Question 1: Why Is the Client Taking Medication?

The dental hygienist assesses why the client is taking medication. Generally, medications are taken for the following reasons:

To treat an acute systemic condition: Medications taken for acute conditions are generally recommended or prescribed for a defined time frame, usually of short duration, to manage the symptoms of the condition or to eliminate an infection (e.g., cough and cold preparations, antibiotics, antifungals, antidiarrheals, and pain relievers). The assumption is that when the medication is gone, so too will be the cause of the symptoms or the problem in question.

To treat a chronic systemic condition: Medications may be taken for a longer duration or for extended periods throughout the lifetime (e.g., hypoglycemics, allergy drugs, and antihypertensives).

To prevent a condition from occurring: Medications may be indicated for the prevention of a disease or condition (e.g., oral contraceptives to prevent pregnancy and daily aspirin to prevent stroke).

To prevent a recurrence of an existing condition: Medications may be used preventively to ward off the recurrence of a chronic problem (e.g., inhaled steroids for asthma and anticonvulsants to prevent seizures).

To satisfy a habit, with no clinical indication or need: Illegal street drugs have no clinical indication to justify usage. Alcohol, caffeine, and nicotine may also be included in this category. Other drugs, such as daily aspirin and vitamin supplements, may be taken habitually without any documented clinical need or because of a perceived health benefit that may or may not exist. Box 12-2 lists common drug classes with indications for their use.

Question 2: Are Symptoms Reported during the Client’s Health History Interview Caused by a Medical Condition, or Are They Drug Side Effects?

Answering this question is a difficult challenge; therefore attention must be paid to findings from the health history interview. The dental hygienist attempts to match the physical findings or symptoms reported by the client with existing medical or dental conditions. Drugs from the medication list should be suitable for the medical and dental conditions for which the client is being treated. Consider that a doctor may prescribe a medication for an off-label use. When symptoms do not correlate with known conditions, the dental hygienist must then discern whether the client’s medications may be contributing to the problem or whether there may be an undiagnosed condition, either of which could explain the client’s symptoms.

The following questions facilitate problem solving:

Does the client have a known systemic condition?

What are the symptoms reported by the client?

Do these symptoms correlate with the client’s known systemic condition?

Do the symptoms reported indicate the presence of an undiagnosed condition?

What are the indications for the drugs being taken?

Could the drug(s) be causing or contributing to the symptoms in question?

Question 3: What Are the Adverse Effects of This Drug?

All drugs have the potential to cause harm. When a drug is selected for use, the potential harm must be carefully weighed against its benefits. Drugs are extensively tested and regulated by the U.S. Food and Drug Administration (FDA) to ensure safety and efficacy. The FDA requires the reporting of all known adverse drug effects, which can be found in drug reference guides and accessed from the FDA website (see Box 12-1, Chairside Drug References, and information and resources at the Evolve website).

Drugs interact with target tissues to produce a desired effect, also known as the therapeutic effect. In addition, drug may also interact with nontarget tissues, resulting in effects that differ from the therapeutic effects. These undesirable effects are also known as drug side effects, the severity of which is dose-related. For example, a client takes an angiotensin-converting enzyme (ACE) inhibitor to treat her hypertension, and although it lowers her blood pressure, she experiences a persistent dry cough. All drugs produce side effects, but most are tolerable and disappear when the drug is discontinued (Box 12-3). The FDA requires the reporting of all known side effects, which are organized by body system and the percentage of population affected.

Drug toxicity refers to toxin-induced cell damage and cell death from a medication. Usually a drug does not produce damage directly to the cell itself. Rather, the damage is caused by an active metabolite formed during metabolic breakdown by the liver or kidneys. Metabolites cause biochemical damage to cellular components, resulting in altered metabolism of the affected cell, cell mutation, or cell death. Unlike side effects, toxicity reactions cannot be tolerated and cause permanent tissue damage on either the microscopic or macroscopic level. These are especially dangerous if major organ systems are involved. Drugs that produce these types of reactions may be labeled as hepatotoxic (causing liver damage), nephrotoxic (causing kidney damage), neurotoxic (causing nerve damage), or cardiotoxic (causing heart damage). Drug toxicity frequently occurs when the drug dosage exceeds the therapeutic level (drug overdose).

Drug hypersensitivity occurs when either the drug or its metabolites act as immunogens, triggering the immune response. Repeated exposure to the same drug produces this allergic response. Signs of a true allergic reaction include skin rash, itching, hives, bronchospasm, and rhinitis. Life-threatening allergic reactions include anaphylaxis, hemolysis, and bone marrow suppression. Allergic reactions are managed with epinephrine, corticosteroids, antihistamines, and assistance from emergency support personnel. Allergic reactions are dangerous because they are not predictable and are not dose related. Clients with a history of allergy to a drug in any given class will be allergic to all of the drugs in the same class. In addition, some drugs, such as the penicillins and the cephalosporins, show cross-sensitivity to other drug groups with similar chemical structures. The dental hygienist must recognize the warning signs of an allergic reaction so that appropriate treatment interventions can be administered promptly (see Chapter 8).

Other adverse drug effects include negative effects on fetal development, or teratogenicity. Many drugs cross the placenta and are secreted in breast milk; therefore drugs are not tested in pregnant and lactating women. The FDA labels each drug with a pregnancy risk factor (A, B, C, D, X) that corresponds to one of five categories indicating the potential of a systemically absorbed drug to cause birth defects (see Chapter 53, Table 53-3). FDA pregnancy categories are published in all major drug reference texts.

Occasionally a client experiences a side effect that is completely unexpected or qualitatively different from any known published side effects. This unique response to a drug is called a drug idiosyncrasy. Clients may also report drug tolerance, which manifests as the need to take larger doses of the drug to produce the same response. This is one mechanism that can lead to drug addiction.

To answer Question 3, the dental hygienist assesses the following:

What are the known published side effects of the drug(s)?

Could the symptoms reported by the client be side effects of the drug(s)?

Are reported symptoms indicative of a drug allergy?

Question 4: Are There Potential Drug Interactions?

Adverse drug effects can also be caused by drug interactions, the negative effects that can occur when two or more drugs are taken simultaneously. Drug interactions range in severity from mild alterations in drug action to life-threatening conditions in the client (e.g., alterations in drug efficacy, toxicity reactions, or other dangerous reactions such as hypertensive crisis, extended bleeding time, or respiratory depression).

Adverse drug interactions are prevented by knowing drug relationships. Dental professionals keep apprised of drug interactions by routinely reviewing lists of known interactions in standard drug reference texts and scientific publications. Drug interactions arise from a variety of mechanisms, and result in either a decreased or an increased effect of one or more drugs. The greater the number of medications taken, the greater the likelihood of experiencing an interaction (Table 12-1). To assess whether the client is experiencing a drug interaction, the dental hygienist consults a drug reference text and assesses the following:

Are there any known drug interactions for this medication?

Could the client’s symptoms be indicative of a drug interaction?

TABLE 12-1 Common Drug Interactions Significant in Oral Care

From Wynn RLL, Meiller TF, Crossley HLT: Drug information handbook for dentistry, ed 12, Hudson, Ohio, 2006, Lexi-Comp.

Question 5: Do These Findings Suggest a Problem with Drug Dosage?

Standard drug dosage schedules may be too strong for children and elderly clients and may need to be altered to prevent adverse drug effects. The need to reduce drug dosages in these populations is directly related to drug pharmacokinetics, which refers to how the drug is absorbed, distributed, metabolized, and excreted from the body. Children demonstrate an increased skin and mucous membrane permeability; therefore they absorb medications much more readily and more quickly than their adult counterparts. Pediatric dosage is based on the weight of the child. In general, dosages for children are half of the standard adult dose.

In the elderly, normal physiologic changes of aging dictate the need for a reduction in dosage. Increased stomach acidity alters drug absorption into circulation. Normally the liver converts lipid-soluble drugs to water-soluble metabolites, thus inactivating the drug and allowing for filtration and elimination by the kidney. Both liver and kidney function decline with age; therefore more drug stays active after passing through the liver, and the portion of the drug that remains lipid soluble is scavenged by the kidneys and either put back in circulation or stored in body fat. Production of plasma proteins, the binding sites for drugs in circulation, also declines with age. The portion of the drug that is unbound in the circulation is the active drug. The amount of active drug in circulation increases when the client takes multiple medications, all of which are competing for fewer binding sites. These physiologic changes manifest as an increased drug effect in the client and contribute to unwanted adverse drug effects such as sedation, confusion, and extensions of desired therapeutic effects. As with children, doses for the elderly may need to be reduced to half of the standard adult dosage. To assess the potential for complications caused by drug dosage, the dental hygienist considers the following:

Have the client’s age and weight been taken into account when determining drug dosage?

Could the symptoms be attributed to altered drug pharmacokinetics caused by normal physiologic changes of aging?

Question 6: How Is This Client Managing Medications?

Most clients take multiple medications and are treated by many different healthcare providers. The lack of communication among these providers, all of whom may be prescribing medications, results in an increased risk for adverse drug reactions. The dental hygienist, as client advocate, encourages client compliance and assesses risks associated with medication use.

The client’s ability to manage medications is confounded by a number of variables. First, the client may be self-medicating with either OTC or prescription medications or both. Clients are usually unaware of potential adverse drug effects that can occur as a result of mixing medications, altering recommended dosage schedules, or mixing medications with supplements, alcohol, or certain foods. Second, clients may not read the warning labels on the medication packaging or may not understand what they are reading. This is especially true when labels warn against using certain classes of drugs or warn against using the medication because of a preexisting condition. The client may not be aware that he or she has a preexisting condition, such as enlarged prostate, hypertension, or thyroid disease. Other clients simply choose to ignore the warnings and take the medication anyway. The small typeface on many labels poses yet another challenge for the elderly and the visually impaired.

Failure to comply with medication use, intentional or unintentional, must be discerned by the dental hygienist. The dental hygienist never assumes that the client intuitively understands the prescribed regimen or reads the instructions from the pharmacy. Whenever a drug is dispensed or prescribed from the dental office, the dental hygienist provides detailed instructions. Even clients who are normally compliant are given instructions and an opportunity to ask questions to reinforce adherence to the prescribed regimen.

Familiarity with a routine can breed laziness in compliance. Just as clients learn proper dosage schedules, they can also learn to give the “right answer” to inquiries about taking their medications. In these instances the dental hygienist must rely on the client’s physical presentation as well as personal intuition to discern whether the client is truly following instructions. How well a client complies with medication use can reflect the client’s willingness to comply with other professional recommendations, including self-care instructions and referrals.

Dental hygienists also facilitate information transfer between the client and other healthcare professionals. A call to the client’s physician can clarify discrepancies in the client’s understanding of her medications and can confirm that it is safe to provide treatment. Conversations between the dental hygienist and other practitioners should be documented in the services rendered portion of the client record. When assessing client compliance with medications, the dental hygienist focuses on:

How many medications is the client taking?

When was the client last seen by a physician? By the physician who prescribed the medication?

What is the prescribed regimen for the medications?

How many providers are prescribing medications for the client?

How long is the client to remain on this medication?

Does the client understand why the medication was prescribed?

Have client instructions been provided for taking the medications? If so, by whom?

Does the client understand the instructions for using the medications?

Is the client self-medicating? Undermedicating or overmedicating?

How many refills are there for the medication?

Has the medication expired?

Question 7: Will Any Oral Side Effects of This Medication Require Intervention?

Management of oral side effects is an ongoing challenge (Box 12-4). Oral side effects cause client discomfort and interfere with the ability to chew, swallow, and digest food. Some oral side effects place the client at risk for oral trauma, and others lead to infection, pain, and possible tooth loss.⁴ Dental hygienists need to recognize these oral conditions in a timely manner and recommend appropriate treatment interventions. Professional intervention is often necessary to improve client comfort and function.⁵

Over 500 medications cause xerostomia, making it the most commonly reported oral side effect, especially among elderly clients (Box 12-5).^6-8

Drug-induced xerostomia is a combination of reduced salivary flow rate and a change in both the nature and quality of the residual saliva.⁹ Residual saliva is more mucinous and viscous, facilitating food and oral biofilm adherence to tooth surfaces, appliances, dentures, and oral tissues. The client will retain more food in the buccal vestibule after eating owing to the loss of natural salivary cleansing. The pH of the mouth becomes more acidic because of the reduction of natural physiologic buffers, which, combined with oral biofilm and food accumulation, places the client at increased risk for dental caries. Xerostomia-induced dental caries are evident along the gingival margin on exposed buccal and lingual root surfaces, at and underneath crown margins, and in root furcations. Caries can lead to extensive tooth destruction and tooth loss, which is particularly significant for teeth that serve as anchors for dental prostheses. Increased biofilm acidity also contributes to dentinal hypersensitivity. Clients with xerostomia should be placed on supplemental daily fluoride and amorphous calcium phosphate therapy to reduce caries and dentinal hypersensitivity risks (see Chapters 31 and 38). Incorporating daily therapeutic doses of xylitol-containing mints and gums may also be recommended to reduce Streptococcus mutans and stimulate saliva production. Symptomatic relief of dry mouth and dry throat may be obtained through the use of artificial salivary substitutes or by taking pilocarpine (Salagen) or cevimeline (Evoxac), cholinergic drugs that stimulate serous salivary flow (see Chapter 44Table 44-2Box 44-9).¹⁰

Under normal conditions, saliva maintains the balance of the oral ecosystem with immunologic and antibacterial processes that regulate the population of oral flora. When the ecosystem becomes unbalanced, the proportions of pathogenic and opportunistic organisms increase. Therefore the person is at greater risk for oral infections, including gingivitis, periodontitis, and both viral and fungal infections. People with xerostomia greatly benefit from the use of daily antimicrobial therapy at home. Chlorhexidine and essential oil mouth rinses have demonstrated efficacy against periodontal pathogens and fungal organisms (see Chapter 29).¹¹ Fungal infections are associated with use of antibiotics, immunosuppression, and underlying systemic diseases such as diabetes mellitus. Prescription antifungal therapy (e.g., nystatin) is indicated, and often repeated, in xerostomic clients with recurrent fungal infections. Fungal infections may manifest as white plaques overlying red oral mucosa, burning mouth syndrome, symptomatic geographic tongue, and angular cheilitis (see Chapters 53, 54, and 55).

Salivary mucins lubricate the oral mucous membranes, protect against ulceration and penetration of toxins, and assist with wound healing and repair. Xerostomic clients have friable mucous membranes, which are highly susceptible to trauma from toothbrushing, mastication, and rubbing against appliances and dentures. Chlorhexidine and essential oil mouth rinse have been shown to reduce the incidence and severity of aphthous ulcerations when used preventively on a daily basis. There are numerous OTC products available for topical pain control associated with aphthous ulcerations and oral mucositis; most contain benzocaine to improve comfort. Prescription lidocaine in the form of a rinse may also be used for pain relief (see Chapter 44Table 44-1Box 44-7Figure 44-2 for the treatment of oral mucositis).

Salivary mucins also play a role in initiating the breakdown of food in preparation for swallowing and digestion. Often, xerostomic clients will experience gastrointestinal disorders related to their inability to adequately digest food. These problems are further compounded in clients taking medications that cause taste alteration as a side effect. These adverse effects may lead clients to make poor food choices or stop eating because of discomfort, disinterest, or chewing difficulties. Clients may experience weight loss, which alters the fit and comfort of dentures and appliances, leading to a cycle that requires intervention. Weight loss and poor nutritional status are of great concern in those with serious medical conditions or those undergoing cancer therapy (see Chapter 44).

Phenytoin (Dilantin) (seizure medication), cyclosporine (Sandimmune) (organ transplant antirejection drug), and some calcium channel blockers (antihypertensives) all cause drug-influenced gingival enlargement as a side effect.¹² Black, hairy tongue is typically associated with antibiotics. Other medication-induced oral side effects include glossitis, erythema multiforme, lichen planus, and taste alteration.⁴ The dental hygienist should consult a drug reference guide to verify the potential for a drug to produce these adverse effects. For a list of strategies to manage oral side effects associated with medication use, see Box 12-6. To determine the need for intervention, the dental hygienist considers the following:

Is the client having difficulty speaking, chewing, swallowing, wearing dental appliances?

Is the client taking medications that could be contributing to these problems?

Has the client reported changes in weight that could be attributed to a change in nutritional status?

Are oral assessment findings consistent with known side effects of the drugs that the client is taking?

Question 8: Given the Pharmacologic History and Other Assessment Data, What Are the Risks of Treating This Client?

Assessing the risk of proceeding with treatment is the final and most important determination made. Treatment risks associated with medication use vary in nature and severity and are not always obvious. To assess risk, the following questions must be considered:

If treatment is initiated, will the client be placed in a situation that is potentially dangerous or life-threatening?

Will the planned treatment temporarily or permanently compromise the client’s health or ability to function?

Will the treatment compromise the client’s safety or comfort?

Will the treatment compromise the provider’s safety or comfort?

Life-threatening risks are associated with conditions for which the client is taking medication or with side effects. Clients who are immunocompromised from cancer chemotherapy, organ transplant antirejection therapy, or acquired immunodeficiency syndrome (AIDS) are at greater risk for developing infections from poor oral hygiene or invasive dental hygiene procedures (see Chapters 44, 45, and 48). Good oral self-care practices, preprocedural antimicrobial rinsing, and prophylactic antibiotic premedication are strategies to minimize the risk for infection. Antibiotic therapy associated with professional care is determined in consultation with the dentist or physician on a case-by-case basis (see Chapter 10).

Risk for hypertensive crisis and stroke is associated with the use of vasoconstrictors, and the dental hygienist must verify the compatibility of administering epinephrine with all medications taken by the client before giving an injection (see Chapter 39). Use of cocaine sensitizes clients to norepinephrine, posing an even greater risk for hypertensive crisis, heart attack, and stroke in the oral care environment. Myocardial infarction, stroke, and anaphylaxis from an unexpected allergic reaction are perhaps the most dangerous risks. Insulin shock, aspiration, and seizures are mostly preventable with proper client assessment and use of safety precautions.

The dental hygienist is exposed to personal health risks when treating clients with medications. Inhalation risks are associated with general anesthetics and nitrous-oxide and oxygen systems with inadequate scavenging systems (see Chapter 40). For example, pregnant practitioners should exercise caution when in the presence of nitrous oxide, a drug that causes spontaneous abortion as a teratogenic effect (capable of producing genetic mutations). However, use of a proper scavenging system significantly minimizes this inhalation risk. Topically applied agents have the potential to come in contact with the skin, mucous membranes, and eyes, requiring the use of personal protective equipment (see Chapter 7). The hygienist must also assess the treatment environment for potential hazards to protect both hygienist and client in case a client falls or has a seizure.

All dental hygienists must be currently certified in cardiopulmonary resuscitation (CPR) and managing medical emergencies in the dental office. The dental hygienist can be especially helpful in establishing a safety plan that includes monitoring oxygen tanks to ensure that adequate levels are always available, the expiration dates on emergency medications, and the use of medications dispensed from the office (see Chapter 8).

Dental hygienists should use laboratory test results, medical records, and information obtained from the dentist, physician, and pharmacist to assist with clinical decision making. Maintaining a client’s systemic health always takes priority over dental hygiene care needs, and treatment should never be initiated when there is concern about the client’s safety (see Chapter 10). Both the client and the dental hygienist must know about any medication risks associated with treatment, and they should be thoroughly explained and documented in the treatment record.

CLIENT EDUCATION TIPS

Inform clients about why medications are being prescribed.

Describe what the client should expect while taking the medications.

Explain in simple terms what the medication will do, its potential side effects, and proper dosage schedule.

Explain the difference between side effects and drug allergies.

Describe the signs of an allergic reaction (itching, hives, shortness of breath, or respiratory distress).

Explain what to do in case of an allergic reaction.

Identify known drug interactions (“Do not take drug X when taking drug Y”).

Give any special instructions relevant to the medication (e.g., avoid sun exposure, take the medication until it is gone).

Suggest ways to minimize side effects (e.g., drink a full glass of water, eat before taking the medication).

Emphasize that no herbal medication should be taken without a physician’s approval.

LEGAL, ETHICAL, AND SAFETY ISSUES

Ensure that all instructions and answers to client questions are accurate and complete. Ask for assistance if it is necessary to answer questions completely.

Check each client’s health history for known allergies or previous reactions to ensure compatibility.

Give written instructions to which the client can refer at home.

Document in the treatment record what the client was told.

Caution clients about the dangers of drug interactions and overmedication possible with over-the-counter and herbal medications.

KEY CONCEPTS

The pharmacologic history provides clues regarding a client’s general health status and health behaviors and protects the client’s health and safety.

Using a logical, systematic approach to history taking helps the dental hygienist formulate questions and evaluate client responses to safely provide care.

Interpreting data obtained from the eight fundamental questions of the pharmacologic history enables the dental hygienist to assess the risks of treating clients taking medications.

All drugs have the potential to cause adverse effects.

Drug interactions range in severity from mild alterations in drug action to life-threatening conditions in the client.

Standard drug doses are too strong for children and the elderly and need to be altered to prevent adverse effects.

The dental hygienist is a client advocate who facilitates client compliance and education on medication use.

Clients may fail to comply with medication use for several reasons including multiple providers prescribing multiple medications, self-medication, cost, and failure to comply accurately with the prescribed dosage regimens.

Oral side effects of medications cause client discomfort; interfere with the ability to chew, swallow, and digest food; and increase risk for infection and tooth loss.