Bilayer floating tablet technology provides a means to separate incompatible drugs and control drug release profiles. It utilizes lower density to allow tablets to float in the stomach for prolonged periods, increasing bioavailability and allowing for sustained delivery of drugs that are absorbed in the stomach. Evaluation tests examine properties like floating lag time and dissolution rates in vitro and gastric retention in vivo. Several commercial bilayer floating tablet products are available.

1. Bilayer Floating Tablet Technology: An Overview
By
Dipanjoy Ghosh(11700828)
Under the guidance of
Mr. Narendra Kumar Pandey
(Associate Professor, Pharmaceutical Sciences)
School of Pharmaceutical Sciences,LPU

2. Introduction
Basic GIT physiology
Process of gastric emptying
Mechanism of FDDS
Approaches for prolonging the gastric residence time
Classification
Importance of FDDS
Factor affecting floating time
Advantage of FDDS
Disadvantage of FDDS
Evaluation tests
Examples
Conclusion
Reference
2

3. Bilayer tablets can be a primary option to avoid chemical
incompatibilities between API by physical separation, and to enable
the development of different drug release profiles (immediate
release with control release).
Floating drug delivery system or hydro dynamically balance systems
have a bulk density lower than gastric fluid and thus remains buoyant in
the stomach for a prolonged period of time.
3
Patel Mehul, Challenges in the formulation of bilayered tablets: a review.
IJPRD; Vol. 2; 2010, 30-42.

4. BASIC GIT PHYSIOLOGY
• Reservoir for ingested
material.
fundus
• Reservoir for ingested
material.
body
•Major site of mixing motion.
•Acting as pump to propel gastric
contents for gastric emptying.pylorus
4
Asha S, Senthil K, Parthiban S. “Bilayer Floating Tablet – A Review”. Indian Journal
of Pharmaceutical Science & Research. 2013, 3, 1-8.

5. PROCESS OF GASTRIC EMPTYING
Gastric emptying occurs in both fasting and fed states.
Fasting state
Interdigestive
series of electric
event take place.
It cycles both
through stomach
and intestine every
2-3 hrs
It called as
interdigestive
myoelectric cycle
Its having 4
phases Phase 1
Phase2
Phase3
Phase4
ingestion of a mixed
meal
fed state
(digestive motility
pattern)
5
Asha S, Senthil K, Parthiban S. “Bilayer Floating Tablet – A Review”. Indian Journal of
Pharmaceutical Science & Research. 2013, 3, 1-8.

6. •last from 30-60 minutes with rare
contractions.
Phase 1-(Basic
phase)
•last for 20-40 minutes with
intermittent action potentialand
contractions.
Phase 2-
(Preburst
phase)
•last for 10-20 minutes which
includes intense and regular
contractions for short period.
Phase 3-(Burst
phase)
•last for 0-5 minutes and occurs
between phase 2 and 1 of 2
consecutive cycles.Phase 4
6
Desai, S., Bolton, S. “A floating controlled release drug delivery system: in vitro- in vivo
evaluation”. Pharm Res. 1993,10(9), 1321-1325.

7. Floating Drug Delivery System
Effervescent
System
Gas generating
system
Volatile liquid/
vacuum containing
system
Non-Effervescent
System
Single Layer
Floating
Tablet
Bilayer
Floating
Tablet
Alginate
Beads
Hollow/
floating
Microspheres
7Rouge N, Buri P, Doelker E. “Drug absorption sites in the gastrointestinal tract and dosage
forms for site specific delivery”. Int J Pharm. 1996, 136, 117-139.

8. Non Effervescent
System
Single Layer Floating Tablet or
hydrodynamically balanced system
Bilayer Floating Tablet
Alginate Beads
Hollow Microspheres/ Microballoons
8Rouge N, Buri P, Doelker E. “Drug absorption sites in the gastrointestinal tract and dosage
forms for site specific delivery”. Int J Pharm. 1996, 136, 117-139.

9. Granulation 1
Homogeneous Type: Same
drug with different release
pattern
Bilayer
Tablet
Press
COMPRESSION
Granulation 2
Heterogeneous Type: Different
drugs with same or different
release pattern
Sustained release (homogeneous) tablet in which one layer is immediate
release (IR) as initial dose and the second layer is controlled release (CR)
as maintenance dose .
Drug 1 (IR)
Drug 1 (CR)
Drug 1
Drug 2
9
Reddy P, Rao D, Kumar R. 2013. Bilayer technology- an emerging trend: A review.
International Journal of Research and

10. 1
• Effect of Dosage Form Size& Shape
2
• Gender, Posture & Age
3
• Effect of Food & Specific Gravity
4
• Type of Formulation
5
• Nature of Meal & Frequency of Food
10
Sowmya C, Suryaprakash Reddy C, Tabasum SG, Varma V. “An overview on bilayer tablets”.
IJPT, 2012, 2(4), 2143-2156.

11. Enhanced bioavailability
Sustained drug delivery/reduced frequency of dosing
Targeted therapy for local ailments in the upper GIT
Reduced fluctuations of drug concentration Improved
selectivity in receptor activation
Reduced counter-activity of the body
Extended effective concentration.
Minimized adverse activity at the colon
11Reddy P, Rao D, Kumar R. 2013. Bilayer technology- an emerging trend: A review.
International Journal of Research and

12. The drug substances that are unstable in the acidic environment of the
stomach are not suitable candidates to be incorporated in the systems.
These systems require a high level of fluid in the stomach for drug delivery
to float and work efficiently.
Not suitable for drugs that have solubility or stability problem in GIT.
12Reddy P, Rao D, Kumar R. 2013. Bilayer technology- an emerging trend: A review.
International Journal of Research and

13. 13Reddy P, Rao D, Kumar R. 2013. Bilayer technology- an emerging trend: A review.
International Journal of Research and

14. Suitable dosage forms for the drugs those are primarily absorbed in the
stomach.
Beneficial in the treatment of gastric diseases.
Lower dosing and less side effects
To separate incompatible active pharmaceutical ingredients from each other,
to control the release of API from one layer by utilizing the functional
property of other layer (such as osmotic property).
14Naisarg D Pujara, Ronak K Gokani, Jalpa S Paun. “Bilayer tablet – An Emerging Trend”. IJPRD,
2012, 4(4), 102-111

15. MECHANISM OF FDDS
BUOYANCY
FDDS has a bulk density less than gastric fluids
and so remain buoyant in the stomach with out
affecting the gastric emptying rate for a
prolonged period of time.
F = F buoyancy - F gravity = (Df - Ds) gv
Where, F= total vertical force,
Df = fluid density,
Ds = object density,
v = volume and
g = acceleration due to gravity.
15
Desai, S., Bolton, S. “A floating controlled release drug delivery system: in vitro- in vivo
evaluation”. Pharm Res. 1993,10(9), 1321-1325.

16. Compaction
Sieving
Granulates of
API 1/2
Preblending
Blending (API 1)
Lubrication
Blend Layer 1
Compression
layer 1
Dry
granulatio
n
Blendin
g
Tablettin
g
Preblending
Lubrication
Blend Layer 2
Compression layer
2 on layer 1
BILAYER TABLET
HETEROGENEOUS BILAYER TABLET
Simple Compaction and
Ejection
Blending (API 2)
API 1/2
Multiple Compaction and
Ejection
A1 B1 C1 D1 E1
A B C D E
16
Naisarg D Pujara, Ronak K Gokani, Jalpa S Paun. “Bilayer tablet – An Emerging Trend”. IJPRD, 2012, 4(4), 102-111

17. 1.DUREDAS™ TECHNOLOGY (1 Immediate
Release & 1 Controlled Release Layer)
Controlled
release
hydrophilic
swellable matrix
The
controlled
release layer
remain intact
Hydrophilic
polymer start
to swell up by
taking water
from GI fluid
After swelling up,
drug release
occurs in a
controlled release
manner
Immediate
release
layer
Release of the
drug from the
immediate layer
by diffusion
Controlled
release
matrix
DUREDAS™
TECHNOLOGY
(2 Controlled
Release Layers)
[2]
Solvent Influx
Hydrophilic
Polymer
Mixture of
Hydrophilic &
Hydrophobic
Polymer
Hydrophilic
polymer start to
swell up by taking
water from GI fluid
Rate of
swelling is
different for
two layers
Drug release occurs at a
slower rate from the
swollen polymer mixture
Drug
Molecule
17Naisarg D Pujara, Ronak K Gokani, Jalpa S Paun. “Bilayer tablet – An Emerging Trend”. IJPRD, 2012, 4(4), 102-
111

18. 2. OROS® PUSH-
PULL TECHNOLOGY
3. DUROS
TECHNOLOGY
4. PRODAS
TECHNOLOGY [2]
Drug
Layer 1
Drug
Layer 2
Delivery Orifice
Push Layer
Drug
Layer
18Naisarg D Pujara, Ronak K Gokani, Jalpa S Paun. “Bilayer tablet – An Emerging Trend”. IJPRD, 2012, 4(4), 102-
111

19. EVALUATION TESTS
IN-VITRO TEST IN-VIVO TEST
• Floating lag time
• Floating time
• Dissolution study
• Resultant weight test
• X ray method
• Gamma-scintigraphy
• Gastroscopy
• Ultra sonography
19
Panchan HA, Tiwari AK. “A Novel Approach of Bilayer Tablet Technology: A Review”. International
Research Journal of Pharmacy. 2012, 3, 44-49.

20. 20
PRE-COMPRESSION TESTS POSTCOMPRESSION TESTS
Panchan HA, Tiwari AK. “A Novel Approach of Bilayer Tablet Technology: A Review”. International
Research Journal of Pharmacy. 2012, 3, 44-49.

21. 21
Drugs Patent application number
Ciprofloxacin, Acyclovir, Ofloxacin US Patent Appln 2006013876
Heparin and Insulin US Patent Appln 2008153779
Acyclovir, Ganciclovir, Ritonavir, Minocycline, Cimetidine,
Ranitidine, Captopril, Methyldopa, Selegiline, Fexofenadine, US Patent 6120803
Bupropion, Orlistat & Metformin
Ciprofloxacin US Patent Appl 2003232081
Calcitriol, combined with delayed release of a bisphosphonate
calcium resorption inhibitor such as alendronic acid and its salts US Patent Appl 2007104786
and hydrates
PATENT ON FLOATING BILAYER TABLET
Doshi MM, Joshi MD, Mehta .P, inventors, JB. Chemicals & Pharmaceuticals Ltd Pharmaceutical
composition for controlled drug delivery system. US Patent Appl US 2003232081, 2003.

22. 22
ALPRAXPLUS Sertraline, Alprazolam Torrent Pharmaceutcals Ltd.
Glycomet®-GP2Forte Metformin hydrochloride,
USV Limited
Glimepiride
Levocetrizine hydrochloride,
Newcold Plus Phenylpropanolamine, Piramal Healthcare Ltd.
Paracetamol
DIAMICRON®XRNEX500 Gliclazide, Metformin Serdia® Pharmaceuticals
hydrochloride (India) Pvt. Ltd.
DIUCONTIN-K®20/250 Furosemide, Potassium T.C. Health Care Pvt. Ltd.
chloride
TRIOMUNE 30 Nevirapine, Lamivudine,
Cipla Ltd.
Stavudine
PIOKIND®-M15
Pioglitazone, metformine Psychotropics India Ltd.
hydrochloride
Revelol®-Am 25/5 Metoprolol succinate, Ipca Laboratories Ltd.
Amlodipine besilate
COMMERCIALLY MARKETED BILAYER TABLETS

23. floating drug delivery systems have an efficient
means of enhancing the bioavailability and
controlled delivery of many drugs.
Dosage forms with a prolonged GRT will bring
about new and important therapeutic options
The currently available polymer-mediated Non
effervescent and effervescent FDDS, designed on the basis
of delayed gastric emptying and buoyancy principles,
appear to be a very much effective approach to the
modulation of controlled oral drug delivery.
23