What is the Placebo Effect?
The placebo effect occurs when a fake medical treatment produces real medical benefits psychosomatically. In short, believing in the treatment and the power of the mind can help someone feel better. The placebo effect can be so powerful that it mimics genuine medicine. Consequently, scientists need to control for it when conducting clinical trials.
Originating from Latin, “placebo” translates to “I will please.” It describes treatments that seem genuine but lack healing properties. Whether it’s a sugar pill, a saline injection, or a non-medicinal liquid, it’s all about appearances.
Thousands of studies have shown placebo effects in action for numerous conditions, including the following examples:
- Chronic pain
- Arthritis
- Migraines
- Nausea
- Fatigue
- Irritable bowel syndrome
- Sleep conditions
- Depression and other mood disorders
Placebo effects tend to be the strongest for self-reported symptoms of how people feel, such as those in the list above. The placebo effect helps patients feel better but doesn’t treat the underlying condition.
National surveys reveal that many doctors prescribe placebos regularly because of their powerful effects. For instance, 77% of general practitioners in the UK admit to prescribing them weekly. Usually, the person receiving the placebo believes it is actual medicine, boosting the effect. However, some research has suggested that patients can still gain some benefits even when they know they’re taking placebos. When doctors prescribe placebos to their patients without secrecy, they call them “honest” or “open-label” placebos.
Learn more about Effect Sizes in Statistics.
How the Placebo Effect Works
What ignites the placebo effect? The individual’s faith in the treatment and their anticipation of improvement, not the placebo’s inherent qualities, triggers genuine physical and psychological responses in the body. It is a complex phenomenon with several underlying psychological and neurobiological mechanisms.
Some known factors can heighten the placebo effect. These include:
- Placebo Presentation: The placebo’s appearance matters. Real-looking pills increase belief in their potency. Interestingly, research indicates that larger pills are more effective than smaller ones. Taking multiple pills amplifies this belief. Additionally, injections typically elicit a stronger placebo effect than pills.
- Patient’s Mindset: Expectations play a role. If a patient anticipates positive results, the placebo effect is magnified. Yet, the effect can still emerge even among skeptics, underscoring the subtle power of suggestion.
- Trust in Healthcare: A strong doctor-patient bond boosts the placebo effect. If patients trust their healthcare provider, the placebo’s efficacy rises.
How the placebo effect precisely works in the mind remains a mystery. However, several theories aim to shed light on it.
Conditioning
Past experiences shape our responses. If someone felt better after a treatment previously, a placebo might elicit a similar beneficial response thanks to our conditioned response mechanism. For instance, if you regularly take a pill for pain control, you’ll start to associated pain reduction with taking a pill. When you take a placebo, you’re already conditioned to expect pain reduction.
Studies also hint that the brain reacts similarly to real and imagined scenarios. A placebo might activate memories of pre-symptom health, a concept termed ‘remembered wellness.’
Expectations
Our mindset is powerful. Simply anticipating positive outcomes from a treatment can lead to actual improvements. The brain can manifest wellness based on sheer belief. For example, imagine a doctor excitedly prescribes a new migraine medication. Her enthusiasm for the treatment can impact how you respond to it. Even if the new “treatment” is a sugar pill, the doctor’s excitement can prompt the placebo effect.
Brain Chemistry
Brain chemistry plays a part in the placebo effect. Some studies suggest that just taking a placebo can release endorphins, acting like natural painkillers. These chemicals can boost mood and alleviate discomfort.
Studies have used brain scans to associate the placebo effect with brain areas that contain numerous opiate receptors. Natural endorphins bind to these receptors to reduce pain. Other studies have found that Naloxone, which blocks opioids and natural endorphins, reduced the placebo effect’s pain relief abilities.
The Role of the Placebo Effect in Clinical Studies
Medical treatments must be more effective than placebos before approval. With the potent nature of the placebo effect, how do clinical trials ensure that the observed benefits of a new treatment aren’t just the placebo effect? After all, there’s no reason to risk using active medication with potential side effects if a sugar pill works just as well.
Consequently, it’s crucial to compare the medication’s effect to the placebo effect. Enter randomized controlled trials with a placebo control group.
Randomized Controlled Trials (RCTs) are the gold standard in clinical research. They aim to determine the efficacy of a new treatment or intervention Frequently, RCTs include a control group receiving a placebo rather than receiving no treatment. This practice provides a baseline for comparison. Analysts can compare the treatment group directly to the placebo control group. Learn more about the Types of Control Groups in Experiments.
For researchers to conclude that the treatment is effective beyond the placebo effect, the difference between the treatment and placebo groups must be statistically significant. If both groups are similar, you can’t rule out the placebo effect.
By accounting for the placebo effect, RCTs ensure that new treatments provide actual, tangible benefits beyond what our minds can conjure. It’s about ensuring genuine medicinal efficacy.
Learn more about Randomized Controlled Trials (RCTs).
Nocebo Effects
Not all placebo effects are beneficial. Indeed, doctors use the term “nocebo effect,” derived from the Latin nocere meaning “harm,” when a placebo causes undesirable outcomes. RCTs can uncover these effects as well.
For instance, a study published in JAMA found that the nocebo effect produces most of the side effects in COVID-19 clinical trials. In these RCTs, control subjects receive saline injections for the placebo. The results indicate the nocebo effect accounts for 76% of the fever, headache, and fatigue symptoms associated with the vaccinations.
I guess if you worry about side effects, you’ll likely experience them! These findings suggest that anxiety and expectation are frequently behind those symptoms rather than the COVID shots themselves.
Read my review of a COVID-19 Vaccine Clinical Trial.
Wrapping Up the Placebo Puzzle
Our exploration into the placebo effect underscores a profound truth: the human brain possesses an incredible power to influence our well-being. The power of the mind can help us feel better . . . or worse.
For researchers, this means a meticulous journey in clinical trials, ensuring that treatments aren’t just tapping into this mind-driven phenomenon but are genuinely effective. By accounting for the placebo effect, science acknowledges the dance between body and mind, ensuring discoveries are genuinely beneficial.
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