Scientific Evidence-Based Mechanism of Acupuncture on Analgesia

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Nunnapas Jiwlawat
Sumit Durongphongtorn


Traditional Chinese acupuncture has been routinely used worldwide as an adjunctive therapy for alleviating chronic pain because the long-term usage of analgesic drugs, prescribed in western medicine, may cause adverse side-effects or may provide unsatisfactory pain relief. However, the underlying analgesic mechanism of how acupuncture modulates the nervous system and pain pathways resulting in pain alleviation has not been revealed. In the last decade, more than 1,000 scientific researches have been published and proven that acupuncture interferes with pain signals at the various levels of nociception: peripheral, spinal cord, and brain. Acupuncture analgesic effects have significantly relied on the type of pain, type and location of acupuncture, frequency of electrical stimulation, and experience of the acupuncturist. Recent scientific evidence shows that the major analgesic effects of acupuncture are a result of the triggered release of endogenous-opioid in patients. Acupuncture induces serotonin and norepinephrine release which inhibit descending nociceptive transmission. Acupuncture also increases the pain threshold and reduces inflammatory reactions via a decreasing inflammatory mediator released from the peripheral nociceptive areas. In this review, we gather critical scientific proof from highlighted scientific research and summarize them into the analgesic mechanism of acupuncture. Lastly, we discuss challenges and future directions of scientific research on acupuncture.


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