Buccal administration
[2] Buccal administration of vaccines has been studied, but there are challenges to this approach due to immune tolerance mechanisms that prevent the body from overreacting to immunogens encountered in the course of daily life.
Buccal tablets serve as an alternative drug delivery in patients where compliance is a known issue, including those who are unconscious, nauseated, or having difficulty in swallowing (i.e.
[7] A wide variety of these drugs are available on the market to be prescribed in hospitals and other healthcare settings, including common examples like Corlan, Fentora, and Buccastem.
[8] Buccal tablets are typically formulated through the direct compression of drug, powder mixture, swollen polymer, and other agents that assist in processing.
[8] Buccal tablets offer many advantages in terms of accessibility, ease of administration and withdrawal, and hence may improve patient compliance.
Some cautions and remarks include needing to gargle and spit water once tablet is fully dissolved to minimise risk of oral thrush, prolonged use may lead to withdrawal symptoms, chewing and swallowing of the tablet may limit its efficacy and give rise to additional side effects, and caution with CYP3A4 inhibitors.
Fentanyl is contraindicated in patients hypersensitive to fentanyl, opioid non-tolerant patients, management of acute or postoperative pain, and those with severe hypotension or severe obstructive airway diseases (e.g. COPD) Some cautions include needing to keep tablets out of the sight and reach of children, and must not be sucked, chewed or swallowed.
Side effects typically seen in patients using prochlorperazine maleate tablets include drowsiness, blurred vision, dry mouth, and headache.
Those taking prochlorperazine maleate should avoid exposure to direct sunlight due to photosensitivity and taken certain drugs that are either sedative and give dry mouth (e.g. anticholinergics) or target the heart (e.g. antihypertensives and anticoagulants).
[7] In the oral cavity, buccal tablets potentiate their effect by entering the bloodstream direction through the internal jugular vein into the superior vena cava,[8] avoiding acidic hydrolysis to take place in the gastrointestinal tract.
[8] The physicochemical properties of the drug, for example, its oil/water partition coefficient, molecular weight, structural conformation, determines whether the molecules are transported through the transcellular pathway.
Hence, the excipients of the formulation and the phospholipid bilayer assist in enhancing the diffusion of hydrophilic compounds (i.e. peptides, proteins, macromolecules).
Buccal tablets are rarely used in healthcare settings due to unwanted properties that may limit patient compliance, for example, unpleasant taste and irritation of the oral mucosa.
It is also noted that eating, drinking or smoking should be avoided until the buccal tablet is fully dissolved to prevent drug efficacy changes and concerns of choking.
[7] Conventional dosage forms are unable to ensure therapeutic drug levels in the circulation and the mucosa for mucosal and transmucosal administration because of the washing effect of saliva, and the mechanical stress of the oral cavity.
