There are limits to even the strongest placebo effect. No simulation could set a broken arm, of course, or clear a blocked artery. As a rule, placebos appear to affect symptoms rather than underlying diseases--although sometimes, as in the case of depression or irritable bowel syndrome, there’s no meaningful distinction between the two. Moreover, placebos have often received undue credit for recovery that might have occurred anyway. Indeed, the effect is famously difficult to identify, measure, and even coherently define. There is debate about the magnitude of the response, with some calling it modest at best, and opposing the idea of using placebos clinically.

“In the last 10 years we’ve made tremendous strides in demonstrating the biological veracity of the placebo effect,” says Ted Kaptchuk, an associate professor at Harvard Medical School and one of the coauthors of the Lancet article. “The frontier is, how do we utilize what is clearly an important phenomenon in a way that’s consistent with patient-practitioner trust, and informed consent?”

But any attempt to harness the placebo effect immediately runs into thorny ethical and practical dilemmas. To present a dummy pill as real medicine would be, by most standards, to lie. To prescribe one openly, however, would risk undermining the effect. And even if these issues were resolved, the whole idea still might sound a little shady--offering bogus pills or procedures could seem, from the patient’s perspective, hard to distinguish from skimping on care.

In February, an important paper was published in the British medical journal the Lancet, reviewing the discoveries about the placebo effect and cautiously probing its potential for use by doctors. In December, the Michael J. Fox Foundation announced plans for two projects to study the promise of placebo in treating Parkinson’s. Even the federal government has taken an interest, funding relevant research in recent years.

But as evidence of the effect’s power mounts, members of the medical community are increasingly asking an intriguing question: if the placebo effect can help patients, shouldn’t we start putting it to work? In certain ways, placebos are ideal drugs: they typically have no side effects and are essentially free. And in recent years, research has confirmed that they can bring about genuine improvements in a number of conditions. An active conversation is now under way in leading medical journals, as bioethicists and researchers explore how to give people the real benefits of pretend treatment.

In a health care industry fueled by ever newer and more dazzling cures, this phenomenon is usually seen as background noise, or even as something of an annoyance. For drug companies, the placebo effect can pose an obstacle to profits--if their medications fail to outperform placebos in clinical trials, they won’t get approved by the FDA. Patients who benefit from placebos might understandably wonder if the healing isn’t somehow false, too.

You’re not likely to hear about this from your doctor, but fake medical treatment can work amazingly well. For a range of ailments, from pain and nausea to depression and Parkinson’s disease, placebos--whether sugar pills, saline injections, or sham surgery--have often produced results that rival those of standard therapies.

In the last decade-plus, however, the accumulating data have sparked a renewed interest in the placebo as a treatment in its own right. Numerous studies have shown that it can trigger verifiable changes in the body. Brain scans have shown that placebo pain relief is not only subjectively experienced, but that in many cases the brain releases its own internal painkillers, known as endogenous opioids. (This placebo effect can even be reversed by the opioid-blocker naloxone.) Another study, published in Science in 2009, found that patients given a topical cream for arm pain showed much less pain-related activity in the spinal cord when told it was a powerful painkiller. A 2009 study found that patients benefited as much from a fake version of a popular spinal surgery as they did from the real one; asthma patients have shown strong responses to a mock inhaler.

As sugar pills were losing their place in the physician’s arsenal, they assumed a different role: as a neutral placeholder in drug testing. This development is usually traced back to a 1955 paper by Henry Beecher, a Harvard anesthesiologist who argued that the placebo effect was so potent that researchers needed to account for it when testing new drugs. Today, the “gold standard” of medical testing is the randomized clinical trial, in which the new drug must beat a placebo to prove its worth.

But in the postwar era, the profession changed in a way that relegated placebos to the shadows. New medicines began to emerge that actually cured diseases. At the same time, the longstanding paternalism of doctors was yielding to a new ethos that respected the patient’s right to understand and consent to treatment. Gradually, fake pills began to seem less like a benign last resort, and more like a breach of trust. To be sure, some doctors continued to use placebos--typically, “impure” placebos such as vitamins that had no specific effect on the malady in question. But they did so quietly, knowing the practice was frowned upon.

Phony treatment is hardly a novel concept in medicine. The word “placebo”--Latin for “I shall please”--has been used in a medical context since at least the late 1700s, referring to inert treatments given to placate patients. Arguably, until the scientific breakthroughs of the 20th century, medical history was little more than one long series of placebos.

But according to advocates, there’s enough data for doctors to start thinking of the placebo effect not as the opposite of medicine, but as a tool they can use in an evidence-based, conscientious manner. Broadly speaking, it seems sensible to make every effort to enlist the body’s own ability to heal itself--which is what, at bottom, placebos seem to do. And as researchers examine it more closely, the placebo is having another effect as well: it is revealing a great deal about the subtle and unexpected influences that medical care, as opposed to the medicine itself, has on patients.

This is just one study, but the implications could be profound. It suggests that in some cases doctors could essentially dilute medications, perhaps dramatically, and get the same results. Robert Ader, the study’s lead author and a psychiatry professor at the University of Rochester, says this approach has the potential to address maladies that operate through the nervous systems, such as pain, some auto-immune diseases, and hypertension. Ader envisions a future in which a physician writes a prescription consisting of the drug, the dosage, and the “reinforcement schedule.” Under a reinforcement schedule of 80 percent, the patient would get a bottle of 100 pills, 20 of which were dummies.

A second approach may be to integrate placebos with real treatments, and to reconsider whether this should still be viewed as fakery. A groundbreaking study published in February in the journal Psychosomatic Medicine found that in one group, psoriasis patients who received a topical cream treatment, alternated with placebo “reinforcements,” did as well as patients who got up to four times more of the active drug. The authors hypothesized that the effect was due primarily to conditioning--the brain learned to associate the cream with healing and sent the same signals even when the cream was inert.

One audacious tack would be to tell the truth: to notify patients that they are about to be given a fake pill. The idea sounds absurd, and doctors have long assumed that would ruin the effect. But there’s almost no research on the question, and it may not be as unthinkable as it seems. One reason it could work involves “classical conditioning”--the notion that we can learn on a subconscious level, like Pavlov’s dogs, to biologically respond to certain stimuli. This concept suggests that the brain could automatically react to the placebo in a way that doesn’t require conscious faith in the drug. (The placebo effect has been observed in rodents, which bolsters this theory.) Another reason is that, according to many researchers, the trappings of medical care contribute to the response. So in certain circumstances, doctors could conceivably give a placebo with total transparency, conspiring with patients to trick their own brains-- though the lack of research means there is little evidence to support this hypothesis now.

The first conundrum doctors face is how to honor the principle of informed consent, their ethical and legal obligation to fully explain a treatment. Clearly, a doctor would violate this rule by passing a sugar pill off as a real prescription drug, and thinkers have begun to wrestle with this challenge.

Impressed by such findings, some researchers and clinicians hope to import them somehow from the laboratory into the doctor’s office--adding placebo, in a systematic way, to the doctor’s repertoire.

“You’re talking about many, many, many millions of dollars a year in drug treatment costs,” says Ader. He adds, “If [doctors] can produce approximately the same therapeutic effect with less drug, then it’s obviously safer for the patient, and I can’t believe they wouldn’t want to look into doing this.”

In either scenario--prescribing ersatz medicine alone or cutting active treatment with it--it’s easy to predict the concerns and controversies that would ensue. Might cost-conscious health care providers and insurers be tempted to push placebos for financial reasons? Would patients feel cheated and confused? Whether placebos can be successfully reframed as novel medicines and helpful “reinforcements” remains to be seen.

For other researchers, the data have led to very different territory: They’re looking for ways to elicit the placebo effect while jettisoning the placebo altogether.

Some researchers argue that the real source of a placebo’s effect is the medical care that goes along with it--that the practice of medicine exerts tangible healing influences. This notion has received support from experiments known as “open-hidden” studies. Fabrizio Benedetti, a professor at the University of Turin Medical School, has conducted a number of these, in which patients receive painkiller either unknowingly (they are connected to a machine that delivers it covertly) or in an open fashion (the doctor is present, and announces that relief is imminent). Patients in the “open” group need significantly less of the drug to attain the same outcome. In other words, a big part of the effect comes from the interactions and expectation surrounding the drug. Some call the disparity between the two scenarios the placebo effect. (Others, however, say the word “placebo” should be reserved for inert treatments, and press for different terms, such as “meaning response” or “context effect.”)

“Medicine is intensely meaningful,” says Daniel Moerman, a professor emeritus of anthropology at the University of Michigan at Dearborn who coined the phrase “meaning response.” “It’s this highly stylized, highly ritualized thing.” He urges us to “forget about the stupid placebo and start looking at the system of meaning involved.”

A recent study by Harvard’s Kaptchuk suggests the importance of ritual and the doctor-patient relationship. A 2008 paper published in the British Medical Journal described experiments conducted on patients with irritable bowel syndrome. Two groups underwent sham acupuncture, while a third remained on a waiting list. The patients receiving the sham treatment were divided into two subgroups, one of which was treated in a friendly, empathetic way and another with whom the doctors were businesslike. None of the three groups had received “real” treatment, yet they reported sharply different results. After three weeks, 28 percent of patients on the waiting list reported “adequate relief,” compared with 44 percent in the group treated impersonally, and fully 62 percent in the group with caring doctors. This last figure is comparable to rates of improvement from a drug now commonly taken for the illness, without the drug’s potentially severe side effects.

“It’s amazing,” says Kaptchuk. “Connecting with the patient, rapport, empathy . . . that few extra minutes is not just icing on the cake. It has biology.”

It may be, then, that the simplest and least ethically hazardous way to capitalize on the placebo effect is to acknowledge that medicine isn’t just a set of approved treatments--it’s also a ritual, with symbolism and meaning that are key to its efficacy. At its best, that ritual spurs positive expectations, sparks associations with past healing experiences, and eases distress in ways that can alleviate suffering. These meanings, researchers say, are what the placebo effect is really about.

If this is true, then the takeaway is not necessarily that we should be dispensing more fake pills--it’s that we should think less about any pill and more about the context in which it’s given. Whether we call it the placebo effect or use new terms, the research in this field could start to put a measurable healing value on doctors’ time and even demeanor, rather than just on procedures and pills. And that could change medicine in a way that few blockbuster drugs ever could.

Rebecca Tuhus-Dubrow is a contributing writer for Ideas. She can be reached at rebecca.tuhusdubrow@gmail.com

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