1. What Is Percentage Drug Release?

Percentage drug release is a critical parameter in pharmaceutical dissolution testing that measures the amount of active pharmaceutical ingredient (API) released from a dosage form over time. It is expressed as a percentage of the total drug content in the formulation.

2. How Does The Calculator Work?

The calculator uses the percentage drug release formula:

Where:

• \( Amount\ Released \) — Amount of drug dissolved in the dissolution medium (mg)
• \( Total\ Amount \) — Total drug content in the dosage form (mg)

Explanation: This calculation determines what percentage of the total drug has been released from the formulation during dissolution testing.

3. Importance Of Dissolution Testing

Details: Dissolution testing is essential for evaluating drug product performance, ensuring batch-to-batch consistency, predicting in vivo performance, and meeting regulatory requirements for drug approval and quality control.

4. Using The Calculator

Tips: Enter the amount released (measured from dissolution testing) and total amount (theoretical drug content) in milligrams. Both values must be positive, and the amount released cannot exceed the total amount.

5. Frequently Asked Questions (FAQ)

Q1: Why is percentage drug release important?
A: It indicates how much drug is available for absorption, helps predict bioavailability, and ensures product quality and consistency.

Q2: What are typical acceptance criteria for dissolution?
A: Varies by product, but common criteria include Q=80% in 30 minutes for immediate release, or specific time points for extended release formulations.

Q3: How is amount released measured?
A: Typically measured using UV spectrophotometry or HPLC analysis of dissolution medium samples at specified time intervals.

Q4: What factors affect drug release?
A: Formulation factors (excipients, manufacturing process), physicochemical properties of the drug, and dissolution conditions (pH, agitation, temperature).

Q5: When should dissolution testing be performed?
A: During product development, batch release testing, stability studies, and whenever formulation or manufacturing changes occur.