This document provides an overview of buccal drug delivery systems. It discusses the advantages like avoiding first-pass metabolism and improved patient compliance. Components of buccal patches like drugs, polymers and permeation enhancers are explained. The manufacturing method of solvent casting and direct milling are described. Evaluation parameters for buccal patches include surface pH, thickness, swelling, and drug release. Examples of marketed buccal patches are also provided.

1. Presented by –
Vedant Kumar Gupta
M.pharm(Pharmaceutics)
2nd Semester(2019-2020)
CSJM UNIVERSITY KANPUR
(UNIVERSITY INSTITUTE OF PHARMACY)
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2. Content
1. INTRODUCTION
2. ADVANTAGES
3. DISADVANTAGES
4. ANATOMY OF BUCCAL CAVITY
5. MUCOADHESION
6. EXAMPLE OF MUCOADHESIVE POLYMER
7. MECHANISMS OF MUCOADHESION
8. THEORIES OF MUCOADHESION
9. FORMULATION OF BDDS
10. COMPONENT OF BUCCAL DRUG DELIVERY SYSTEM
11. MANUFACTURING METHOD
12. EVALUATION OF BUCCAL PATCH
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3. Introduction
 The delivery of drug into systemic
circulation via buccal mucosa i.e. through
the inner lining cheeks is called buccal
drug delivery.
 These dosage forms are placed between
cheeks and upper gums intended purpose
of use is generally treatment of local or
systemic conditions.
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4. Advantages
 Easy to administration.
 Avoids 1st pass metabolism.
 Improved patient compliance due to the elimination of
associated pain with injections.
 Rapid onset of action can be achieved.
 Drugs which are unstable in acidic environment of
stomach can be given by this route.
 Prolongation of contact time with mucosa.
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5. Disadvantages
 Eating and drinking may become restricted.
 Only drug with small dose requirement can be
administered.
 Drug which are unstable at buccal pH can not be
administered by this route.
 Only those drugs which are absorbed by passive
diffusion can be administered by this this route.
 Drug which have a bitter or unpleasant taste , odour ,
can not be administered by this route.
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6. Anatomy of buccal cavity
Fig . 1. cross section view of buccal mucosa
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7. Mucoadhesion
 Mucoadhesive are synthetic or natural polymers which
interact with the mucus layer covering the mucosal
epithelial surface and mucin molecules constituting a
major part of mucus.
 In mucoadhesion two surface are held together by
interfacial forces which may consist of valences, inter
locking action or both.
 Mucoadhesive drug delivery system are delivery system
which utilize the property of bioadhesion of certain
polymers which become adhesive on hydration.
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8. Example of mucoadhesive polymer
 Natural polymers :
Chitosan, xanthum gum, pectin, alginates
 Synthetic polymers :
 Polyacrylic acid derivatives :- Carbopol , Polycarbophil ,
Polyacrylate .
 Cellulose derivatives :- Carboxy methyl cellulose ,
HPMC, Methyl cellulose , Methyl hydroxy ethyl
cellulose
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9. Mechanisms of mucoadhesions
 Mucoadhesions is the attachment of the drug along
with a suitable carrier to the mucous membrane.
Mucoadhesions is a complex phenomenon which
involves –
 Step 1 : Wetting and swelling step occurs when
polymers spreads over the surface of mucosal
membrane to develop intimate contact.
 Swelling of polymer occur because the component of
polymer have an affinity for water.
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10. Cont…
 Step 2 : In this step the mucoadhesive polymer chain
and the mucosal polymer chains intermingle and entrap
to form adhesive bond.
 Strength of bond depends upon the degree of
penetration of the two polymer groups.
 Step 3 : This step involves formation of weak chemicals
bond between the entangled polymer chains.
 Bond includes primary bond such as covalent bond
and secondary interaction such as Vander walls and
hydrogen bonds.
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11. Theories of mucoadhesions
1. The electronic theory
2. The wetting theory
3. The adsorption theory
4. The diffusion theory
5. The mechanical theory
6. The cohesive theory
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12. Formulation of BDDS
Solid dosage
forms
• Tablets
• Patches/Films
• Wafers
• Lozenges
• Powders
Semi solid
dosages forms
• Gels
• Ointments
Liquid dosages
forms
• Sprays
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13. Components of BDDS
1. Drug substance – The drug should have following
characteristics-
 The drug absorption should be passive when given
orally.
 Should be potent.
 MW should be less than 1000 Dalton
 It should be having both nature i.e. hydro-lipophilic
type .
 Non irritant to mucosa .
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14. Cont…
2. Bioadhesive polymer- Bio adhesive polymers play a
major role in buccoadhesive drug delivery system of
drug. Polymers are also used in matrix devices in which
control the duration release of drug. An ideal polymer
for buccoadhesive drug delivery system should have
following characteristics –
 It should be inert and compatible with the environment.
 It should adhere quickly to moist tissue surface.
 The polymer must not be decompose on storage or
during the self life of dosage forms.
 The polymers should be easy available in the market
and economical.
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15. Cont…
3. Backing membrane-
Backing membrane plays a major role in the
attachment to of bioadhesive devices to the mucus
membrane. The materials used as backing membrane
should be inert, and impermeable to the drug and
penetration enhancer. Such impermeable membrane on
buccal bioadhesive patches prevents the drug loss and
offers better patient compliance. The commonly used
materials in backing membrane include carbapol,
magnesium sterate, HPMC, HPC, CMC etc.
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16. Cont…
4. Permeation enhancers-
Substance that facilitate the permeation through buccal
mucosa are referred as permeation enhancers. Selection of
enhancers and its efficacy depends on the physicochemical
properties of the drug , site of administration, nature of
vehicle and other excipient.
Mechanisms of action of permeation:
1. Changing mucus rheology.
2. Increasing the fluidity of lipid bilayer membrane.
3. Acting on component at tight junctions.
4. Increasing the thermodynamic activity of drug.
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17. Manufacturing method
1. Solvent casting:
In this method, all patch excipient including the drug
co-dispersed in a organic solvent and coated onto a sheet of
release liner. After solvent evaporation a thin layer of the
protective backing material in laminated onto the sheet of
coated release liner to form a laminate that is die-cut to
form patches of the desired size and geometry.
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18. Cont…
2. Direct milling:
In this, patch are manufactured without the use of
solvent. Drug and excipients are mechanically mixed by
direct milling , usually without the presence of any liquid.
After the mixing process, the resultant material is rolled on
a release liner until the desired thickness is achieved. The
backing materials is then laminated as previously
described. While there are only minor or even no
differences in patch performance between patches
fabricated by the two processes, the solvent-free process is
preferred because there is no possibility of residual solvent
and associated solvent- elated health issues.
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19. Evaluation of buccal patch
1. Surface pH
2. Thickness measurement
3. Swelling study
4. Folding endurance
5. Morphological characterization
6. Moisture content
7. Film weight
8. Viscosity
9. Disintegration time
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20. Marketed buccal patches
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21. Reference
 Jain NK. Controlled and Novel Drug Delivery, 1st edition,
Published by CBS Publishers and Distributors, New Delhi.
1997; 52-81.
 N.G. Raghvendra Rao, B. Shravani, Mettu Srikanth Reddy
“Overview on Buccal Drug Delivery System” Journal of
Pharmaceutical Sciences and Research Vol. 5(4),2013,80-88
 Reena Sheoran “Buccal Drug Delivery System”Journal of
Pharmaceuticals Sciences and Review Research, 50(1),
May-June 2018,40-46
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