Dry Mouth

Dry mouth, also known as xerostomia, refers to a patient’s report of mouth dryness, usually occurring when salivary secretion is half of the individual normal rate, though dry mouth may also occur with normal secretion.¹Dry mouth can lead to difficulties in chewing, speaking, swallowing, and tasting, and increase the chance of developing dental caries, and infections.²Dry mouth can result from autoimmune diseases,¹chronic medical conditions, increased levels of stress,²medications, methamphetamine abuse, nervousness,²radiation treatment, and smoking.

The aging process has been associated with changes in saliva. However, dry mouth is more common secondary to medication use.¹An extensive list of medications that can cause it include amiloride, amitriptyline, amoxapine, amphetamines, benztropine, bupropion, cetirizine, chlorpromazine, clemastine, clomipramine, clonidine, clozapine, cyclizine, cyclobenzaprine, cyproheptadine, desipramine, diazepam, dicyclomine, didanosine, doxazosin, doxepin, duloxetine, ephedrine, fluoxetine, fluvoxamine, granisetron, guanfacine, hyoscyamine, ibuprofen, interferon alpha, ipratropium bromide, isotretinoin, ketoprofen, ketorolac, levodopa, lithium, loratadine, maprotiline, methyldopa, mirtazapine, morphine, nortriptyline, olanzapine, omeprazole, ondansetron, oxybutynin, pentoxifylline, phenelzine, promethazine, propafenone, propantheline bromide, quetiapine, risperidone, rizatriptan, selegiline, sertraline, sucralfate, terazosin, tolterodine, topiramate, tranylcypromine, trazodone, triazolam, trihexyphenidyl, trimipramine, venlafaxine, and zopiclone.³The medical causes of dry mouth include autoimmune disorders; dehydration; endocrine disorders, such as diabetes mellitus, and hypothyroidism; genetic diseases, such as celiac disease, and cystic fibrosis; Down syndrome; infections, such as hepatitis C, and HIV; neurological disorders, such as Bell palsy, and Parkinson disease; psychological conditions; and viral infections. A patient’s report of dry mouth is subjective, and can be challenging to manage, given that the degree of oral dryness varies from patient to patient.¹It is imperative for the provider to address this, given that saliva has antimicrobial properties, including immunoglobulin E antibodies and lactoperoxidase, thus helping oral health.⁴

CASE STUDY

Jane is a 50-year-old female who presents to the clinic with complaints of “cotton mouth.” She recently moved from Colorado to Ohio, and has noticed that her allergies have been “acting up,” and reports nasal congestion and sneezing. Jane says she is taking Benadryl 25 mg every night at bedtime, and Claritin 10 mg daily. Because she can no longer tolerate her dry mouth and drinking water has provided no relief, she has made an appointment with her primary care provider. Jane denies chills, fever, rash, recent illness, and weight changes. She reports smoking socially on occasion and does not drink alcohol. Jane denies any history of using recreational drugs.

Discussion Question:What additional information would you want to know about Jane’s history and presentation?

Answer:Getting her comprehensive medical history—including autoimmune diseases, chronic conditions or illnesses, drugs used, nutrition, and a past history of radiation—is essential.¹

The provider should ask Jane whether she has any ocular symptoms, such as a burning, gritty feeling in the eye, itching, and ropy secretions, which would suggest Sjögren syndrome.⁵The provider should also ask whether there are any symptoms of thyroid dysfunction, including bowel pattern changes, depression, dry skin, fatigue, headaches, intolerance to cold, lethargy, menorrhagia, muscle cramps, and weight changes.⁵Also ask Jane about her symptoms, including her ability to swallow dry foods, dryness in relation to eating, whether the symptoms occur constantly or only at night, her perception of the amount of saliva she has, and her use of fluids to aid in swallowing.¹

Discussion Question:What findings during the physical exam would warrant further investigation?

Answer:These would warrant further investigation: acanthosis nigricans, bradykinesia, delayed deep tendon reflexes, diastolic hypertension, dry eyes, an enlarged thyroid, eruptive xanthomas, a high waist circumference, jaundice, parotid gland enlargement, photophobia, postural instability, pruritus, a puffy face and eyelids, rigidity, skin color changes including pallor and yellowing, skin infections, thin nails or hair, peripheral edema, tremors, and vaginitis.^5-9

Discussion Question:What tests can aid in assessing an underlying condition?

Answer:Jane is taking medication that causes dry mouth as an adverse effect. If she has had other associated signs and symptoms, testing could include a complete blood count, enzyme-linked immunosorbent assay testing, hepatitis C virus antibody testing, glycated hemoglobin or glucose testing, a thyroid panel, and Western blot analysis. American-European Consensus Group classification and American College of Rheumatology classification criteria can be used when diagnosing Sjögren syndrome.¹⁰

Discussion Question:What treatment options are available if removing the offending agents does not resolve Jane’s complaint of dry mouth?

Answer:Removing the offending agents, including Benadryl and Claritin, is an option. A trial of Flonase¹¹and removing Benadryl first followed by Claritin can be initiated to see whether Jane reports adequate management of her allergies without the adverse effects of dry mouth. If removing the offending agents does not alleviate her dry mouth and no underlying condition can explain her subjective report, a cholinergic agonist, such as bethanechol or pilocarpine, can be prescribed.³Pilocarpine is contraindicated in patients with acute iritis, liver impairment, or uncontrolled asthma.¹

Discussion Question:What are the follow-up recommendations?

Answer:Advise Jane to follow up with her dentist or dental hygienist often, perform oral hygiene, and monitor for complications such as oral candidiasis.¹

References

1. Glare R, Spiteri-Stains K, Paler V. A patient with dry mouth.Clin Otolaryngol. 2009;34(4):358-63. doi: 10.1111/j.1749-4486.2009.01930.x.
2. Dry mouth. National Institute of Dental and Craniofacial Research website. nidcr.nih. gov/OralHealth/Topics/DryMouth/DryMouth.htm. Accessed February 4, 2018.
3. Drug-induced taste disturbances. Pharmacist’s Letter website. pharmacistsletter.thera- peuticresearch.com/pl/Browse.aspx?cs=&s=PL&pt=6&fpt=31&dd=330219&pb=PL&- cat=3742. Published February 2017. Accessed March 6, 2018.
4. Hupp WS. Management of dry mouth. In: Bope ET, Kellerman RD, eds.Conn’s Current Therapy.1st ed. Philadelphia, PA: Elsevier; 2017:949-954.
5. Hellman DB, Imboden JB Jr. Rheumatologic & immunologic disorders. In: Papadakis MA, McPhee SJ, eds.Current Medical Diagnosis & Treatment. 57th ed. New York, NY: McGraw Hill Education; 2018:834-892.
6. Fitzgerald PA. Endocrine disorders. In: Papadakis MA, McPhee SJ, eds.Current Medical Diagnosis & Treatment. 57th ed. New York, NY: McGraw Hill Education; 2018:1117-1221.
7. Masharani U. Diabetes mellitus & hypoglycemia. In: Papadakis MA, McPhee SJ, eds.Current Medical Diagnosis & Treatment. 57th ed. New York, NY: McGraw Hill Education; 2018:1222-1268.
8. Friedman L. Liver, biliary tract & pancreas disorders. In: Papadakis MA, McPhee SJ, eds.Current Medical Diagnosis & Treatment. 57th ed. New York, NY: McGraw Hill Education; 2018:685-745.
9. Aminoff MJ, Douglas VC. Nervous system disorders. In: Papadakis MA, McPhee SJ, eds.Current Medical Diagnosis & Treatment. 57th ed. New York, NY: McGraw Hill Education; 2018:986-1058.
10. Ranatunga SK. Sjogren syndrome. Medscape website. emedicine.medscape.com/article/332125-overview. Updated February 12, 2018. Accessed February 28, 2018.
11. Sheikh J. Allergic rhinitis medication. Medscape website. emedicine.medscape.com/article/134825-medication. Published November 15, 2017. Accessed February 4, 2018.