The hidden risks of alcohol use for pain relief (2025)

Published in final edited form as: Alcohol Clin Exp Res (Hoboken). 2023 Jan 3;47(2):209–210. doi: 10.1111/acer.15005

Chronic pain affects over 100 million individuals in the United States alone, more than cancer, diabetes, and heart disease combined (Dahlhamer et al., 2018). Pain is an inescapable and often invisible morbidity, being one of the leading causes of disability worldwide. Humans have used alcohol for pain management for millennia, although the precise mechanisms underlying alcohol analgesia are largely unknown, especially when compared to more notoriously abused substances such as opioids (Witkiewitz and Vowles, 2018; Pahng and Edwards, 2021). A valuable meta-analysis constructed a dose-effect curve for alcohol analgesia in human subjects (Thompson et al., 2017) while issuing the warning that alcohol use near or above binge drinking levels is typically required for effective pain relief. An important recent study (Vitus et al. 2022) examined alcohol analgesia in chronic jaw pain sufferers at this exposure level (around 0.08 g/dL), which also corresponds to the legal driving limit in several jurisdictions. The major research question explored was whether the efficacy of alcohol to relieve pain might be altered in individuals with a history of chronic pain. Given the highly subjective nature of pain and its hypothesized intersection with higher brain reward and nociceptive processes that may underlie important cognitive-affective transdiagnostic factors (Zale et al., 2021), the authors also emphasized the need to assess a battery of pain-related dimensions (pain relief, pain intensity, and pain unpleasantness).

Consistent with previous work, Vitus and colleagues found significant effects of alcohol to reduce pain symptoms, although this did not appear to be modulated by chronic pain status. This conclusion challenges some existing preclinical and clinical findings suggesting that pain history and pain severity increases motivation for alcohol (e.g., Brennan et al., 2005). However, the authors posit that individuals with chronic pain may be presented with more frequent opportunities to consume alcohol for pain relief compared to non-pain populations. Some important limitations of the Vitus study include the recruitment of a limited sociodemographic sample, focus on a single pain modality (mechanical nociception), and use of a single alcohol dose (target of 0.08 g/dL). It would be interesting to understand whether a more diverse set of chronic pain patients are more sensitive to similar or even lower doses of alcohol (modeling recreational drinking). While socially marginalized groups are often excluded from clinical trials and human studies, an intersection of biopsychosocial variables and more precise modeling may reveal novel associations between pain constructs and substance use variables (Craig et al., 2020).

Although the current study found no significant differences in recent drinking between pain and non-pain groups, another recent study from the Boissoneault group suggests that alcohol demand is highest in drinkers who consume alcohol for both therapeutic and recreational purposes (Ferguson et al., 2022), and this motivational dimension may play a crucial role in reinforcement processes related to increased quantity or frequency of alcohol use in the context of pain. In this regard, a focus on interactions between chronic pain and binge drinking patterns in individuals displaying a higher Alcohol Use Disorder Identification Test (AUDIT) score would be valuable. Over time, binge drinking places individuals at risk for the development of alcohol use disorder (AUD) and can also result in the damage of multiple organ systems (Simon et al., 2021). Moreover, evidence suggests that the pain-relieving effects of alcohol may diminish over time (Neddenriep et al., 2019), further motivating individuals to escalate drinking. Keeping pace with the recent intensive research focus on prescription opioids, more translational work is needed to elucidate physiological mechanisms of alcohol analgesia (Cucinello-Ragland and Edwards, 2020), analgesic tolerance (Elvig et al., 2021), and how recent versus lifetime alcohol drinking patterns and intensities may shift the balance between alcohol-related analgesia and hyperalgesia. Such a shift would be predicted to drastically alter the motivational mechanisms for alcohol use (Ditre et al., 2019).

Interestingly, the effects of alcohol on pain symptoms were greatest in terms of subjective pain relief as compared to pain intensity, unpleasantness, or threshold, suggesting that the latter, commonly used metrics may not effectively assess the negative reinforcing effects of alcohol. Alcohol use for either somatic or affective pain relief resonates strongly with negative reinforcement theories of AUD (Koob et al., 2014), particularly as heavy lifetime alcohol use can produce neuropathic pain symptoms that may trap individuals into a cycle of drinking to self-medicate ever-present hyperalgesia symptoms (Edwards et al., 2020). Recently, several important clinical studies have shed light on important relationships between the many psychological dimensions of pain and motivation for substance use. One conceptualization has been termed the CANUE (Catastrophizing, Anxiety, Negative Urgency, and Expectancy) model (Ferguson et al., 2021). This model aims to better understand the specific dimensions of pain that precede and predict problematic substance use, so that targeting these features may provide better pain-coping strategies before substance use disorders emerge or worsen. Employment of such conceptualizations in the opioid field has revealed that pain-related distress predicts future opioid cue-induced craving (Ren et al., 2009). Similarly, reductions in pain symptoms in patients from alcohol-treatment centers associate with a lowered risk of future relapse (Jakubczyk et al., 2016).

Recent scientific, political, and legal developments are rapidly shifting how health professionals recommend and prescribe analgesic medications and other interventions to combat what will be a continuing (if not growing) global epidemic of chronic pain (Global Burden of Diseases and Injuries Collaborators, 2020). Our understanding of how at-risk alcohol use and AUD management fit into this future strategy represents urgent research and educational priorities and will require the strengthening of interdisciplinary ties within the preclinical and translational neurosciences.