Buccal patches

FIG. 8. Schematic diagram showing the design of mucoadhesive buccal patch (from Ref. 105). 

A mucoadhesive buccal patch was evaluated for transmucosal delivery of oxytocin (OT) [103], OT was incorporated with coformulations of Carbopol 974P and silicone polymer. The plasma concentrations of OT remained 20- to 28-fold greater than levels obtained from placebo patches for a period of 0.5 to 3.0 h. 

Wong, C.F., et al. 1999. Formulation and evaluation of controlled release Eudragit buccal patches. Int J Pharm 178 11. 

Li, C., et al. 1997. Transmucosal delivery of oxytocin to rabbits using a mucoadhesive buccal patch. Pharm Dev Technol 2 265. 

A buccal patch comprises a relatively novel dosage form, which is placed in an unconventional drag delivery site. As such, there may be difficulties encountered in trying to get patients to accept this route. It can be imagined that patients may be more reluctant to use a buccal patch in comparison to, for example, a transdermal patch, which has become a well-known and well-established dosage form. 

Special formulations are now in development to provide prolonged mucosal adhesion and sustained delivery of drug through the buccal membrane. Such formulations comprise flexible adhesive patches and films. Important features for drug delivery associated with these novel buccal patches include ... 

Figure 7.3 Types of release possible from a buccal patch...

As discussed above, patient acceptability and comfort requirements dictate that the surface area of a buccal patch is not greater than 15 cm2. The limited surface area available for absorption often means that a penetration enhancer is necessary to ensure ... 

Adequate evaluation of patient acceptability and compliance of buccal patches should include a clinical examination to observe local tolerance, and the incidence and degree of irritation. Trials should also involve the use of questionnaires, in order to determine a subject assessment of such factors as ... 

The size of the delivery system varies with the type of formulation, i.e., a buccal tablet may be approximately 5-8 mm in diameter, whereas a flexible buccal patch may be as large as 10-15 cm in area. Mucoadhesive buccal patches with a surface area of 1-3 cm are most acceptable. It has been estimated that the total amount of drug that can be delivered across the buccal mucosa from a 2-cm system in 1 day is approximately 10-20 mg.f The shape of the delivery system may also vary, although for buccal drug administration, an ellipsoid shape appears to be most acceptable. The thickness of the delivery device is usually restricted to only a few millimeters. The location of the delivery device also needs to be considered. A mucoadhesive retentive system is preferred over a conventional dosage form. A bioadhesive buccal patch would appear to be the most appropriate delivery system because of its flexibility and the area of the buccal mucosa available for its application. The maximal duration of buccal drug retention and absorption is approximately 4-6 h because food and/or liquid intake may require removal of the delivery device. 

Fig. 5 Schematic diagram showing the design of mucoadhe-sive buccal patch. (From Ref 1)...

Merkle, H.P. Anders, R. Wermerskirchen, A. Mucoadhesive buccal patches for peptide delivery. In Bioadhesive Drug Delivery Systems Lenaerts, V., Gurney, R., Eds. CRC Press Boca Raton, PL, 1990 105. 

Li, C. Koch, R.L. Raul, V.A. Bhatt, P.P. Johnston, T.P. Absorption of thyrotropin releasing hormone in rats using a mucoadhesive buccal patch. Drug Dev. Ind. Pharm. 1997, 23, 239-246. 

GRAS listed. Accepted for use as a food additive in Europe. Included in the FDA Inactive Ingredients Guide (oral powder for reconstitution, buccal patch, granules, film-coated, and tablets). Included in nonparenteral medicines licensed in the UK. Included in the Ganadian List of Acceptable Non-medicinal Ingredients. 

Vaughan, D.E., Pharmacokinetics of Albuterol and Butorphanol Administered Intravenously and via a Buccal Patch. 2003, Texas A M University, College Station, TX. 

C.R. Palem, R. Gannu, N. Doodipala, V.V. Yamsani, M.R. Yamsani, Transmucosal dehvery of domperidone from bilayered buccal patches In vitro, ex vivo and in vivo characterization. 

Nafee NA, Boraie MA, Ismail FA, Mortada LM. Design and characterization of mucoadhesive buccal patches containing cetylpyridinium chloride. Acta Pharm. 2003 53(3) 199-212. 

Buccal patches Use Delivery of potent agents. Advantage can occlude surface avoiding loss, tissue permeation enhancers. Issues Cost, potency. 

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