A new study published in the British Journal of Pharmacology showed that chronic alcohol consumption can increase pain sensitivity through two distinct biochemical processes, one driven by alcohol intake and the other by alcohol withdrawal.

Pain is one of the many side effects of long-term alcohol consumption, with more than half of people with alcohol use disorder (AUD) suffering from persistent pain of some kind, including alcoholic neuropathy. AUD has also been linked to changes in how the brain perceives pain signals as well as alterations in how the immune system activates. Furthermore, people with AUD can also experience allodynia during withdrawal, which is the perception of an innocuous stimulus as painful.

In the study, the researchers from Scripps Research compared three groups of test subjects, i.e., subjects that were dependent on alcohol (excessive drinkers), subjects who had limited access to alcohol and were not considered dependent (moderate drinkers), and those who had never been given alcohol.

In dependent subjects, allodynia developed during alcohol withdrawal, and subsequent alcohol access significantly decreased pain sensitivity. Separately, about half of the subjects who were not dependent on alcohol also showed signs of increased pain sensitivity during alcohol withdrawal, but, unlike the dependent test subjects, the neuropathy was not reversed by re-exposure to alcohol.

The researchers also evaluated the levels of inflammatory proteins and observed that, while inflammation pathways were higher in both dependent and non-dependent subjects, particular molecules were exclusively elevated in dependent test subjects. This suggested that inflammatory proteins can be used as therapeutic targets to treat alcohol-related pain. 

(Source: https://theprint.in/health/study-shows-how-alcohol-consumption-contributes-to-chronic-pain/1533169/ )