Tolerance and addiction
Tolerance is the physiologic adaptation to a given drug such that the individual may develop faster metabolism and less of a physiologic response to the original dose.
Addiction is the psychological dependence on a drug for nontherapeutic effects such as euphoria, sedation, or psychedelic experiences.
In both instances, abrupt withdrawal of the drug may lead to withdrawal syndrome as is often seen with abrupt cessation of opioids, benzodiazepines, barbiturates, etc.
