One of my favorite patients in residency was a lady in her seventies who had longstanding high blood pressure, high cholesterol, and diabetes.

Each time she visited the office, I would recommend that we start multiple medications to control these conditions, and every time she would politely decline. Her previous physicians had left frustrated notes in her chart littered with terms such as “non-compliant,” “against medical advice” and expressing wonderment why she even bothered to show up.

I wondered, too — for show up she did, never missing an appointment but always turning down every drug we offered.

This type of patient drives most doctors nuts. I took a more philosophical approach: at least I knew exactly where she stood. Other patients, I suspected, simply accepted proffered prescriptions without protest and then never went to a pharmacy to fill them. Later, as an attending physician, the first thing I’d tell students who wanted to reflexively increase the dose of an apparently ineffective drug was, “make sure that they’re actually taking the meds.”

The extent of the problem of “primary medication non-adherence” (not filling the initial prescription for a new drug) became much clearer with the publication of a study in the April 2010 issue of the Journal of General Internal Medicine that found that a whopping 28% of new prescriptions were never filled.

What were the most common types of drugs that patients never picked up? Those for high blood pressure, high cholesterol, and diabetes.

There are many potential explanations for why patients don’t take prescribed drugs, ranging from cost to convenience to the patient’s not being totally convinced that the drug is necessary to treat an asymptomatic condition. But many doctors aren’t really interested in talking to patients about it, asserted surgeon Pauline Chen in a recent New York Times column:

While anyone who has ever tried to complete a full course of antibiotics can understand how easy it is to skip, cut down or forget one’s medications altogether, bringing the topic up in the exam room feels more like a confession or inquisition than a rational discussion. Few of us want to talk about medication non-adherence, much less admit to it.

Fair enough. But there are plenty of good reasons to change this mindset. Prescriptions that aren’t filled can’t do any good, but they can easily do harm: for example, in the diabetic patient who is hospitalized for an infection and given his “regular” insulin dose, only to become comatose from low blood sugar because he never actually took that dose (which his puzzled physician kept increasing) in real life.

The patient I mentioned earlier eventually suffered a stroke, the unfortunate consequence of not taking medications for her conditions. Had I assumed that she had been taking her medications, however, my colleagues might have pursued a more aggressive — and totally unnecessary — workup to explain the cause of the stroke.

Instead, she returned to my care a changed woman, resolved to take the drugs that she’d previously avoided, and her blood pressure, cholesterol, and blood sugar rapidly returned to normal. An interesting finding in the non-adherence study was that patients were less likely to fill prescriptions of specialists than those of primary care physicians. It goes to show that a family doctors know that their job isn’t done once the prescription is written. If that’s all it took, we — and the specialists who often have more tenuous relationships with patients — might as well be pharmacists.

Kenneth Lin is a family physician who blogs at Common Sense Family Doctor.

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