It has been estimated that half of all Americans older than 18 years take at least one prescription medication, while 7 percent take five or more prescription drugs.¹ The highest user rate of prescription drugs was found among people older than 65 years, and among this group, 23 percent of women took at least five different medications.

Polypharmacopeia among our patients has become the norm rather than the exception. This trend poses several challenges for oral health care professionals, the most obvious being drug interactions between patients’ medications and the pharmacological agents used in dentistry. In addition, side effects having oral manifestations may become more common, and certain systemic effects may require modification of otherwise routine dental procedures.

One often-neglected but important aspect of medical care, one in which oral health care professionals may have a great impact, is patient adherence to medication regimens.² Beyond providing safe and appropriate dental care, oral health care professionals are recognized as part of the overall health care team for patients with medical problems. Different medical groups are promoting the role of dentists in the screening and monitoring of patients. For example, in the latest hypertension guidelines from the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, dentists are mentioned as health care professionals who should work together with physicians to assist patients with achieving good blood pressure control.³

About 25 percent of patients taking medications do not adhere to drug regimens given to them by their physicians. The adherence rate for treatment of chronic conditions usually is lower than the adherence rate for acute illnesses. A dramatic drop-off is noticed at about six months after the initiation of therapy. Even the use of life-saving medications, such as cholesterol-lowering drugs, may be discontinued by 50 percent of patients within six months.⁴

There are several problems associated with nonadherence to medication therapy: deterioration of the underlying condition, development or progression of comorbidities, increased contagion, increased mortality and increased health care costs. A recent study found, not surprisingly, that proper adherence to medication regimens was associated with a positive health outcome, while non-adherence created a risk of increased morbidity and mortality.⁵

Interestingly, the same result also was found for adherence to placebo therapies in different research studies. It is not clear why a placebo medication should have a positive effect on health outcomes, but it has been speculated that adherence to a medication regimen in itself may be a marker of generally healthy behavior.⁵

A phenomenon known as "white-coat adherence" has been described, in which patients improve their adherence to medication therapy within five days before and after seeing their physicians, as compared with 30 days after a medical visit.^6,7 This is a concern for oral health care providers, as it may not be clear if the medication the patient reports to have been prescribed actually has been used in a proper manner.

Adherence to medication regimens is particularly challenging for patients being treated for chronic diseases and conditions with few immediate symptoms, such as hypertension, hypercholesterolemia and type 2 diabetes mellitus, as well as for prevention and treatment of tuberculosis. In these cases, the patient may not actually see or feel the benefit of the therapy and therefore may be comparatively careless about adherence.

Other barriers to adherence have been identified, among them forgetfulness, differing priorities, intentional decisions to omit a dose or doses of the medication, emotional factors, complex drug regimens, drug regimens that do not suit patients’ lifestyles, high cost of medication and a failure of the prescribing health care professional to explain the benefits of taking the medication.⁸ Conversely, patients show more motivation to adhere if they understand the illness and treatment, the benefit of the treatment and the possible adverse effects of nonadherence.

Most health history forms used in dentistry have at least one question about the patient’s medications. Usually, however, the questions address only specific drug allergies or whether the patient is taking certain medications. We need to add a query about adherence. As former Surgeon General C. Everett Koop once observed, "Drugs don’t work in patients who don’t take them."

The involvement of oral health care professionals in monitoring adherence to drug regimens may achieve important goals: better control of the progression of the underlying illness and promotion of a healthy behavior that may, in turn, cross over into other areas associated with a healthier lifestyle.