tolerance
Quick Summary
In physiology, tolerance refers to the body's diminished response to a substance, like a drug, due to repeated exposure or use. This adaptation means an individual may need increasing amounts of a substance to achieve the same effect. For instance, with opiates, tolerance can develop to a degree where a user might need 5,000 mg daily, a dose nearly 200 times what would be dangerous for a normal adult. Tolerance is a key characteristic of addiction, though it can be independent of physical dependence. This phenomenon is also observed in how organisms adapt to environmental factors, such as temperature, where their capacity to endure unfavorable conditions is crucial for survival.123
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drug usePhysiological effects of addictionTolerance is a physiological phenomenon that requires the individual to use more and more of the drug in repeated efforts to achieve the same effect. At a cellular level this is characterized by a diminishing response to a foreign substance (drug) as a result of…
Read MoreTolerance is a physiological phenomenon that requires the individual to use more and more of the drug in repeated efforts to achieve the same effect. At a cellular level this is characterized by a diminishing response to a foreign substance (drug) as a result of…
Read More- drug useAmphetamines
…produce habituation, drug dependency, physiological tolerance, and toxic effects, but no physical addiction.
Read More…produce habituation, drug dependency, physiological tolerance, and toxic effects, but no physical addiction.
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analgesicOpioid analgesics…loss in effectiveness is called tolerance. Evidence suggests that tolerance is not due to alterations in the brain’s responses to drugs. Animals exhibiting tolerance to morphine after repeated injections in a familiar environment show little or no tolerance when given the same doses and tested for pain sensitivity in new…
Read More…loss in effectiveness is called tolerance. Evidence suggests that tolerance is not due to alterations in the brain’s responses to drugs. Animals exhibiting tolerance to morphine after repeated injections in a familiar environment show little or no tolerance when given the same doses and tested for pain sensitivity in new…
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drug abuseAnother related phenomenon is tolerance, a gradual decrease in the effect of a certain dose as the drug is repeatedly taken; increasingly larger doses are needed to produce the desired effect. Tolerance does not always develop. It is most marked with habitual opiate users. The term addiction is often…
Read MoreAnother related phenomenon is tolerance, a gradual decrease in the effect of a certain dose as the drug is repeatedly taken; increasingly larger doses are needed to produce the desired effect. Tolerance does not always develop. It is most marked with habitual opiate users. The term addiction is often…
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