The therapeutic index (TI) of a drug is best defined as:
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Correct answer: The ratio of LD50 to ED50
The therapeutic index is classically defined as the ratio of the median lethal dose (LD50) to the median effective dose (ED50). It provides a quantitative estimate of a drug’s relative safety in animal studies. A larger TI indicates a wider margin between effective and lethal doses.
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More Therapeutic Index questions
- A drug with a high therapeutic index is generally considered to be:
- Which of the following drugs is known to have a narrow therapeutic index?
- If the ED50 of a drug is 10 mg and the LD50 is 100 mg, the therapeutic index is:
- The therapeutic window of a drug refers to:
- Which factor does NOT directly influence the therapeutic index of a drug?
- A narrow therapeutic index implies that: