1. What Is Therapeutic Index?

The Therapeutic Index (TI) is a quantitative measurement of the safety of a drug. It represents the ratio between the toxic dose and the therapeutic dose of a pharmaceutical compound.

2. How Does The Calculator Work?

The calculator uses the Therapeutic Index formula:

Where:

• \( LD_{50} \) — Lethal dose for 50% of the population (mg/kg)
• \( ED_{50} \) — Effective dose for 50% of the population (mg/kg)

Explanation: A higher therapeutic index indicates a wider margin of safety between the effective dose and the toxic dose of a drug.

3. Importance Of Therapeutic Index

Details: The therapeutic index is crucial in pharmacology for assessing drug safety, determining appropriate dosing regimens, and comparing the safety profiles of different medications.

4. Using The Calculator

Tips: Enter both LD50 and ED50 values in mg/kg. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What does a high therapeutic index indicate?
A: A high therapeutic index indicates that a drug has a wide safety margin, meaning there's a large difference between the effective dose and the toxic dose.

Q2: What is considered a good therapeutic index?
A: Generally, a therapeutic index of 10 or higher is considered good, indicating the drug is relatively safe. Values below 3 may indicate a narrow therapeutic window.

Q3: How is therapeutic index used in clinical practice?
A: It helps clinicians determine appropriate dosing, monitor for potential toxicity, and compare the safety of different treatment options.

Q4: Are there limitations to therapeutic index?
A: Yes, it doesn't account for individual variations in drug metabolism, drug interactions, or specific patient factors that may affect drug safety.

Q5: Can therapeutic index be applied to all drugs?
A: While applicable to most drugs, some medications with complex mechanisms or those used in critical care may require additional safety assessments beyond the therapeutic index.