# What does EC50 measure?

## What does EC50 measure?

In pharmacology, the potency of a compound is expressed as the half-maximal effective concentration (EC50), which refers to the concentration of a drug that induces a response halfway between the baseline and maximum.

## What is the difference between EC50 and IC50?

The EC50 is the concentration of a drug that gives half-maximal response. The IC50 is the concentration of an inhibitor where the response (or binding) is reduced by half.

**Is EC50 and ED50 the same?**

* EC50 versus ED50: EC50 is the dose required for an individual to experience 50% of the maximum effect. ED50 is the dose for 50% of the population to obtain the therapeutic effect.

**How do I know if I have EC50?**

The EC50 is defined quite simply as the concentration of agonist that provokes a response halfway between the baseline (Bottom) and maximum response (Top). It is impossible to define the EC50 until you first define the baseline and maximum response.

### How do you calculate EC50 in Excel?

Select the data, insert a “scatter plot,” and set the Y-axis to “logarithmic.” It should be approximately linear over some range. Select “add trend line” and pick “exponential.” Then display equation and you’ve got it. I attached an example. ED50V10 (Readme) is an Excel add-in for calculating IC50/EC50 values.

### What is ED50 of a drug?

The ED50 (median effective dose) is the dose of a medication that produces a specific effect in 50% of the population that takes that dose.

**Why do we use EC50?**

More simply, EC50 can be defined as the concentration required to obtain a 50% […] effect and may be also written as [A]50. It is commonly used as a measure of a drug’s potency, although the use of EC50 is preferred over that of ‘potency’, which has been criticised for its vagueness.

**What is log concentration?**

Using a logarithmic x-axis (concentration) spreads out the data so the shape of the curve and the quality of the fit are readily visible when the concentrations cover a wide range, as it is not uncommon to cover a range of at least 500-fold in concentration in an IC50 measurement.

## How do you calculate log concentration in Excel?

Excel LOG Function

- Summary. The Excel LOG function returns the logarithm of a given number, using a supplied base. The base argument defaults to 10 if not supplied.
- Get the logarithm of a number.
- The logarithm.
- =LOG (number, [base])
- number – Number for which you want the logarithm. base – [optional] Base of the logarithm.

## What is ED50 in pharmacology?

**What is EC50 and ED50 in pharmacology?**

The EC50 (or ED50) is the concentration (or dose) effective in producing 50% of the maximal response and is a convenient way of comparing drug potencies. From: Medical Pharmacology and Therapeutics (Fifth Edition), 2018.

**What is ED50 and LD50?**

Therapeutic index is defined as follows: LD50, or median lethal dose, is the dose of drug that causes death in 50% of experimental animals, and ED50, or median effective dose, is the dose that produces a specified effect (“response”) in 50% of the population under study.

### Why do we use log concentrations?

### What is the meaning of log E?

The natural log function of e is denoted as “loge e”. It is also known as the log function of e to the base e. The natural log of e is also represented as ln(e)

**What is the difference between the EC50 and logec50 scales?**

If you have an odd number of values, the median of the EC50 will be equivalent to the mean of the logEC50. If you have an even number of values, then the median involves taking the mean of the middle two values, so the result will be a bit inconsistent in the EC50 and logEC50 scales, but the difference is not likely to be huge.

**Should I average the EC50 or logec50 values in prism?**

The midpoint that Prism computes is the logEC50, which will have a distribution closer to a Gaussian distribution than will the EC50. Therefore, you should average the logEC50 values, not the EC50 values.

## What is the geometric mean of the EC50 values?

The mean of the logEC50 values is -7.544, and the standard error of the mean is of 0.03776. The antilog of the mean (10 -7.544) is 2.86E-08 or 28.6 nM. This is the geometric mean of the EC50 values. The antilog of the standard error (10 0.03776) equals 1.09.

## What is the mean and standard error of logec50?

The mean of the logEC50 values is -7.544, and the standard error of the mean is of 0.03776. The antilog of the mean (10 -7.544) is 2.86E-08 or 28.6 nM.