Buccal administration is a way of delivering medication by placing it against the inner lining of your cheek, where it dissolves and absorbs directly into your bloodstream. Instead of swallowing a pill and waiting for it to pass through your stomach and liver, the drug crosses through the thin tissue of your cheek and enters circulation almost immediately. It’s used for pain management, hormone therapy, antiviral treatment, and other situations where faster or more reliable absorption matters.
How Buccal Absorption Works
The inside of your cheek is lined with a soft, non-keratinized tissue called the buccal mucosa. It’s only about 0.5 to 0.8 millimeters thick and covers roughly 50 square centimeters of surface area in an adult. That thin tissue is rich with blood vessels, which is the key to the whole process: when a drug dissolves against your cheek, it passes through the tissue lining and enters the bloodstream through veins that drain directly into general circulation.
This matters because of something called first-pass metabolism. When you swallow a conventional pill, it travels to your stomach, gets absorbed through your intestines, and then passes through your liver before reaching the rest of your body. The liver breaks down a significant portion of many drugs before they ever have a chance to work. Buccal delivery skips that entire journey. The drug enters your blood through the external jugular vein, bypassing both the digestive tract and the liver. The result is that more of the active drug reaches your system, and it gets there faster.
The cheek lining also has relatively low enzyme activity compared to the gut, so the drug faces less chemical breakdown during absorption. This is especially important for medications like steroids and certain peptides that would be largely destroyed by stomach acid or liver enzymes if swallowed.
Buccal vs. Sublingual Delivery
People often confuse buccal and sublingual administration because both happen inside the mouth. The difference is placement: buccal means against the cheek, sublingual means under the tongue. Both routes bypass the liver and digestive system, but they aren’t identical.
The tissue under the tongue is thinner and slightly more permeable. Research shows the sublingual epithelium can allow molecules as large as 70 kilodaltons to pass through, while the buccal lining tops out at roughly 20 to 40 kilodaltons. That makes sublingual delivery better suited for drugs that need to absorb very quickly, like nitroglycerin for chest pain. Buccal delivery, on the other hand, offers a larger and more stable surface area. A tablet or film placed against the cheek can stay in place for an extended period without being dislodged by tongue movement or saliva, making it better for sustained or controlled-release medications.
How to Use Buccal Medications
Proper placement is straightforward but important. You gently pull back one side of your mouth and position the tablet or film between your gum and inner cheek. Then you hold still and let it dissolve completely. You should not crush, chew, break, or swallow the medication, as doing so can reduce its effectiveness and potentially cause side effects from the drug hitting your stomach all at once instead of absorbing gradually.
For someone who can’t hold the medication in place (a young child, for instance), lying on one side with the cheek facing down lets gravity keep the medication against the tissue. Liquid buccal formulations can also be administered this way. Most buccal medications are designed so you can still talk and drink water while they dissolve, though specific instructions vary by product.
Types of Buccal Dosage Forms
Buccal medications come in several formats, each designed to stick to the moist cheek lining and release the drug at a controlled rate:
- Tablets: Small, flat, and oval, typically 5 to 8 millimeters across. They soften on contact with saliva, adhere to the mucosa, and stay in place until they fully dissolve. These are the most common form.
- Films and patches: Thin, flexible strips that conform to the cheek more comfortably than a tablet. Patches often include a backing layer that prevents the drug from leaking into the mouth, directing all absorption toward the cheek tissue. Many patients find films more comfortable for extended wear.
- Sprays: Less common but used for certain medications like nitroglycerin. These deliver a fine mist against the cheek lining for rapid absorption.
Common Buccal Medications
Several FDA-approved medications use the buccal route. Fentora (fentanyl buccal tablets) is prescribed for breakthrough cancer pain in patients who are already tolerant to opioids, where rapid onset is critical. Belbuca (buprenorphine buccal film) is used for chronic pain management and delivers the drug through a dissolvable film placed inside the cheek. Sitavig (acyclovir buccal tablets) treats cold sores caused by herpes simplex virus, delivering the antiviral drug directly to the oral tissue where the infection occurs.
These examples illustrate the range of buccal delivery: some medications use the route for speed, others for sustained release, and others for local treatment right at the site of application.
Advantages Over Swallowed Medications
The biggest advantage is bypassing liver metabolism. For drugs that the liver would heavily break down, buccal delivery can dramatically increase the amount of active drug that actually reaches your system. This means lower doses can achieve the same effect, which often translates to fewer side effects.
Buccal delivery is also non-invasive, unlike injections, and doesn’t depend on a functioning digestive system. This makes it useful for patients who have nausea, vomiting, difficulty swallowing, or gastrointestinal conditions that interfere with normal absorption. The cheek lining is also easily accessible and repairs itself quickly, so mild irritation from repeated use typically resolves on its own.
Limitations of Buccal Delivery
Not every drug works well through the cheek. The buccal mucosa acts as a barrier through layers of lipids (fats) packed between cells, and large molecules have a hard time crossing it. The practical permeability limit sits around 20 to 40 kilodaltons, which means many proteins and large peptide drugs simply can’t pass through efficiently without chemical enhancers to help them along.
Saliva is another challenge. It constantly washes over the cheek, which can dissolve the medication before it fully absorbs or dilute it enough to reduce effectiveness. This is why buccal formulations use mucoadhesive materials that grip the tissue and resist being washed away. Even so, eating, drinking, or talking too much during absorption can interfere with delivery. The relatively small surface area of the cheek, compared to the intestinal lining, also limits how much drug can be absorbed at once, making buccal delivery impractical for medications that require very large doses.