Medical Research Council - London Institute of Medical Sciences

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Opioid Alternatives

Drugs that reduce pain molecule BH4 are promising alternatives to highly addictive opioids for treating pain

12 October 2022

Opioid Alternatives

Pain, whether intense or mild, brief or chronic, is detected by specialised sensory neurons that relay signals to the brain. When pain is bad or persistent enough to warrant painkillers, opioids are among the most effective at blocking this signal relay. But these drugs are highly addictive and, at high doses, can lower heart rate and breathing to a fatal degree. In looking for safer, non-addictive painkillers, scientists have screened thousands of existing drugs with various uses to find ones that act on sensory neurons (green) to reduce production of a known pain molecule, BH4 (magenta). Cells expressing BH4 appear magenta and/or white. In addition to some drugs with known analgesic effects, researchers found a schizophrenia drug that, at low doses, suppressed BH4 production. If this, or other BH4-lowering substances, can be further developed, it may be possible to have painkillers as powerful as opioids but without the devastating downsides.

Written by Ruth Williams

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