Nocebo – I shall harm

Suzanne B. Robotti
Suzanne B. Robotti Executive Director
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If a patient is told of potential negative side effects of a medicine, the patient is more likely to experience those side effects — even when given a placebo and not the medicine!  But, what is nocebo?

This is called nocebo, “I shall harm” in Latin. Placebo translates: “I shall please,” and the two are opposites in the world of medicine. Several studies have shown what common observation has told scientists for years: In many cases a sugar pill, or placebo, will have the same effect, or better, than the actual medicine. Does that mean that the illness was in the patient’s mind? Not at all. A fascinating study gave patients with diagnosed (not fake or psychosomatic) irritable bowel syndrome a sugar pill. The doctors told the patients they were getting pills made of “an inert substance, like sugar pills, that have been shown in clinical studies to produce significant improvement in IBS symptoms through mind-body self-healing processes.” Significant results were observed when reviewed at 11 days and again at 21 days. Improved were symptom severity, adequate relief and quality of life. (PLOSone via The New Yorker)

What application does this have for patients who are warned of the possibility of severe side effects? Unfortunately, the same exact outcome.  When a patient expects to experience negative side effects, they usually do in fact experience them.

There are doctors who are choosing to not tell their patients about the potential negative side effects so that those who might be suggestible won’t experience them. Dr. Dave Hepburn blogs that he encourages his patients not to read the S/E package insert. He writes: “Doctor and pharmacist have usually already taken into consideration the risk/benefit ratio.”


With respect, I disagree. First, about the assumption that the doctor and the pharmacist have somehow consulted each other and come to a reasoned decision. MDs have to know all about diagnosing and hands-on care along with medicines. Pharmacists are drug experts. Even so, does a doctor consult with the pharmacist before prescribing a medicine? Mine doesn’t. Does the pharmacist discuss the risk-benefit of a medicine already prescribed by an MD? Mine doesn’t, unless a. I initiate the conversation, or b. the pharmacist has spotted a potential conflict between two prescribed drugs. In many cases,medicines are delivered straight to the home or dispensed through the drive-through window of a pharmacy. In those and other cases, pharmacists never have personal contact with the patient.

I also disagree with Dr. Hepburn’s contention that the doctor has the ability to determine which risk of potential side effects the patient would choose. Every drug has side effects. One patient might choose the medicine that sometimes causes stomach upset knowing that he has an “iron stomach.” That same patient might not have any tolerance for headaches, which an alternative but equally effective drug might trigger. Paternalistic thinking cuts the patient out of the health care team. The patient who blindly takes a drug and has an adverse outcome is victimized a second time.

Think of this scenario: A drug is prescribed and taken, the medical issue successfully resolved. The patient slowly falls into a malaise, an unhappiness but not quite a depression. The patient has no idea that the medicine prescribed has a potential side effect of mild depression because the doctor didn’t tell him. The quality of his life has deteriorated, yet the treatment was deemed successful! If the patient had realized that the drug might be causing the sadness and reached out to his doctor, then the medicine could be switched to one that might not have that side effect. Most medical issues have several drug choices, sometimes even non medical choices. But without a trusting partnership between patient and doctor, the patient cannot be well-served and nocebo can occurs.


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