therapeutic index
noun
: a measure of the relative desirability of a drug for the attaining of a particular medical end that is usually expressed as the ratio of the largest dose producing no toxic symptoms to the smallest dose routinely producing cures
Examples of therapeutic index in a Sentence
Recent Examples on the Web
It is known as a narrow therapeutic index (NTI) drug.
—
Karen Berger, Pharmd, Verywell Health, 20 Feb. 2025
The risk of lithium toxicity, given the narrow therapeutic index, is why patients on lithium are closely monitored.
—Lydia Wang, refinery29.com, 24 June 2021
The therapeutic index gives you the window in which the drug will be effective against the virus without causing undue side effects.
—William A. Haseltine, Scientific American, 1 Oct. 2020
Many antibiotics have a sufficiently high therapeutic index to allow for a single dose to be used.
—Richard Klasco, New York Times, 8 June 2018
Because these trials are a mandatory step in the Food and Drug Administration approval process, each drug’s therapeutic index is well defined.
—Richard Klasco, New York Times, 8 June 2018
The therapeutic index is the ratio of a drug’s efficacy to its toxicity.
—Richard Klasco, New York Times, 8 June 2018
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Karen Berger, Pharmd, Verywell Health, 20 Feb. 2025
The risk of lithium toxicity, given the narrow therapeutic index, is why patients on lithium are closely monitored.
—Lydia Wang, refinery29.com, 24 June 2021
The therapeutic index gives you the window in which the drug will be effective against the virus without causing undue side effects.
—William A. Haseltine, Scientific American, 1 Oct. 2020
Many antibiotics have a sufficiently high therapeutic index to allow for a single dose to be used.
—Richard Klasco, New York Times, 8 June 2018
Because these trials are a mandatory step in the Food and Drug Administration approval process, each drug’s therapeutic index is well defined.
—Richard Klasco, New York Times, 8 June 2018
The therapeutic index is the ratio of a drug’s efficacy to its toxicity.
—Richard Klasco, New York Times, 8 June 2018
Cite this Entry
“Therapeutic index.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/therapeutic%20index. Accessed 18 Jul. 2025.
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