A Review on Sublingual Tablets: An Efficient Alternative for Drug Administration

Oral mucosal drug delivery is a novel route for systemic drug delivery, which not only has many advantages but also has many potentials. Sublingual, meaning "under the tongue," is the method of drug administration in which the drug substance is placed under the tongue alone for rapid absorption through the vessels beneath the tongue. The sublingual route bypasses hepatic first-pass metabolic processes, which results in better bioavailability, faster onset of action, and greater patient compliance. If sublingual medications are used, the onset of action is faster than that expected for orally administered tablets. Sublingual tablets disintegrate quickly, and very little saliva secretion is usually enough for rapid disintegration along with good dissolution and great bioavailability. The mechanism of action provided by sublingual tablets involves placing a tablet under the tongue, where it rapidly dissolves in saliva and allows the active pharmaceutical ingredients to pass through the sublingual mucosa directly into the systemic circulation. This causes the drug to avoid the gastrointestinal tract and liver first-pass metabolism, resulting in a faster onset of action with more predictable therapeutic effects. Sublingual tablets find their best use in drugs which require instant therapeutic responses such as cardiovascular conditions, pain management, and acute conditions such as angina. Important formulation parameters include drug solubility, stability, taste masking, and the use of excipients to promote their release from the formulation. Developments in science and technology have enhanced the application of this dosage form by introducing innovations such as the fast-dissolving and controlled-release systems.