BMDDS

BY : JAIDEEP SARKAR

INTRODUCTIONBuccomucosal routes of drug delivery involves the delivery of the drug through the mucosal linings of the oral cavity

The oral mucosa is composed of

1.outermost layer : stratified squamous epithelium. 2.basement membrane : lamina propria.

3.innermost layer : submucosa.

The permeability of buccal mucosa is 4 - 4000 times greater than that of skin.

ENVIRONMENT AND ROLE OF BUCCAL MUCOSA

The cells of the oral epithelia are surrounded by an intercellular ground substance, mucus which is a part of saliva secreted by salivary glands

Bioadhesion of mucoadhesive drug delivery systems Cell-cell adhesion Lubrication

DRUG DELIVERY PATHWAYS

Two possible routes of drug absorption through oral mucosa

BUCCAL DRUG DELIVERY AND MUCOADHESIVITY

Mucoadhesion of the device is a key element

The term ‘mucoadhesive’ is commonly used for materials that bind to the cumin layer of a biological membrane

Based on the molecular interactions

The molecular interactions composed of attractive and repulsive forces

For muco adhesion to occur, the attractive interaction should be larger than repulsions.

MECHANISM OF BIOADHESIVE FOR MUCOSAL DRUG DELIVERY

Bioadhesive polymer chains

Mucus polymer chains

FUSION OF MUCUS LAYER AND BIOADHESIVE POLYMER

APPROACHING POLYMERS

MUCOADHESIVE POLYMERS

GENERAL PHYSIOCHEMICAL FEATURES

Predominantly anionic hydrophilicity , suitable surface property, sufficient flexibility

Carboxymethyl cellulose

Carbopol Polycarbophil

Sodium Alginate Hydroxyethyl cellulose Hydroxypropyl methylcellulose

Chitosan Gelatin Pectin

BUCCAL MUCOADHESIVE DOSAGE FORMS

Three types based on their geometry

DESIGN OF BUCCAL DOSAGE FORM

•Matrix type: The Buccal patch designed in a matrix configuration contains drug, adhesive, and additives mixed together

Bi-directional patches release drug in both the mucosa and the mouth

Drug + Mucoadhesive Matrix………………………………………………………………….………………………………………………………………….

Contd…

• Reserviour type: The buccal patch designed in a reservoir system contains a cavity for the drug and additives separate from the adhesive

Impermeable backing is applied to control the direction of drug delivery; to reduce patch deformation and disintegration while in the mouth; and to prevent drug loss

Backing Layer

Drug + Mucoadhesive Matrix

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ACTIVE INGREDIENTS DELIVERED VIA A BUCCAL ROUTE

MARKET FORMULATIONS

RECENT & FUTURE OF BDDS

Buccal nitroglycerin, is used for acute therapy for an anginal attack as well as for chronic prophylaxis

Novel liquid aerosol formulation of insulin

Buccal delivery of drugs that undergo a first-pass effect, such as cardiovascular drugs, analgesics, and peptides

Promote further research; more companies

Rest depend on delivery technology

THIS RECENT SCAN IMAGE OF

PFIZER PROVES THAT BMDDS HAS SYSTEMIC EFFECT AND SO IS BENEFICIAL FOR THOSE PATIENTS THAT ARE UNCOOPERATIVE FOR OTHER DOSAGE FORM

ADVANTAGES

Avoids first pass effect, hostility of GIT Abundance of blood vessel, fast cellular recovery Since the formulation is light so less packing cost, transport cost, economy of raw material and cheap Ease of administration and termination Rapid absorption possible & hence relatively rapid onset of action Directly & easily modify microenvironment Lower intersubject variability as compared to transdermal patches as stratum corneum is absent

DISADVANTAGES Relatively small absorptive surface area (0.01 sq m vs 100 sq m for

GIT)

Movement affects mucoadhesive systems

Less permeable than the small intestine

Salivation and swallowing

Taste of the drug

If formulation contains antimicrobial agents, affects the natural microbes in the buccal cavity.

The patient cannot eat/drink/speak.

CONCLUSION

Buccal drug delivery is a promising area for systemic delivery of orally inefficient drugs as well as an attractive alternative for noninvasive delivery by buccal films, buccal patches, gels and tablets.

With the influx of a large number of new drug molecules from drug discovery, mucoadhesive drug delivery will play an even more important role in delivering these molecules.