While multiple pain management methods exist, doctors usually adopt the one with the most effective potential in each case. They account for the nature of pain and the individual’s variables — from pain tolerance to physiological and psychological responses. Since pain has a psychological factor attached to how the brain or mind registers and reacts to physical sensations, doctors also try to employ the power of the human psyche to relieve suffering. Pain management through the phenomenon of placebo analgesia — when a person experiences a reduction in pain after receiving a treatment with no therapeutic effect — majorly harps on the person’s trust or faith in its efficacy. It is frequently used in clinical settings, complementing conventional treatments to produce better results. It also finds use in research to evaluate the efficacy of novel pain treatments, opening new possibilities for pain management.
What is placebo analgesia?
According to Hansal Bhachech, chief, department of psychiatry, HCG Multispeciality Hospital, Ahmedabad, Gujrat, since the pain one experiences is related to the mind, their belief can impact their perception. “My perception of pain may be badly impacted if I fear it is uncurable and will last forever. However, if someone views pain as a sign of a health concern and is motivated to find out the cause and take action to address it, they will experience less of it throughout the action as they believe in the treatment.”
Though faith or belief has a huge role, other neurological processes also contribute to placebo analgesia. Dr Shubha Subramanian, a consultant neurologist at Kauvery Hospitals, Chennai, calls placebo analgesia a complex psycho-neurobiological event that involves both the central nervous system as well as the peripheral physiological mechanisms. Both can influence pain perception and clinical symptoms, modulating the response to active analgesics (substances or medications which reduce the sense of pain and inflammation by acting on peripheral tissues and the central nervous system).
Neurobiological factors behind placebo analgesia
In addition to psychological elements, neurobiological factors may impact placebo analgesia.
“The placebo analgesia is mediated by endogenous neuromodulators (chemicals that modulate or alter the activity of neurons in the nervous system) like dopamine, serotonin, and cannabinoids. These can be released due to the psychological response,” says Dr Subramanian.
Different neuromodulators can have varied effects on the brain. Dopamine is linked to pleasure and reward, and its release might strengthen people’s belief that a placebo treatment works. Serotonin also influences how we experience and interpret pain. Placebo treatments can also impact serotonin levels, affecting how pain is processed. The body also makes cannabinoids, which can alter how painful stimuli are perceived.
Understanding differential effects
Placebo analgesia can cause different reactions in individuals. In addition, some people might not get the desired result. “There may be no effects, a certain amount of pain reduction, or total pain relief. The outcomes depend on many variables,” explains Dr Bhachech.
Psychosocial variables: Psychosocial factors among individuals can affect how receptive they are to placebos.
“Their reaction to the placebo can be influenced by factors like their mental state, level of optimism, and coping strategy,” says Dr Subramanian. “Characteristics like resilience, agreeableness, good mechanisms for coping with stress, and a positive mindset, among others, can favourably alter their response to placebo through enhanced endogenous opioid secretion (body’s natural production and release of opioid compounds, which are involved in pain relief, mood control, and the stress response).”
Genetic predisposition: Some people have a higher propensity to acquire certain traits or characteristics because of genetic variants inherited from their parents. As a result, some genomes may respond well to placebo analgesia while others may not.
Brain anatomy: Since cognitive and emotional processing areas are involved in anticipating and perceiving pain reduction from placebos, those with well-developed cognitive and emotional processing areas frequently display larger placebo effects in pain alleviation. “Anatomical components of the brain, like the prefrontal cortex and the anterior cingulate cortex (brain regions), are essential in controlling placebo analgesic responses,” says Dr Subramanian.Â
Is it ethical to use placebo analgesia?
Informing the patient that they are receiving a placebo for their pain can have a detrimental impact on their trust in the treatment. In turn, it can affect their response to the placebo. This leads to the rise of ethical concerns regarding the use of placebo analgesia in clinical contexts.
According to a research paper published in Contemporary Clinical Trials, when scientifically required, certain situations outlined by ethical analysis and international ethical guidance allow the use of placebo controls in randomised trials. These include the study of conditions with no known effective treatment, situations when participants’ risks from withholding treatment are minimal or when using a placebo has strong methodological justifications and withholding treatment does not put individuals at substantial risk of harm.
Takeaways
- Placebo analgesia occurs when a patient experiences pain relief after receiving treatment with no actual therapeutic benefit. Instead, it is effective because the patient believes in the treatment’s efficacy.
- When a person’s belief system is a significant factor in the mechanism underlying placebo analgesia, endogenous neuromodulators also play a role.
- One’s response to placebo treatments can vary depending on psychosocial components, genetic disposition, and brain structure.
