risk factors for dry mouth. Table 2 lists the most common medication classes associated with dry mouth. ^{3, 4, 9} It is estimated that there are more than 42 drug categories that contain xerogenic drugs. ² Nonprescription decongestants, antihistamines and antidiarrheals are additional culprits of causing dry mouth. Medications tend to affect the quantity and/or quality of saliva. However these side effects are reversible, and salivary function returns to normal upon discontinuation of the medication.

Sjögren’s syndrome, a chronic autoimmune condition, is the most common disease state associated with causing dry mouth, as well as dry eye. Sjögren’s syndrome causes infiltration of lymphocytes in the salivary and lacrimal glands. ¹⁰ This causes gradual destruction of the secretory mechanisms of the salivary glands and decreased nerve stimuli to the glands. ⁴ Patients with daily dry mouth for more than three months, ocular symptoms and frequent need to use liquids to assist in swallowing foods should seek medical follow-up to rule out Sjögren’s syndrome. ¹¹

Radiation therapy of the head and neck can cause injury to the salivary glands resulting in temporary or permanent dry mouth. Other conditions found to increase an individual’s risk of dry mouth include HIV-infection, uncontrolled diabetes, rheumatoid arthritis, hypertension, stress, anxiety, bone marrow transplant and thyroid dysfunction. Although diabetes is not directly associated with dry mouth, it can increase the risk of dental complications, especially in those who are not well-controlled. An individual with

Discussion

The symptoms described by this patient correlate with dry mouth, most likely caused by her new medication. Toprol XL is a beta-blocker, a class known to increase the risk of dry mouth. It is essential to explain to this patient the necessity of remaining adherent to her medication to maintain control of her blood pressure. Since most classes of antihypertensive medication cause dry mouth, there may not be an alternate medication for this patient to try, although it can be discussed with her healthcare provider. Mrs. Simpson should take the Toprol XL one hour prior to a meal, which will help stimulate saliva production. Counsel this patient on drinking plenty of water before and after taking her medication. Toprol XL should not be crushed or cut in half. Explain to the patient that using a saliva substitute can provide relief for the dry mouth but will not cure the symptoms. Additionally she can chew gum or use lozenges to stimulate salivary flow. Basic oral hygiene practices also should be reviewed with this patient to prevent dental complications of dry mouth. This includes brushing twice daily with a fluoride-containing toothpaste, flossing daily, visiting the dentist regularly and oral self-exams. The pharmacists should encourage Mrs. Simpson to read labels carefully. Research has shown that sodium lauryl sulfate, a product found is some toothpastes, can be irritating. Also, many mouthwashes contain alcohol, another ingredient that should be avoided when dealing with dry mouth. Mrs. Simpson also may want to consider use of an oral moisturizer of saliva substitute.

TABLE 2

COMPLICATIONS

Complications of dry mouth can include nutritional, psychological and dental problems, and may affect overall health. Even when an individual is asymptomatic, dry mouth may lead to health problems ranging from minor to serious.

Lack of appropriate nutrition or decline in nutritional status due to alteration in taste is a concern in all patients, especially the elderly. Severe dry mouth can affect an individual’s quality of life due to difficulty speaking for long periods of time, chronic hoarseness, chronic sore throat and reduced oral appliance wearing time. Individuals will most often report this as a decrease in use of their dentures. According to the Oral Cancer Foundation, dry mouth is a hidden cause of gum disease and tooth loss in 3-out-of- 10 adults. ² Left untreated, dry mouth can cause increased development of dental caries, gingivitis, plaques, tooth decalcification and decay. Development of tooth decay often is further aggravated by the increased

Select medication classes associated with dry mouth

Antihypertensives (a-blockers, B-blockers, diuretics) ACE-Inhibitors (calcium channel blockers) Antidepressants (TCA, SSRI) Anxiolytics (benzodiazepines) Analgesics (opiods, NSAIDs)

TABLE 3

Dry mouth questionnaire

1. Does the amount of saliva in your mouth seem to be too little, too much or you didn’t notice?

2. Does your mouth usually feel dry?

3. Do you have difficulty swallowing?

4. Does your mouth feel dry when eating a meal?

5. Do you sip liquids to aid in swallowing dry food?

Yes to questions 1 and 2 means reduced unstimulated saliva.

Yes to questions 2, 3 and 4 means reduced stimulated saliva.

 

diabetes and dry mouth is at a much greater risk of potential dental problems if not managed properly. Although aging is not a specific risk factor for dry mouth decreased amylase and increase mucin production has been observed in the elderly. These changes cause saliva to become thicker and more viscous.

 

EVALUATION

The diagnosis of xerostomia is based on the patient’s complaints, medical history, examination of the oral cavity and other diagnostic tests.

Early detection and diagnosis of dry mouth is critical in preventing the consequences of tooth decay and other health problems. Evaluation begins with specific questions that identify patients who may be asymptomatic but still at risk of complications (Table 3). ^{4, 5} Patients seeking self-care prior to visiting their dentist or those individuals at risk of developing dry mouth also should be asked these questions by the pharmacist. The onset, frequency and severity of the dry mouth should be documented for those patients who are