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Medicine

Opioid-Induced Hyperalgesia vs. Tolerance in Chronic Pain Patients

Quick fact

Opioid-induced hyperalgesia (OIH) is a paradoxical reaction where opioids increase pain sensitivity, sometimes even triggering pain in areas that weren't previously painful. It can occur even with normal doses, not just after prolonged high-dose use.

Why this is interesting

You're taking a powerful painkiller, yet your pain seems to get worse. How can a drug meant to relieve pain actually make it more intense?