The Chronic Pain Experience

The Chronic Pain Experience

Anyone who suffers from chronic pain knows how difficult it is to lead a normal life. Recent medical research has indicated that chronic pain is more than a physical disorder in the back, a hip or a knee. Continuing pain signals from the site of pain (the pain generator) lead to central nervous system changes. These changes are like “short-circuits” that can worsen the intensity of pain experienced even if the pain signal from the pain generator decreases. So although the pain began acutely in a knee, low back, or other site, over time the changes in the central nervous system create additional pain, which is added above and beyond the pain from the original pain generator. This combination of pain from the pain generator and the central nervous system changes is called the chronic pain experience (CPE). It is important to understand that the CPE is real pain. The science demonstrating changes in the brain and central nervous system with chronic pain does not mean the chronic pain is “in your head”, which implies exaggeration or faking. The CPE is your real subjective experience and cannot be questioned. If your pain number is a 10/10, then 10/10 is the real level of your CPE.

The CPE also includes psychological, emotional and behavioral changes resulting from the central nervous system changes. Your ability to perform your job and day-to-day tasks is challenged, decreased, or at worst given up. Your personal relationships often suffer because of the mental and emotional changes resulting from the CPE.

Tragically the CPE is even more insidious. The CPE consequences mentioned above occur on top of pre-existing stressors you may have had before you developed chronic pain. These vulnerabilities or stressors have been demonstrated in research to worsen the CPE.  These vulnerabilities can be grouped in two categories, Psychosocial Wellness (PW) and Behavioral Health Sensitivity (BHS).  The factors were present in your life prior to the onset of your chronic pain and have been shown to color the CPE.

Your level of PW involves:

• Your level of satisfaction with your employment, vocation or educational pursuits

• Your level of satisfaction with support system, including family, friends and social groups

Your BHS is a neurologic profile resulting from a combination of risk factors and life experiences.

These BHS factors include:

• family history of a mental health disorder such as depression or anxiety

• family history of a substance use disorder

• personal history of a mental health or substance use disorder (even if many years ago)

• personal history of abuse, neglect, trauma or chaos (called Adverse Childhood Events)

Research indicates that more BHS risk factors one has the more severe the CPE is likely to be. These factors contribute to the downward spiral of ‘suffering’ of the CPE.

Chronic Pain and Traditional Opioids

One of the most widely used methods of chronic pain management is the use opioid medications. Traditional opioids such as hydrocodone, oxycodone, morphine, codeine and other related painkillers are very effective at immediately controlling and eliminating acute pain. However there are risks and pitfalls to using traditional opioid painkillers for long-term management of chronic pain. The traditional opioids often lose their initial profound pain relieving properties over time, leading to increases in the dose and addition of other controlled ("controlled" drugs are those that are monitored by the Drug Enforcement Agency, the DEA, because the have a risk of addiction associated with their use) medications such as benzodiazepines (Valium, Ativan or Xanax). Dose increases in traditional opioids can lead to side effects such as constipation, sedation, decreased sexual functioning, impaired immune system functioning and a decrease in respiratory functioning that can be fatal. 

More insidious there are gradual and sometimes unnoticed side-effects that may occur in the central nervous system of persons taking traditional opioids. 

Gradual and often missed side effects of traditional opioids used for chronic pain include:

Decreased cognitive functioning in areas of attention, concentration, planning and impulse control

• Emotional changes including depression, anxiety, anger or mood swings

• A loss of joy from naturally rewarding experiences (anhedonia)

• An increase in the stress response (fight/flight) system

These side effects of traditional opioids are often not recognized in the person taking the opioids because the symptoms of disconnection from life, mood changes, anger, anxiety or a lack of joy may be attributed to the chronic pain itself, or the life changes caused by the pain.  Of course it is true that chronic pain can contribute to central nervous system changes causing behavioral, psychological and emotional symptoms mentioned above.  However the research is clear that traditional opioids can worsen these pain-induced brain changes and increase the suffering of the chronic pain experience.

A new medication for the chronic pain experience

In the past chronic pain sufferers have had few choices when it comes to potent medication-based pain management. Recently, however, the FDA-approved drug buprenorphine has been used with considerable success in chronic pain. Buprenorphine is a powerful opioid pain relieving medication with special pharmacologic properties that make it safer than the traditional opioids used in pain management. It has a ceiling effect on respiratory depression which means that used at normal pain management doses it does not have the overdose mortality risk seen with other opioids. It is also has a ceiling effect on the reinforcing properties making it less likely to inadvertently lead to misuse, abuse or an opioid use disorder (previously called opioid addiction). Buprenorphine was initially derived from the naturally occurring opium poppy derivative thebaine.  It was chemically modified by pharmaceutical researchers over 30 years ago and found to have excellent pain relieving properties with the lower risk profile mentioned above. 

Buprenorphine has been successfully used as a powerful post-operative pain reliever for more than 40 years in Europe

Confusion about buprenorphine exists in the United States because it was FDA approved and marketed in the early 2000’s to treat opioid use disorder. Many physicians in the US have never used buprenorphine for pain and are unaware of its robust pain-relieving/analgesic effects. There is a great deal of misinformation in the lay and medical press about buprenorphine having a limited pain-relieving profile. This is due in part to misinterpreting the data on buprenorphine’s ceiling effects on respiratory depression and reinforcing effects. There is, in fact, no ceiling on buprenorphine’s pain-relieving effect when used in the appropriate dose range.

The excellent pain relieving properties combined with its reduced risk profile make buprenorphine a valuable tool in the management of the Chronic Pain Experience.

Buprenorphine comes in two under-the-tongue or sublingual forms: Subutex, which is composed of only buprenorphine, and Suboxone, which is a combination of buprenorphine and naloxone (both FDA approved in US for opioid use disorder [OUD]). There are also forms that can be placed on the inside of the cheek (Belbuca- FDA approved in US for chronic pain) and a patch worn on the arm (Butrans- FDA approved in US for chronic pain). 

If buprenorphine is used for OUD the prescriber must have several hours of training in using buprenorphine in OUD. Any licensed prescriber can prescribe buprenorphine for pain without a special license.

The choice of form of buprenorphine depends on a number of factors that you should discuss with your pain management team. 

What is Buprenorphine?

Buprenorphine is an "agonist-antagonist" at the opioid receptor in the brain where morphine and other traditional opioids bind. The term "agonist-antagonist" is used by pharmacologists to describe its unique properties. This term describes the unique property of buprenorphine that when it is used in its appropriate dose range. At the right dose it activates or turns on (is an "agonist") the opioid receptor, bringing pain relief and other opioid effects. However when used at doses above its appropriate dose range (at doses that could lead to respiratory depression and death with traditional opioids),  it stops this activating or turning on effect and becomes an "antagonist" and turns off the over-stimulation of the receptor.  This is why buprenorphine has a reduced risk profile compared to other traditional opioids that don’t have this unique property. 

Because buprenorphine is a risk-reduced  agonist-antagoist opioid that works powerfully at the opioid receptor to block pain, it can be an attractive option for long-term chronic pain management. 

Compared to traditional opioid painkillers, long-term use of buprenorphine has a lower risk of side effects, physical dependency and milder withdrawal symptoms when usage ends. Even with these benefits, there are some risks to using buprenorphine, and because it is an opioid it should only be taken under the supervision of a trained medical professional. Overdosing or taking buprenorphine with alcohol, sedatives or CNS depressants can lead to severe complications that include disability and death.

Using buprenorphine has its advantages when compared to other opioids, but using any medication alone is not an effective treatment for chronic pain. Managing chronic pain should include more than just medication; it should also include non-medication based treatments to address the psychological, emotional and social components of chronic pain. This is the type of comprehensive multi-modal pain management program offered at REMI.

Why change your opioid to buprenorphine?

Many patients are disappointed to see that as time goes on their traditional opioid medicines are less and less effective in treating their pain. This is because, over time, the central nervous system adjusts and changes. This results in less pain relief and more side effects as the dose of the opioid is increased chasing an ever-moving target of pain relief. Eventually one can no longer take enough pain medication to control their pain. Since they are no longer getting pain relief, the only reason they continue to take the pain medication is to prevent a perceived worsening of pain or to prevent going into withdrawals from stopping the opioid. By changing the opioid to buprenorphine the central nervous system changes caused by chronic pain and long-term traditional opioid use are given an opportunity to return to a more normal situation of functioning.  This provides an opportunity for one to engage and respond optimally in a comprehensive multi-modal pain management program.