1. Buccal and sublingual administration
Tablets to be placed under the tongue or in the cheek pouch and retained in the mouth
Highly vascular epithelium
Ideal for: lipid soluble drugs, high metabolism in the GIT or liver after oral administration
Oral mucosa resembles the skin more than the GIT
Oral mucosa: two areas:
Non keratinized area: floor of the mouth, buccal mucosa
Keratinized mucosa: gum, hard palate, inner side of the lips

2. Cohesion is by lipids and glycolipids
Buccal mucosa is composed of 2 components: epithelium and connective tissue
Rapid turnover of the cells
Non keratinized squamous cells with different degrees of maturity
Cohesion is by lipids and glycolipids

3. Absorption is mainly by passive diffusion and it obeys pH partition hypothesis
Lipid solubility and absorption
Nitroglycerine tablets
Nicotine chewing gum

4. Buccal mucosa is composed of 2 components: epithelium and connective tissue
Rapid turnover of the cells
Non keratinized squamous cells with different degrees of maturity

5. Absorption of peptides and proteins
Barriers ?
Transport: intracellular, intercellular
Buccal mucosa and enzymes: low levels of membrane associated enzymes

6. Approaches to improve permeation
Increase the lipophilicity of the peptide
Lipophilic carriers
Absorption enhancers
In vitro models for testing
Cell lines
Animal models

7. Penetration enhancers used in Buccal Delivery Chelators: EDTA, citric acid, sodium salicylate, methoxy salicylates. Surfactants: sodium lauryl sulphate, polyoxyethylene, Polyoxyethylene-9-laurylether, Polyoxythylene-20-cetylethe. Benzalkonium chloride, 23-lauryl ether, Bile salts: sodium glycocholate, sodium deoxycholate, sodium taurocholate, sodium glycodeoxycholate, Fatty acids: oleic acid, capric acid, lauric acid, lauric acid/propylene glycol. Inclusion complexes: cyclodextrins. Thiolated polymers: chitosan-4-thiobutylamide, chitosan-4-thiobutylamide/GSH, chitosan-cysteine, Poly (acrylicacid)-homocysteine Mechanisms of enhancing permeation Changing mucus rheology Increasing the fluidity of lipid bilayer membrane Acting on the components at tight junctions By overcoming the enzymatic barrier