A Seminar OnMUCOADHESIVE DRUD DELIVERY SYSTEM Presented By SONAM M.GANDHI Department of Industrial Pharmacy
INTRODUCTION DEFINITION:• It may be defined as a drug delivery system which utilize property of bioadhesion of certain water soluble polymers which become adhesive on hydration and hence can be used for targeting a drug to a particular region of the body for extended periods of time. ADVANTAGES:• First pass elimination associated with oral administration , so increase the bioavaibility and therapeutic activity.• Both lipophilic and hydrophilic drug can be permeated.
TYPES OF MUCOADHESIVE DRUG DELIVERY SYSTEM ORAL BUCCALVAGINAL MUCOADHESIVE RECTAL NASAL OCULAR
Buccal drug delivery system Drug delivery according to membranes of oral cavity:A. Sublingual delivery: The membrane of tongue and the floor of the mouth. Administration of drug via sublingual mucosa to systemic circulation.B. Buccal delivery: The lining of cheeck. Administration of drug via buccal mucosa to the systemic circulation.C. Local delivery:for the treatment of condition of the oral cavity. Eg. Apthous ulcer, fungal condition
ADVANTAGES OF BUCCAL DELIVERY1. Bypasses the hepatic first pass metabolism and greater bioavailability.2. Delivery device can be made unidirectional: only oral mucosal absorption.3. Buccal mucosa is less prone to damage or irritation than oral mucosa.4. Extent of perfusion is more , therefore quick and effective.5. Nausea and vomiting are greatly avoided.6. Used in case of unconscious and less co-operative patients.7. It offers a passive system, which does not require activation and the therapeutic serum concentration can be achieved rapidly. •less packing cost •Less transport cost8. Since the formulation is light: •Economy of raw material •cheap
DISADVANTAGES1. Relatively smaller area of absorption2. The thickness of delivery system should be limited to a few millimeter in order to avoid inconveniences for patient.3. Part of drug may be dissolve in saliva and may be swallowed.4. Drugs which irritate oral mucosa or have bitter taste cause allergic reaction , discoloration teeth cannot be formulated.5. If formulation contains antimicrobial agents, affect the natural microbial flora of mouth.6. The patient cannot eat or drink or speak.7. Only those drugs which are absorbed by passive diffusion can be administered by this route.8. Drugs which are unstable at buccal pH cannot be administered by this route.
STRUCTURE OF ORAL MUCOSA Oral cavity containing The floor of mouth Buccal mucous The inner side of lips The mucous membranes have a total area of 100 cm2 Blood supply to the oral tissue is delivered principally via the external carotid artery. The thickness of the epithelium varies considerably between sites, the mucosa measures 500-800 μm
TRANSMUCOSAL PERMEATION• MECHANISM: Two route involve in drug permeation across epithelial membrane.1) Paracellular route 2) Transcellular route1) Paracellular route: For hydrophilic compound.• This compound is difficult to penetrate into the lipopholic cell membrane• Intercellular space is preferred route for drug transport• Drug movement in this route (JH) can be written as: JH = DH ε CD where ε fraction of surface area of paracellular route hH DH diffusion coefficient hH pathlength of paracellular route CD is the donar side drug concentration
2) Transcellular route: For lipophilic compound Drug molecule move across both lipophilic cell membrane and hydrophilic cytoplasm as well as intercellular space. The permeability of lipophilic compound across the epithelial cell membrane is typically high. Drug flux in transcellular route (JL) can be expressed as: JL= (1- ε ) DH KP CD hL where KP is the partition coefficient between lipophilic and hydrophilic region, h L is pathlength of transcellular route.
MECHANISM AND KINETIC OF TRANSMUCOSAL PERMEATION• Determine by using progesterone as the modal lipophilic molecule and Mannitol as model hydrophilic molecule was studied using mucosal membrane rabbit• Both lipophilic and hydrophilic drug are capable of permeating through all mucosal membranes at zero order kinetic.• Nasal mucosa showing a significantly higher rate of permiation and a shorter lag time than that rectal and vaginal mucosae. The duration of lag time was noted to increase in the order : Nasal < Rectal < vaginal mucosa Mucosal membrane Thickness (µm) Oral mucosa• Buccal 594• sublingual 111 Nasal mucosa 53.5 Rectal mucos 175.3 Vaginal mucosa 165.1
PERMIATION ENHANCER BioavibilityPermeation enhancer are added to increase Absorption rate Membrane permiationEnhancer efficasy depends on: Physicochemical properties of the drug Administration site Nature of the vehicle Enzymatic activity Lipid composition Cellular morphology Potential protein interaction Membrane thickness Enhancer use alone or in combination
LIST OF MEMBRANE PERMIATION ENHANCER:a) Bile salt and other steroidal detergent: Sodium glycocholate Sodium taurocholate Saponins sodium taurodihydrofusidate Sodium glycodihydrofusidate c) Other enhancersb) Surfactants: Azone1. Nonnionics: Salicylates Polysorbat 80 sulfoxides Sucrose ester2. Cationic: Diethyltrimethyl ammonium bromide3. Anionic Sodiume lauryl sulphat