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

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

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

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

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

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

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