In order for medication to work, getting a prescription filled isn’t enough. You have to actually take the medication. And that’s where you (the patient) come in. Estimates vary based on the population and the medication, but a reasonable assumption is that 50% of people given a prescription don’t take their medication as prescribed. In pharmacy terminology we usually call this medication compliance, but because that sounds a bit paternalistic, the term medication adherence is also used. People forget doses, deliberately skip doses, and sometimes even take more than directed. Often, the prescription isn’t finished completely. Perhaps not surprisingly, people are less likely to adhere to their prescribed medication schedule when the condition they are treating has no symptoms. All things being equal, you’re more likely to take your pain control medicine than your hypertensive medications: Pain medications have side effects, but should help you feel better right now. Hypertension medications can only make you feel worse. Statins (as a group of medications) are another good example. We treat high cholesterol to lower the risk of heart disease: heart attacks, strokes, and death. It has no obvious benefit now, nor will we ever be able to point to the benefit we received. We’re taking the medication to reduce the risk of something happening in the future. If the drug isn’t taken regularly (or at all) then you’re not going to get the expected benefits of statin therapy. The “value” that treatment delivers is reduced (or eliminated). And if you stop a medication periodically, then restart it, you might get more side effects than you would have if you just took it regularly. (more…)
Posts Tagged adverse events
If there’s one thing I’ve been consistent about, it’s that, however ridiculous all the other woo I routinely discuss here is—homeopathy, reiki, reflexology, I’m talking to you and your friends—herbal medicine and supplements might have value because they might have a physiological effect that is beneficial in treating or preventing disease. Of course, if that’s the case, it’s because the herb or supplement contains chemicals that act as drugs. They’re “dirty” drugs in that they are mixed with all sorts of other substances in the herb or supplement that might or might not have effects, which means that different lots of the herbs or supplements often have different activity, but they are drugs nonetheless. That’s why, for instance, doctors don’t tell patients to chew on foxglove leaves when they want a patient to get digoxin. Digoxin is a powerful drug with a relatively narrow “therapeutic window,” meaning that the difference between the levels of the drug in the blood needed for therapeutic effect are not very far from toxic levels; so predictable, reliable drug content is essential. I just learned a while ago that within the living memory of some older physicians digoxin actually was prescribed as crude extracts, which was very difficult and dangerous, hence the necessity of purification. In other cases, (such as Artemisinin, for which Youyou Tu was recently awarded the Nobel Prize in Physiology or Medicine), crude plant extracts do not contain sufficient quantities of the active component, necessitating its isolation, purification, and, in some cases, chemical modification to increase its absorption, stability, or activity.
One thing that proponents of herbal medicine and supplements often forget, though, is that if herbs or supplements can have potentially beneficial effects (albeit difficult to regulate effects due to the crude, impure nature of the extracts often used) because they contain drugs, then herbs and supplements can also produce adverse events, again, because they contain drugs. You can overdose on herbs and supplements. This point was recently reinforced by a new study by Geller et al. published last week in the New England Journal of Medicine (NEJM), entitled “Emergency Department Visits for Adverse Events Related to Dietary Supplements.” It was carried out by investigators from the Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, and Chenega Government Consulting; and the Center for Food Safety and Applied Nutrition and the Division of Public Health Informatics and Analytics and the Division of Dietary Supplement Programs, Food and Drug Administration. The title pretty much tells you what the study is about, and what the study is about is that dietary supplements cause a lot of visits to the emergency room every year; 23,005 (95% confidence interval [CI], 18,611 to 27,398) emergency department visits per year can be attributed to adverse events related to dietary supplements.
Is the best medicine no medicine at all? Sometimes. My past posts have emphasized that the appropriateness of any drug depends on an evaluation of benefits and risks. There are no completely safe interventions, and no drug is free of any side effects. Our choice is ideally informed by high-quality data like randomized controlled trials, with lots of real-world experience so we understand a drug’s true toxicity. But when it comes down to a single patient, treatment decisions are personalized: we must consider individual patient characteristics to understand the expected benefits and potential harms. And in a world with perfect prescribing and drug use, harms wouldn’t be eliminated, but they would be minimized. Unfortunately, we’re not there yet. There is ample evidence to show that the way in which prescription drugs are currently used causes avoidable harms to patients.
The art and science of medicine is a series of interventions to improve health. In making these treatment decisions, we strive to minimize iatrogenic harm — that is, harms caused by the intervention itself. High up on the list of of avoidable harms are adverse events related to drug treatments. Audits of adverse events are astonishing and shameful. Studies suggest 28% of events are avoidable in the community setting, and 42% are avoidable in long-term care settings. That’s a tremendous amount of possible harm resulting from treatments that were prescribed to help. And the group that is harmed the most? The elderly. (more…)
All informed health decisions are based on an evaluation of expected risks and known benefits. Nothing is without risk. Drugs can provide an enormous benefit, but they all have the potential to harm. Whether it’s to guide therapy choices or to ensure patients are aware of the risks of their prescription drugs, I spend a lot of time discussing the potential negative consequences of treatments. It’s part of my dialogue with consumers: You cannot have an effect without the possibility of an adverse effect. And even when used in a science-based way, there is always the possibility of a drug causing either predictable or idiosyncratic harm.
An “adverse event” is an undesirable outcome related to the provision of healthcare. It may be a natural consequence of the underlying illness, or it could be related to a treatment provided. The use of the term “event” is deliberate, as it does not imply a cause: it is simply associated with an intervention. The term “adverse reaction,” or more specifically “adverse drug reaction,” is used where a causal relationship is strongly suspected. Not all adverse events can be be causally linked to health interventions. Consequently, many adverse events associated with drug treatments can only be considered “suspected” adverse drug reactions until more information emerges to suggest the relationship is likely to be true.
Correlation fallacies can be hard to identify, even for health professionals. You take a drug (or, say, are given a vaccine). Soon after, some event occurs. Was the event caused by the treatment? It’s one of the most common questions I receive: “Does drug ‘X’ cause reaction ‘Y’?” We know correlation doesn’t equal causation. But we can do better than dismissing the relationship as anecdotal, as it could be real. Consider an adverse event that is a believed to be related to drug therapy: (more…)
Critics of mainstream medicine often point to the dangers of drugs. I previously wrote about “Death by Medicine,” where I explained the fallacy of fixating on harmful effects of drugs without putting them into perspective with all the good drugs do. Yes, patients have died from severe allergic reactions to penicillin, but penicillin has also saved countless lives.
A recent article in The New England Journal of Medicine looks at emergency hospitalizations for adverse drug events in elderly Americans. It confirms that adverse reactions are a serious problem, but some of its findings are surprising.
Working in pharmacies where supplements are sold alongside traditional (over-the-counter) medications, I’m regularly astonished at the different perceptions consumers can have about the relative efficacy and safety of different types of products. Once, speaking with a customer about a medical condition she wanted to treat, I indicated that there were no effective non-prescription therapies — she needed to see a physician for access to an effective treatment by prescription — and I gestured behind the counter. “Back there?!” she pointed. “That’s where you keep the stuff that kills people! I want something natural!” Suggesting that my patients with heart disease or HIV had a somewhat different perspective, I tried (unsuccessfully) to talk her out of a questionable-looking supplement (Hint: avoid anything from a company with a P.O. box as a mailing address.) This appeal to nature, combined with a perception that natural products are safe, and conventional drugs are unsafe, is pervasive. (more…)