This presentation gives a brief overview about buccal drug delivery systems. Though this presentation is not very comprehensive, it touches almost all aspects of the topic and gives the reader a basic and conceptual idea regarding BDDS and familiarizes the viewer with most of its aspects

1. BUCCAL DRUG DELIVERY
SYSTEM
PANKHIL GANDHI

2. GENERAL OVERVIEW
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3. BASIC INTRODUCTION
Buccal drug delivery : the delivery
of drug into systemic circulation
via buccal mucosa i.e. through
the inner lining cheeks is called
buccal drug delivery.
Such dosage forms are placed
between cheeks and upper gums.
Intended purpose of use is
generally treatment of local or
systemic conditions
Potential
route for
drugs that
are:
large
hydrophillic
unstable
Proteins, oligo-
nucleotides,
Poly-
saccharides
Other small
drugs
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4. WHY AND WHEN TO FORMULATE AS
BDDS ?
1. Some drugs have very short half life and therefore need to be
administered multiple times in a day. This reduces patient
compliance.
2. Some drugs may undergo enzymatic degradation in GIT
3. Some drugs suffer great loss in bioavailability as they undergo first
pass metabolism
Due to above mentioned reasons BDDS is employed
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5. ADVANTAGES
1. Easy to administer
2. Therapy can be stopped whenever required
3. For unconscious and trauma patients it is easy to administer
4. Bypass first pass metabolism
5. Drugs unstable in environment of GIT can be given through BDDS
6. Flexibility in physical state, shape, size and surface
7. Rapid onset of action
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6. DISADVANTAGES
1. Cannot administer drugs that are unstable at buccal pH
2. Not suitable for drugs with bitter taste, obnoxious odor, or irritant
to mucosa
3. Only small dose can be administered
4. Eating and drinking may become restricted
5. Only those drugs that are absorbed via passive diffusion can be
given through BDDS
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7. ANATOMY OF BUCCAL
CAVITY
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8. ANATOMY OF BUCCAL
CAVITY
From top to down, following are the
tissues that line the buccal cavity:
1. Mucus membrane
2. Epithelium (stratified/non-stratified)
3. Lamina propria
4. Submucosa
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9. WHY DOES THE PRESENCE OF
KERATIN MATTER?
Keratinised parts:
Mucosae of gingivae and hard
palate
Non-keratinized parts:
Mucosae of soft palate,
sublingual regions and buccal
regions
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Keratinization decreases water
permeability

10. WHAT IS THE ROLE PLAYED BY
SALIVA ?
Absorption of drugs through moist mucosa takes place more readily.
Most drugs administered through BDDS are solids. They must be
first dissolved before they can be absorbed. This is brought out by
saliva
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11. VASCULATURE
drug
Absorbed
through
mucosa
Internal
jugular vein
Superior
vena cava
Heart Entire body
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Liver is by-passed

12. DOSAGE FORMS
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13. Type 1 :
Drug loaded single bioadhesive
layer device. Multidirectional
drug release. Loss due to
swallowing is more
Type 2 :
Double layered device.
Impermeable backing layer on
top. Prevents drug loss from
top surface.
Type 3 :
Every face covered with
impermeable membrane but © PANKHIL GANDHI

14. Matrix type
A buccal patch in the form of a
matrix of adhesive, drug and
other additives
Reservoir type
Buccal patch contains a separate
cavity that contains drug and
additives from the adhesive
membrane.
An impermeable backing is
added on one side and adhesive
membrane on another
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15. 1. Solids – lozenges and tablets. Dissolve in saliva and absorbed from
throughout the oral mucosa
2. Gum – chewing gums. Offers controlled drug delivery over an
extended time. These are very convinient
3. Gel forming liquids and in situ gels
4. Powders – mixture of bioadhesive polymers and drugs sprayed onto
buccal mucosa
5. Patches – attached to buccal region
i. With dissolvable matrix
ii. With non-dissolvable backing
iii. With dissolvable backing
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16. DOSAGE DESIGN AND
FORMULATION
PART 1 – GENERAL
CONSIDERATIONS IN
FORMULATION
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17. PHYSIOLOGICAL CONSIDERATIONS
1. Surface area
2. Device size
3. Drug load
4. Duration
5. Interaction of ingredients with salivary enzymes
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18. PHARMACOLOGICAL
CONSIDERATIONS
1. Lipophilic drugs – absorbed via transcellular route
2. Hydrophilic drugs – absorbed via paracellular routes
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19. PHARMACEUTICAL
CONSIDERATIONS
1. Drug release rate
2. Organoleptic factors
3. Effects of excipients like irritation at site of application
4. Incorporation of penetration enhancers, mucoadhesives, enzyme
inhibitors
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20. DOSAGE DESIGN AND
FORMULATION
PART 2 – BASIC
COMPONENTS
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21. BASIC COMPONENTS OF BDDS :
1. Drug substance
2. Bioadhesive polymers
3. Backing membrane
4. Permeation enhancer
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22. DRUG SUBSTANCE
Prolonged
release
Rapidrelease
Local
action
Systemiceffect
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The drug should have the following
characteristics :
1. Small single dose
2. Fluctuations in blood levels when
given orally
3. Exhibits first pass metabolism
4. Shows passive absorption

23. BIOADHESIVE POLYMER
1. These serve the purpose of
adhering the dosage form to the
buccal region
2. Also employed to form matrix in
which drug is incorporated
3. May be synthetic or natural
4. May be water soluble or insoluble
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24. © PANKHIL GANDHI

25. PERMEATION ENHANCERS
These are the substances that facilitate or enhance the permeation of
the drug through the buccal mucosa
MOA :
1. Reducing the viscosity of mucus
2. Increase fluidity of bilipid membrane
3. Inhibiting various peptidases and proteases in the mucus
membrane to overcome enzymatic barrier
4. Increase solubility of drug
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26. © PANKHIL GANDHI

27. BACKING MEMBRANES
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
carbopol, magnesium stearate, HPMC, HPC, CMC, polycarbophil etc
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28. OTHER ADDITIVES
1. Diluents
2. Sweetening agents
3. Flavouring agents
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29. MANUFACTURING
METHODS
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30. METHODS FOR FILMS/PATCHES
1. Solvent casting
2. Direct milling
3. Hot melt extrusion of films
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31. EVALUATION
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32. MOISTURE ABSORPTION
It gives an indication about the relative moisture absorption capacities
of polymers and an idea whether the buccal patches maintain their
integrity after absorption of moisture.
Patches are placed on agar plates for 2 hr at 37oC.
Moisture absorbed is calculated using the formula:
Initial Weight – Final Weight
% Moisture content =
Initial Weight
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33. SWELLING AND EROSION
Initial Weight – Final Weight
x 100 SI =
Initial Weight
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34. SURFACE PH
Buccal patches are left to swell for 2 hrs on the surface of an agar
plate. The surface pH is measured by means of a pH paper placed on
the surface of the swollen patch.
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35. DETERMINATION OF THE
RESIDENCE TIME
Ex vivo residence time
Ex vivo residence time is determined using a modified USP disintegration
apparatus. It is composed of 800 ml phosphate buffer of pH 6.6 maintained
at 37°C. The porcine buccal tissue is tied to the surface of a glass slab,
vertically attached to the apparatus. The time which was taken for complete
erosion or detachment of the tablet from the mucosal surface was recorded
and considered as ex vivo residence time.
In vivo residence time
The experiment is performed on volunteers. The volunteers are asked to
record the residence time of the film on buccal mucosa in the oral cavity,
which is taken as the time for the patch to dislodge completely from the
buccal mucosa by continual sensation of the patch as well as the backing
membrane.
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36. REFERENCES
1. N.Vidyasagar, et al. , Journal of Pharmaceutical Research and
Development, June 2012, Vol. 1, Issue. 2 , 29 – 35
2. N.G.Raghavendra Rao et al /J. Pharm. Sci. & Res. Vol.5(4), 2013, 80
– 88
3. Patel Mitul et al. , IRJP 2011, 2 (12), 4-11
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