Biopharmaceutics

Question 1

What is biopharmaceutics?

Answer 1

It is the study of the relationship between the physiochemical properties of a drug, the dosage form, and route of administration on the rate and extent of systemic drug absorption

Question 2

What equation dictates the rate of dissolution or oral dosage forms?

Answer 2

Fick’s Law (refer to page 6 in Intro to Biopharmaceutics)

Question 3

What is the definition of absorption?

Answer 3

The process by which unchanged drug is released from the dosage form (disintegration/dissolution) and proceeds from administration site into systemic circulation

Dissolution (drug dissoves into aqueous environment) and Permeation (drug crosses membrane barriers into systemic circulation) are components of absorption

Question 4

What are the rate-limiting steps in oral absorption?

Answer 4

Dissolution and Permeation

Question 5

How can dissolution processes be enhanced with oral dosage forms?

Answer 5

Take drug with water

Question 6

What are some pharmacokinetic variables that apply to absorption?

Answer 6

Ka (absorption constant): rate of absorption

F (bioavailability): extent of absorption

Cmax, Tmax, and AUC are all descriptive PK parameters that describe the extent of absorption