Drug Absorption Biopharmaceutics

1. Name : Atanu Mandal
Roll No : 20801920084
Subject Code : PT616
Semester : 5th
Year : 3rd Year
Drug
Absorption

2. CONTENTS
• Introduction
• Mechanism of Drug Absorption
• Factors Influencing Absorption
• References

3. Introduction
❑ Biopharmaceutics:
The study of the chemical and physical properties of drugs and the biological
effects they produce.
❑ Pharmacokinetics:
Pharmacokinetics is the science of the kinetics of drug absorption distribution
and elimination.
❑Drug Absorption
The process of movement of unchanged drugs from the site of administration
system to systemic circulation.
Bioavailiability of drug depend upon drug absorption to the circulation.

4. Mechanism of Drug Absorption
1. Transcellular / Intracellular
Transport:
A. Passive Transport
Processes
I. Passive diffusion
II. Pore Transport
III. Ion-pair transport
IV. Facilitated diffusion
B. Active transport processes
I. Primary
II. Secondary
a. Symport(Co-
transport)
b. Antiport(Counter
transport)
2. Paracellular / Intercellular
Transport
A. Permission throw tight
junction of epithelial cells
B. Persorption
3. Vesicular or Corpuscular
Transport(Endocytosis)
A. Pinocytosis
B. Phagocytosis
There three categories are-

5. Passive Transport
➢ No energy is required.
➢ It is a downhill Transport.
➢ Greater the surface surface area more the
absorption of drug.
➢Passive transport classified the following types –
1. Passive Diffusion
2. Pore transport
3. Ion pair transport
4. Facilitated Diffusion

6. Passive Diffusion
➢ Non ionic Diffusion.
➢ Major process of absorption(more than 90%)
➢ Electrochemical gradient manifestation.
➢ Partition Co-Efficient.
➢ Follow Fick’s law.

7. Ion Pair Transport Pore Transport

8. Facilitated Diffusion

9. Active Transport
➢ Energy is required.
➢ ATP required.
➢Active transport classified the following types –
1. Primary Active Transport
2. Secondary Active Transport

10. Factors Affecting Drugs Absorption
➢ Drug solubility
➢ Particle size and surface area
➢ Polymorphism and add and
Amorpism
➢ Speudomorphism
➢ Salts of drugs
➢ Lipophilicity
➢ Drug stability
➢ Stereochemistry
Pharmaceutical Factor Patient Factor
➢ Age
➢ Gastric Emptying time
➢ Intestinal transt time
➢ Disease state
➢ Blood flow through GIT
➢ GIT contents
• Food
• Fluids
• Other Drugs

11. References
❖ DM Brahmankar, Sunil B. Jaiswal, Biopharmaceutics and Pharmacokinetics
Published byMK Jain for VALLABH PRAKASHANⓇ 3rd edition, ISBN 978-81-
85731-93-3 VPBN 32

12. Thank You