3. Since the early 1980, the concept of mucoadhesion has gained interest
in pharmaceutical technology.
MDDS have been developed for buccal, nasal, rectal, & vaginal routes
for systemic & local effect.
Definition- MDDS interact with mucus layer covering the mucosal
epithelial surface, & mucin molecules & increases the residence
time of the dosage form at the site of absorption.
• It is a part of controlled delivery system.
• Mucoadhesion is used when the bond is formed with a mucosal
surface.
• While the term cytoadhesion means adhesion with the cells.
• Hydrophilic high mol.wt subs. Such as peptides that cannot be
administrated & poor absorption then MDDS is best choice.
4. 1. Prolong the residence time of the dosage
form.
2. Improve the therapeutic performance of
drug.
3. Does not cause irritation.
4. High drug loading capacity.
5. Controlled drug release.
6. Decreases side effect.
5. 1. The rapid adherence to mucosal layer without
any change in physical property of delivery
matrix.
2. Minimum interference to the release of active
agent.
3. Biodegradable without producing any toxic by-
products.
4. Enhance the penetration of the active agent.
6. It is complex process involving –
Step 1- Wetting & swelling of polymer (contact stage).
Occurs when polymer spreads over biological surface.
This can be readily achieved for placing a formulation i.e., tablet, paste within the oral cavity.
Swelling of polymers occurs because the compound within the polymer have affinity towards
water.
Step 2 – Interpenetration between the polymer chain & the mucosal membrane.
Surface of mucosal membrane is composed of high mole. Weight polymer know as
glycoprotein.
The polymer chain & the mucosal polymer chain interact & entangle to form semi permeable
adhesive bonds.
In order to from strong adhesive bond.
7. Step 3- Formation of chemical bonds between the entangled chain (consolidation
stage).
Involves formation of weak chemical bonds between the entangle polymer chain.
This chemical bonds involves primary force i.e. covalent bond & weaker secondary bond
i.e. van der waal interaction & hydrogen bond.
Both bond are exploited in the manuf. of mucoadhesive formulation.
Strong adhesions between polymers are formed.
8. Route of administration MDDS formulation
Oral cavity (buccal &
sublingual)
Tablet, patch, gel, ointment, chewing gums.
Nasal Gel.
ocular Insert, gel.
GI Gel, tablet, microspheres, capsules.
vaginal Gel, tablet, microspheres, capsules.
There are various formulation they are as follows-
rectal Gel.
9. 1. Tablet-
Small, flat, oval, formulation.
They soften, adhere to the mucosa & retain in position
& dissolution/release is complete.
Drug is practically coated with polymer.
E.g.- cellulose ether
Acrylic polymer
Sodium alginate
Adv –offer efficient absorption & enhance bioavailability
due to higher contact time.
10.
11. 2. Patches-
Several different patches system are designed to deliver drug has been developed
They are patches with a dissolvable matrix for drug delivery to oral cavity.
Adv- longer acting than solid formulation(tablet).
Uses- it is used in treatment of candidiasis.
12. 3. Chewing gums- bases consist of elastomers, resins, fats antioxidant.
E.g.-Nicorette gum.
4. Gels & ointments
They are semisolid dosage forms.
Adv- easy dispersion throughout oral mucosa.
Disadv-may not be accurate than that of tablets.
Poor retention of gel at site of application.
But this has been overcome by using mucoadhesive formulation (polymer).
E.g.-sodium carboxymethylcellulose
Hyaluronic acid
Xanthan gum
They undergo phase change from liquid semisolid.
13. Drug and powder are in form of fine powder dissolved in an aq. & non- aq. Bases. Applied
using finger.
E.g.- mouth ulcer gels.
5. Sprays-
Capable of delivering large molecules.
E.g.- insulin across oral mucosa
Glyceryl trinitrates(small molecule) across sublingual oral mucosa.
6. Paste-
Used in delivery of antimicrobial agents
Also used in local delivery & retention of slow release minocycline.
14. Prolongs the residence time of the dosage form
Excellent accessibility, rapid onset of action possible.
Rapid absorption because of good perfusion rate.
Better patient compliance, ease of drug administration.
Rapid cellular recovery and healing of local site.
Reduced dosing frequency.
Shorter treatment period.
Faster onset of action is achieved due to mucosal surface.
Increased safety margin.
15. Drugs which irritate the oral mucosa, have a bitter or unpleasant taste,
odour, cannot be administrated by this route.
Only drug with small dose can be adm.
Eat and drinking may be restricted.
It may get dislodged.
Drugs, which are unstable at buccal ph, cannot be adm. By this route.