Opioid overdose

Tolerance

Tolerance is a physiological state characterised by a decrease in the effects of a drug (e.g., analgesia, nausea, or sedation) with chronic administration.

Physical dependence

Physical dependence is the physiological adaptation of the body to the presence of an opioid. It is defined by the development of withdrawal symptoms when opioids are discontinued, when the dose is abruptly reduced, or when an antagonist such as naloxone is administered.

Opioid-naive patients

Opioid-naive patients are those who have never taken opioids.