Glyceryl trinitrate buccal

A.J. Pryce, H.F. Heatlie and S.R. Chapman, Buccaling under the pressure influence of secondary care establishments on the prescribing of glyceryl trinitrate buccal tablets in primary care, BMJ 313 (1996), 1621-1624. 

Two sites within the buccal cavity have been used for drug administration. Using the sublingual route, as for glyceryl trinitrate (GTN), the medicament is placed under the tongue, usually in the form of a... 

Nitrates can be administered by various routes. For example, glyceryl trinitrate is used not only as traditional sublingual tablets but also in the form of modified-release tablets, buccal tablets, aerosolized oral spray, intravenous injection, and topical ointment or skin patches for percutaneous absorption (23). These different formulations have been developed largely as a means of controlling the onset and duration of action of glyceryl trinitrate, since in conventional oral form its action is limited by marked hepatic first-pass metabolism. 

An increased frequency of dental caries with the use of buccal glyceryl trinitrate formulations has been reported in Sweden (SEDA-17, 237). 

In an assessment of how nitrate tolerance might be avoided, the efficacy of thrice-daily buccal glyceryl trinitrate and that of four times a day oral isosorbide dinitrate were compared (71) over 2 weeks, prolonged antianginal efficacy was maintained only with thrice-daily buccal administration. Nevertheless, in another study, transdermal glyceryl trinitrate seemed to offer a prolonged effect, sufficient to wean patients with unstable angina from intravenous nitrate therapy (71). 

Glyceryl trinitrate (GTN) is extremely effective at relieving the pain of angina but it has only a short half-life. Due to extensive first pass metabolism the drug is ineffective when taken orally and is administered sublingually or buccally in either tablet or aerosol form. 

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