Gastro-Retentive Drug Delivery System

1. A
SEMINAR ON
Topic: Gastro- Retentive Drug Delivery System
Presented By:
Hariom Jaiswal
M. Pharm (Pharmaceutics)
1st Year / 1st Sem
(2021-22)
INSTTITUTE OF TECHNOLOGY OF MANAGEMENT
GIDA, GORAKHAPUR, U.P

2. CONTENTS:
1. INTERODUCTION
2. POTENIAL CANDIDATES FOR GRDDs
3. APPROACHES GRDDs
4. ADVANTAGES
5. DISADVANTAGES
6. APPLICATION
7. REFERENCES

3. INTRODUCTION OF GRDDs:
• Gastro- retentive drug delivery is an approach to
prolong gastric residence time, there by targeting site
specific drugs release in upper gastrointestinal tract
(GIT) for local or by retaining dosage form into
stomach and by releasing the in controller manner .
• Oral drug administration has been the predominant
route drug delivery.
• Gastric residence is time which a drug resides in
stomach
• Depend upon fluid and food intake.
• GRDDs are designed to delay gastric emptying.

4. POTENTIAL CANDIDATES FOR GRDDs:
• Drugs acting locally in the stomach.
• Drugs that are primarily absorbed.
• Drugs that is poorly soluble at alkaline pH.
• Drugs with a narrow absorption window.
• Drugs which are absorbed rapidly form the GI tract.
• Drugs that degrade in the colon.
• Drugs with less half life.
• Drugs that disturb normal colonic microbes.

5. APPROACHES TO GRDDs:
A.Low density/ Floating system.
B.Bio-adhesive system or Muco-adhesive.
C.High density system.
D.Swellable system.

6. A. LOW DENSITY / FLOATING SYSTEM:
Floating drug delivery system have a bulk density lower then
gastric fluids and thus remain
buoyant in the stomach for prolong period time, without affecting
the gastric emptying rate.
While the system in floating on the gastric contents, the drug is
released slowly at a deisred
rate form the system . This type is also called as hydro-
dynamically balanced system (HBS).

7. MACHANISM OF FDDs:
FDDs has a bulk density lees then gastric fluid and remain
buoyant in the stomach without
affecting the gastric emptying rate for a prolonged period time .
F = Buoyancy- Gravity
= (Df-Ds)gv
Where-
F = Total vertical force.
Df = Fluid density.
Ds = Object Density.
V = Volume

8. TYPE OF FLOATING SYSTEM:
1.Effervescent system.
2.Non – effervescent system.
1.Effervescent system: A drug delivery system can be made
to float in the stomach by incorporating chamber which may
be filled with vacuum , air or inert gas. The gas in floating
chamber can be introduced either by volatilization of an organic
solvent or by effervescent reaction between organic acids and
bicarbonate salt. These effervescent system further classified into
two types : a. Volatile liquid or Vacuum containing system .
b. Gas generating system.

9. 2. Non – effervescent system: It is the FDDS is based on
mechanism of swelling of polymer or bio-adhesionto mucosal
layer in GI tract . The most commonly used excipient in non-
effervescent FDDS are gel forming or highly swellable type
hydrocolloids hydrophilic gums and matrix forming such as
polycarbonate polyacrylate etc as well as a bio-dhesive polymer
such as Carbopol this system can be further divided in to the sub-
types: a. Hydrodynamically balanced systems.
b. Micro-balloons / Hollow microspheres.
B. BIOADHESIVE SYSTEM: Bio/mucoadhesive system are
those which bind to the gastric epithelial call surface or mucin and
serve as a potential means of extending the Gastro retention of
drug delivery system (DDS) in the stomach by increasing the
intimacy and duration of contact of drug with the biological
membrane.

10. A bio/mucoadhesive substances is a natural or synthetic
polymer capable of producing an adhesive interaction based on
hydration mediated , bonding mediated or receptor mediated
adhesion with a biological membra lining of GI mucosa.
ADVANTAGES OF GRDDs:
• Local action.
• Improved drug absorption.
• Enhanced bio-availabilty.
• Controlled drug delivery of drug.
• Site specific drug delivery.

11. DISADVANTAGES OF GRDDs:
• Drug that cause gastric lesion.
• Drug that undergo first pass metabolism.
• Drug that have very limited acid solubility and stability.
• Drug that degrade in acidic environment.
• Requires high levels of fluid in stomach.
• Requries presence of blood to delay gastric emptying.
APPLICATION:
• Enhanced bioavilability.
• Sustained drug
• delivery system

12. REFERENCES:
• https://www.slideshare.net/ShwetaNehate/gastro-retentive-
drug-delivery-system-ppt-grdds
• https://www.slideshare.net/AnkitMalik60/ankit-gastro-
retentive-drug-delivery-system
• https://www.slideshare.net/sumelashique/gastro-retentive-
drug-delivery-system-by-sumel-ashique