Given the analgesic effects of alcohol on pain, pervasiveness of alcohol use as a pain management strategy has proven to be substantial among individuals exhibiting pain. For example, in a study of older adult (ages 55–65) problem drinkers and healthy controls, the drinkers were more likely to report more severe pain, greater pain interference, and more frequent use of alcohol to manage pain (Brennan et al., 2005). In a recent large study (Alford et al., 2016), the investigators identified 589 adult primary care patients who screened positive for illegal drug use and misuse of prescription medications. Of those, the majority (79%) of the individuals identified self-medication for pain as the reason for heavy alcohol use. Pharmacotherapy approaches that may be effective include those that target brain reward and stress systems.
Health Conditions
Although experimental nociceptive-pain differs in many ways with clinical pain, there is evidence that the analgesic properties of alcohol may support self-medication behaviors of pain sufferers. Experimental induction of a moderate but clinically significant acute pain (capsaicin plus heat) increased the urge and intention to drink alcohol in healthy undergraduate students reporting frequent drinking experiences 52. Several studies have reported an association between moderate alcohol use and reduced pain especially in men 51, 53, 54. The hypoalgesic effects of alcohol consumption can also be observed despite the presence of chronic pain 56. Paradoxically, as discussed further below, alcohol may be an effective hypoalgesic for the short-term relief of pain but long-term consumption of alcohol results in exacerbated pain, increasing an individual’s risk towards alcohol misuse and the development of AUD 51. A majority of the previous work examining the neurobiology of alcohol has focused on the investigation of individual brain regions, although how central stress and nociceptive circuits are engaged and potentiated in the state of alcohol dependence is a rapidly developing area of preclinical research.
What does ‘moderate drinking’ mean?
While the idea of abstaining completely may feel daunting, there’s a growing cultural shift toward mindful drinking, or not drinking. Dietary Guidelines for Americans continued to recommend that men consume no more than two drinks per day and women no more than one. “A lot of people with this genetic variant are aware of some of the visible symptoms, but they don’t know that it means alcohol really puts them at more risk than other people,” Chen said. Newer studies are also uncovering how alcohol may interfere with the immune system and accelerate molecular signs of aging. The initial contact points — mouth, throat, esophagus and stomach — are most vulnerable, which is why these areas show some of the strongest links to alcohol-related cancers.
- A role of symbiotic microbes in the causal mediation of nociceptive-pain has been confirmed by the experimental construction of axenic or “germ-free” mice made free from all microorganisms by preventing natural colonization by microorganisms.
- However, new findings show that when one drinks regularly and over time, even if they are consuming alcohol “in moderation,” it is more likely that they will become more sensitive to pain, a physiological phenomena that is then exacerbated when they attempt to withdraw from alcohol.
- Similar effects of alcohol and endogenous opioids on nociceptive-pain suggest an intersection of neural circuits, more specifically the opioid-mediated regulation of GABA neurotransmission 109, 140.
- This heightened emotional state has a parallel in the pain system in the form of the transition from alcohol-induced analgesia to alcohol-induced hyperalgesia and chronic pain 109.
Moderate drinking is typically defined by public health agencies as up to one alcoholic drink per day for women and up to two for men. Factors including age, genetics, body size and existing health conditions all influence how alcohol affects a person. Stafford and his colleagues said the choice to tip back a beer or forgo alcohol — like many lifestyle decisions — should involve weighing the risks and benefits of your behaviors. But they think the public should be made more aware of those risks, which include an increased risk of cancer from drinking moderate amounts of alcohol. A critical sign of alcohol consumption becoming alcohol misuse is when someone uses alcohol to “solve a problem.” This is when alcohol consumption becomes a coping mechanism, something the person is doing to how alcohol consumption contributes to chronic pain cope with another non-optimum condition. When someone begins using alcohol in a way they believe will “numb their pain” or accomplish some other goal, that is a sign of alcohol addiction.
Health risks of alcohol use
For example, a recent study calls attention to our gaps in understanding of neuroimmune processes in the treatment of acute pain and the transition of acute pain to chronic pain. Treatment with steroidal and non-steroidal anti-inflammatory drugs for early musculoskeletal pain conditions have hypoalgesic efficacy, however early anti-inflammatory treatment interfered with a protective effect of acute inflammatory responses against the development of chronic pain in the long-term 26. In animals and humans acute alcohol consumption has hypoalgesic properties,1 but when alcohol consumption transitions to chronic consumption it hastens the progression to chronic pain a condition that is highly comorbid with alcohol misuse and Alcohol Use Disorder (AUD) 27.
Sleep and mental health: What the science says
Since previous research has shown that the immune system is activated in response to peripheral alcohol neuropathy, the researchers also examined the activation of the immune response in non-dependent mice with neuropathic pain. Chronic alcohol consumption may make people more sensitive to pain through two different molecular mechanisms — one driven by alcohol intake and one by alcohol withdrawal. That is one new conclusion by scientists at Scripps Research on the complex links between alcohol and pain. Because acetaldehyde accumulates more quickly in people with the ALDH2 variant, they are at an increased risk of alcohol-related diseases, including cancer and heart disease, even at lower levels of alcohol consumption.
Acceptance and Commitment Therapy (ACT) and Dialectical Behavior Therapy (DBT) are evidence-based approaches that incorporate mindfulness practices. ACT emphasizes building psychological flexibility and emphasizes values-congruent practices, while DBT emphasizes the development of emotional regulation and distress tolerance skills. These approaches transform our relationship with our thoughts, emotions, and physical sensations, including pain. This can change the quality of our experience in ways that change the subjective experience of pain as well as the suffering precipitated by it. It’s not unusual for people with chronic pain to consume alcohol to self-medicate—to drink to help sand down the sharp edges of their pain and turn down the volume of their discomfort. However, what starts out as something that seems like a solution often becomes part of the problem and can even make chronic pain worse.
- Mindfulness- and acceptance-based interventions are effective for pain (McCracken and Vowles, 2014) and AUD (Bowen et al., 2014), and may be effective for the treatment of comorbid pain and AUD, particularly given recent evidence of effectiveness in the treatment of comorbid pain and OUD (Garland et al., 2014).
- Additionally, the commensal microbiota may have restored nociceptor sensitization by stimulating toll-like receptors 36.
- This also may interfere with efficiency in descending pain inhibition at the midbrain level and precipitate development of chronic pain conditions in which deficiency in descending pain modulatory system is thought to be a central cause (Ossipov et al., 2014).
- Likewise, pain interfered with daily activities ‘moderately’ to ‘extremely’ among 34% of men and 29% of women with drinking problems, compared to 16% and 19% of the men and women without drinking problems.
- The seminal gate control theory of pain shifted pain research from the Cartesian view of the brain as a passive receiver of pain signals presumed to be generated in damaged tissue to the current understanding of the central nervous system as the dynamic source of pain 65.
The goal of this review is to provide a broad translational framework that communicates research findings spanning preclinical and clinical studies, including a review of genetic, molecular, behavioral, and social mechanisms that facilitate interactions between persistent pain and alcohol use. We also consider recent evidence that will shape future investigations into novel treatment mechanisms for pain in individuals suffering from AUD. The neurotransmitters involved in excitatory interactions include glutamate and substance P, while inhibitory neurotransmitters include GABA.
How alcohol consumption contributes to chronic pain
People debating the dress color were incredulous—how can others looking at the identical image see colors that were undoubtedly wrong as informed by their own eyes? One possible explanation came from an empirical study showing that the ambiguous nature of the image required spontaneous assumptions about the source of lighting in the image for disambiguation, assumptions that differed depending on an individuals’ prior life experiences 157. Similarly nociceptive-related signals, possibly emerging at multiple levels of the pain system, and homeostatic/allostatic feedback may sometimes be ambiguous to the pain system. The uncertainty of pain and other harmless bodily sensations (see 158) may be disambiguated by the individual’s prior life experiences, expectations, and beliefs resulting in divergent interpretations and idiosyncratic experiences of pain.
A considerable drawback of the liquid diet and vapor models is their forced (i.e., non-contingent) method of alcohol administration, although both models can be combined with operant self-administration to measure volitional alcohol intake, the motivation for alcohol, and compulsive-like alcohol consumption despite punishment. Both models also allow for the maintenance of high BALs over extended periods of time to reliably model dependence symptoms. One of the important risk factors for relapse to drinking and for the development of AUD and other substance use disorders, is impulsivity. Impulsivity is multidimensional construct referring to a predisposition for individuals to react quickly in response to an internal or external stimulus, without consideration of the possible negative consequences (Lejuez et al., 2010). While not a prominent trait in chronic pain patients, impulsivity may be especially relevant to individuals with AUD who suffer from chronic pain. These individuals would be in a situation that is analogous to what has been described for opioid analgesic misuse risk in chronic, low-back pain patients who had been prescribed opioid analgesics (Marino et al., 2013).
As seen in other sensory modalities, top-down processing is fundamental to the construction of percepts resulting in individual differences in perceptions of the external world as revealed by ambiguous stimuli. As an example, consider the image of “the dress” that took the internet by storm in 2015 generating substantial interest among the public and the vision science community. Some observers perceived an overexposed image of a dress as black and blue—the actual color of the dress—while to others the dress appeared gold and white.
Nociceptors expressed by first-order sensory neurons of the spinal cord (dorsal root ganglion, DRG), for example, transduce signals—mechanical, thermal, or chemical—from the environment into neural information that is conducted to second-order neurons within the dorsal horn of the spinal cord for nociceptive processing. The relay of nociceptive information to the brain is necessary for the subjective (conscious) sensation of pain (i.e., nociceptive-pain), however nociception itself (i.e., nociceptor activity) is not sufficient for the sensation of pain nor necessary for the perception of pain. Indeed, Sherrington introduced the concept of nociception to account for the skin’s “special sense of its own injury” and the discovery, in an experimental spinal dog preparation, that a reflexive defensive withdrawal response continues to be elicited despite the separation of the spinal cord from the brain 10.