Placebo Vs. Nocebo Effect: When your mind makes you sick
by James Hubbard, M.D., M.P.H.
Patients need to be informed. That’s what my blog and magazine are all about. But sometimes, how you think about that information can physically affect you.
The placebo effect, or placebo response, has been known for years. A placebo is a treatment that has no active ingredients–no logical reason to have any effect, a sugar pill. The placebo effect is when this inactive treatment provides active results. For instance, placebo has helped alleviate pain, lower blood pressure; the list could go on. That’s why the best medical studies compare the active treatment to placebo (placebo-controlled).
It can happen to anyone, and I see it frequently. If someone thinks a treatment will cause an effect, it can. There are loads of studies, some showing actually physiological changes in the body–the power of positive thinking, mind over matter.
But what happens when the opposite effect occurs?
When adverse symptoms are the result of an inactive treatment, it’s caused the nocebo effect. Just read the full disclosure package insert attached to bottles of medication. Side effects that can happen when you take the drug are listed, along with side effects of people in studies who took the placebo.
If drowsiness occurs in 20 percent of people taking the treatment, and 19 percent of those on placebo, then really, the drug causes drowsiness in only 1 percent. Or does it? The drowsiness is real to all, or most.
So what can you do to keep this from happening to you? Richard Krandin, M.D., author of The Placebo Response and the Power of Unconscious Healing, gives some tips below.
Has anyone had experiences with placebo or nocebo responses?
Seven Ways Your Mind Can Make You Sick
by Richard Kradin, M.D.
Your beliefs can make you sick. Doctors have long known about this phenomenon, called the nocebo effect. The nocebo effect is the opposite of the placebo effect. It happens when, for instance, a patient is given a harmless treatment, such as a sugar pill, believes there will be a negative side effect, and then actually experiences the side effect.
Here are seven ways your beliefs, doubts, and fears can produce unpleasant symptoms of illness or slow down the healing process.
- Making assumptions based on appearance. Studies show that people believe small pills are less effective than large ones, red pills cause more side effects than blue, generic are less effective than brand-name drugs, and oral medication is less potent than injected medication.
- Having too much information. When patients read and learn about all the side effects from a drug insert in distressing detail, they are more likely to experience those symptoms than patients who were unaware of the side effects.
- Believing misinformation. So many people believe penicillin allergies are commonplace that a statistically impossible percentage of patients (10 percent) experience symptoms of penicillin allergies, even though less than 3 percent of adults are actually allergic.
- Scary language. The language adopted to describe side effects of a drug can greatly influence expectancies and outcomes. In one study, instructing subjects to “look for evidence of nasal obstruction” evoked more upper airway symptoms than instructing them to “pay attention to the free passage of air.”
- Incidental environmental cues. Conditional nausea occurs in a full one third of chemotherapy patients and may be triggered by incidental environmental cues, like being in a treatment room the same the color as the last one where a patient felt sick.
- Fearing the worst. In the Framingham Heart Study, women who feared they were at risk for heart disease were nearly four times more likely to die than women with similar risk factors–obesity, and high levels of cholesterol and blood pressure–who didn’t.
- Hearing the worst. When physicians offer a pessimistic answer to the question, “What can I expect, Doc?” the patient’s healing process may sometimes slow down or stop.
Dr. Kradin practices medicine at Massachusetts General Hospital and is an associate professor at Harvard Medical School. He is trained in internal medicine, pathology, immunology, and psychoanalysis.
Tags: strange and surprising









September 15th, 2008 at 12:31 pm
That is pretty interesting. The mind is a powerful thing. Think good thoughts!
Blakes last blog post..Walking for Fun?
September 15th, 2008 at 1:57 pm
Thanks Blake, I like your post, “why positive thinking is important”. The way you think really can make a difference.
September 15th, 2008 at 3:44 pm
Really great blog post. It’s good to see that mainstream medicine is acknowledging how powerful the mind can be in shaping health, both positively and negatively. It’s so important to become aware of not only placebo/nocebo effects, but also how you think about yourself/health/body on a day to day basis. Another book your readers might want to check out is: Your Body Believes Every Word You Say.
September 15th, 2008 at 4:45 pm
Thanks for the info, Vanessa. It helps to be around positive people also.