1. Health

Medication Tolerance


Updated August 28, 2008

Definition: Tolerance occurs when your body gets used to a medication so that either more medication is needed to give you the desired effect or a different medication is needed. Depending on the drug, tolerance can develop in several days or happen more gradually over a number of weeks.

Tolerance can have positive result such as a reduction in unpleasant side effects due to the medication. However, as your body becomes tolerant to the medication, it becomes less effective.

Also Known As: drug tolerance
Medication tolerance is most often related to drugs that affect your body’s brain and nervous system including:
  • painkillers such as Oxycontin (oxycodone)
  • tranquilizers such as Valium (Diazepam)
  • over-the-counter sleep aids such as Benadryl (diphenhydramine)

To learn more about your specific medication, use Drugs A to Z.

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