Besides painkillers, what other methods can we use to relieve pain?

Produced by: Science Popularization China

Author: Clover Aoko (Doctor of Medicine)

Producer: China Science Expo

Gut microbes linked to endometriosis pain

(Image credit: Daniel Stolle for Nature)

Pain is an inevitable part of life. From headaches and muscle aches to the sting of an accidental burn, everyone has to fight pain. When facing pain, most of us rely on painkillers, such as ibuprofen and acetaminophen, but many people worry that long-term use of painkillers will lead to dependence or side effects. Is this really the case? This is closely related to the principle of painkillers.

Are there other ways to relieve pain besides painkillers?

In recent years, scientists and doctors have been exploring non-drug pain relief methods, from traditional physical therapy to cutting-edge psychological interventions, and even virtual reality has shown unexpected results. How can these therapies help us? Today, let us learn about these pain management methods that may not be familiar but are full of potential.

Painkillers are the most popular choice for pain relief

Before discussing non-drug treatments, let’s first look at the pain relief options that most people are familiar with: medications. Painkillers help us deal with a variety of discomforts from headaches to injuries, but when choosing, different types of drugs have different ingredients, mechanisms of action, and risks.

Pain relievers are broadly divided into two categories: anti-inflammatory analgesics and opioids.

Anti-inflammatory analgesics (such as acetaminophen, aspirin, and ibuprofen) relieve pain by reducing inflammation in the painful area. They are generally safe, but excessive or long-term use may damage the liver and kidneys and even cause gastrointestinal discomfort. Most of these drugs are over-the-counter. Opioids (such as codeine, fentanyl, and hydrocodone) relieve pain by changing the brain's perception of pain. They have powerful analgesic effects, but the side effects are also strong and usually require a doctor's prescription.

Over time, some painkillers can cause tolerance, requiring higher doses to achieve the same effect. Drug addiction means that patients become dependent on drugs and experience withdrawal symptoms when they stop taking them, so they cannot stop taking them even though they know it is harmful to their health.

Addiction and tolerance manifest themselves differently among different types of painkillers.

Anti-inflammatory analgesics generally do not cause tolerance or addiction because they do not affect the brain's reward system and do not cause withdrawal symptoms after discontinuation of the drug. However, for some patients with chronic diseases, long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen) may lead to a decrease in the effectiveness of the drugs.

In contrast, opioids are prone to drug resistance . The longer they are used, the greater the dosage required. They also activate the brain's reward system, bringing a sense of pleasure, which can easily lead to addiction, and withdrawal symptoms are often associated with discontinuation of the drug. China's strict control requires that opioids in China must be obtained with a doctor's prescription. However, the behavior of Purdue Pharma, which used strong marketing to push the opioid "OxyContin" to the market, still exists, which is worthy of vigilance.

OxyContin pain reliever

(Photo source: Phoenix.com)

There is no right or wrong in medicine itself, the key is to use it properly . Correct use of painkillers does not bring risks, and abuse is the root cause of addiction and side effects. As long as you strictly follow the doctor's advice and take it according to the instructions, you don't have to be afraid of painkillers.

Inspiration from intestinal microbes

Many people rely on painkillers to relieve pain, however, for some stubborn chronic pain, the effect of painkillers is often limited. Scientists have turned their attention to intestinal microorganisms and found that these tiny "intestinal residents" may play a key role in the regulation of chronic pain.

Two decades ago, irritable bowel syndrome (IBS) was first discovered. IBS is characterized by visceral pain that originates from organs in the abdomen and pelvis. Animal studies have found that certain bacteria in the intestines stimulate pain receptors on intestinal cells in a manner similar to morphine, directly affecting the perception of pain.

In 2008, further research found that animals with intestinal flora imbalance due to stress had significantly increased sensitivity to visceral pain, and probiotic trials also showed a slight but significant pain relief effect on IBS patients. Chemicals produced by intestinal bacteria can promote or inhibit pain, such as short-chain fatty acids that stimulate immune cells to release pro-inflammatory factors, and bile acids that inhibit the activity of sensory nerves.

Microglia (green) in the spinal cords of mice with endometriosis can become overactive, and signals from the gut microbiota can easily travel from the gut to other pelvic organs and beyond.

(Image credit: Gabriel Luna, NRI-UCSB/Wellcome/CC BY 4.0)

Endometriosis is another type of visceral pain. Many women with endometriosis report that they have found relief from their condition by changing their diet. A survey of 2,600 women with endometriosis showed that 83% experienced a reduction in pain after adjusting their diet (e.g., gluten-free, dairy-free).

Researchers have confirmed that patients' gut microbiota are altered, and scientists are continuing to explore the specific bacterial species to better understand the role of microorganisms in pain relief.

The gut microbiome can also play a role in non-visceral chronic pain. Gut microbes not only help relieve fibromyalgia pain, but also help diagnose fibromyalgia and other chronic pain diseases. Minerbi's 2019 study showed that the gut microbiome of fibromyalgia patients was altered. He tried to transplant feces from healthy donors into fibromyalgia patients, and after treatment, most patients had reduced pain.

In addition, the research team developed algorithms to distinguish people with fibromyalgia from those without chronic pain by analyzing the gut microbiome profile and other markers, providing a new perspective for pain diagnosis.

Amir Minerbi prepares gut microbiome samples for analysis.

(Photo credit: Rambam Health Campus)

Other studies linking chronic pain to gut microbes are underway. The gut microbiome is very broad, and further research is needed to determine which strains are effective for specific types of chronic pain, or how long they last. Individual differences also make it difficult for microbial therapy to "win with one stroke." Nevertheless, as scientific exploration continues to deepen, gut microbial therapy has brought new possibilities for the management of chronic pain .

Drug-free pain relief methods are being studied

In the treatment of chronic pain , non-invasive, non-pharmacological (NINP) therapies are gradually gaining attention. It doesn't sound novel to relieve pain through yoga, virtual reality (VR), tai chi, or even meditation without relying on pills? More importantly, these methods have almost no side effects and will not cause opioid addiction. Many NINP techniques have been studied in trials as rigorous as drugs or surgery.

Acupuncture can be used to help relieve chronic pain.

(Photo credit: BSIP/UIG via Getty)

Exercise therapy is a classic choice for NINP . It is simple and easy to do and has been found to be particularly effective in relieving chronic low back pain, osteoarthritis and fibromyalgia in many studies. Whether it is Tai Chi, swimming, Pilates or yoga, finding a method you like and gradually increasing the intensity can reduce pain without you noticing. This type of therapy not only exercises the body, but also regulates pain perception.

Another method that helps relieve chronic pain is cognitive behavioral therapy (CBT) , which involves identifying and changing negative thought patterns. A British study of 4,000 patients showed that CBT was even more effective in relieving pain than some conventional methods. Nearly a quarter of patients who received CBT reported a 30% or more reduction in pain. This type of therapy not only helps patients physically, but also psychologically increases their confidence in fighting pain.

At a clinic in New Hampshire, cognitive behavioral therapy is used to treat chronic pain.

(Image credit: Dartmouth Health)

Virtual reality (VR) therapy has added a sci-fi touch to pain treatment. By wearing VR equipment, patients can instantly "travel" to a lakeside meditation, a beach walk, or even experience the freedom of flying. An app developed specifically for chronic pain combines CBT and VR. A study of patients with chronic neck and lower back pain showed that during VR sessions, patients' self-reported pain dropped by several points on a scale of 0-10.

In another VR therapy called “virtual embodiment training,” phantom limb pain patients use hand controllers to control an avatar of their own body, which helps them move their body without worrying about pain. A preliminary study of this training showed that patients experienced improvements in pain intensity, disability, and helplessness.

Virtual reality therapy can help reduce pain intensity.

(Image source: Karuna Labs Inc.)

Currently, the strength of evidence for NINP therapy is moderate or low, which means that existing research may not be comprehensive enough and has limitations such as small sample size, short time or inconsistent results. This does not mean that NINP therapy is ineffective, but there is a lack of sufficient high-quality research to verify its effectiveness. With the increase of evidence, model innovation and the need for alternatives to opioids, NINP therapy will play an increasingly important role in pain management.

We have more options for managing and relieving pain

Although drugs are an important tool for relieving pain, they also face limitations, especially in the treatment of chronic pain, where the addictiveness and tolerance of drugs discourage many patients. For this reason, microbial therapy and various NINP therapies have gradually come into people's view, from regulating intestinal flora to using yoga, cognitive behavioral therapy (CBT) and virtual reality (VR). These methods not only provide more options for pain management, but also avoid the side effects of drug dependence.

These new explorations show us that human understanding and management of pain are developing in a more diversified and personalized direction. Pain is a common occurrence in life. We don't need to be afraid of it. Instead, we can use scientific methods and a positive attitude to face it. As research continues to deepen, there will be more innovative therapies in the future to help us better manage and relieve pain, so that everyone can enjoy a better quality of life.

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