Therapeutic Index
Therapeutic Index — The ratio between the toxic dose and the effective dose of a compound, used as a measure of relative safety in pharmacological research.
What Is Therapeutic Index?
Therapeutic index (TI) is the ratio of the toxic dose to the effective dose (TI = TD50/ED50 or LD50/ED50), quantifying a drug's safety margin. A higher TI indicates a wider margin between efficacy and toxicity. Peptides generally exhibit high therapeutic indices due to their target specificity, though off-target receptor activation can narrow the safety window.
Peptide Context
- High TI peptides: Ipamorelin (selective GHS-R1a agonist without cortisol/prolactin effects) demonstrates how selectivity improves TI
- Lower TI: GHRP-6 (stimulates GH, cortisol, prolactin, and appetite) has a narrower effective window
- AMP selectivity: The therapeutic index for AMPs is defined as hemolytic concentration / MIC, measuring selectivity for bacterial vs. mammalian membranes
Frequently Asked Questions
What is Therapeutic Index?
The ratio between the toxic dose and the effective dose of a compound, used as a measure of relative safety in pharmacological research.
Why is Therapeutic Index important in peptide research?
Therapeutic Index is a fundamental concept in pharmacology as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.
Authority Sources
- Therapeutic Index on Wikipedia
- Search Therapeutic Index on PubChem (NIH)
- Research articles on ScienceDirect