What do we (not) know about how paracetamol (acetaminophen) works?

What is known and background:  Although paracetamol (acetaminophen), N‐(4‐Hydroxyphenyl)acetamide, is one of the world’s most widely used analgesics, the mechanism by which it produces its analgesic effect is largely unknown. This lack is relevant because: (i) optimal pain treatment matches the analgesic mechanism to the (patho)physiology of the pain and (ii) modern drug discovery relies on an appropriate screening assay.

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