Sublingual Route During Perioperative and Chronic Pain Management

Submit Manuscript | http://medcraveonline.com J Anesth Crit Care Open Access 2015, 3(2): 00085 of first pass metabolism so it provides better bioavailability. It is a non invasive and painless route of administration. It is also suitable for patients with nausea, vomiting, dysphagia, gastrointestinal disturbance such as obstruction. The systemic drug delivery after sublingual route is fast as drug directly reaches in to the blood stream through the reticulated vein on ventral surface of tongue and floor of mouth via facial veins, internal jugular vein, and brachiocephalic vein [3]. It occurs through passive diffusion into the lipoidal membrane of the oral cavity. The sublingually administered drugs are absorbed 3 to 10 times greater as compared to conventional oral route. This is because of high permeability and the rich blood supply of the sublingual region [3]. The drug delivered through the sublingual route needs to have specific properties and is affected by physicochemical properties of the drug and the patient oral condition. The drug should be lipophillic, unionized, soluble in aqueous buccal fluids, binds poorly to mucosa and low molecular weight [1]. The acidic environment due to salivary glands and accompanying vasodilation may also facilitates absorption via sublingual route [3]. The various advantage of sublingual routes includes rapid onset of action. It avoids first pass hepatic metabolism and thus higher bioavailability. The drugs through sublingual route avoids gastric degradation due to pH changes. However sublingual route may not be used for prolonged administration. Sustained drug delivery may not be achieved via this route. It may interfere with eating and drinking during as drug needs to be retained for some time when given via sublingual route. It may also be associated with unpalatability, burning sensation and ulceration. Smoking causes oral vasoconstriction and thus affects the drug absorption [4]. The medical preparation for sublingual administration includes: