Glyceryl trinitrate sublingual

Several studies have now reinforced the concept that endothelial dysfunction is the common denominator for ED and CAD (9), In one study 30 men with Doppler proven ED and no clinical evidence of cardiovascular disease (mean age, 46 years) were compared with 27 healthy age matched controls using flow-mediated brachial artery vasodilatation studies (23). The men with ED exhibited significantly lower brachial artery flow-mediated endothelium dependent vasodilatation (p < 0,05, Fig, 3) and endothelium-independent vasodilatation judged by a blunted response to 0.4 mg glyceryl trinitrate sublingually (p = 0,02), Looking at biochemical markers P-selection,... 

Dose. Usually the equivalent of 0.5 to 1 mg of glyceryl trinitrate sublingually, repeated as required doses of 5.2 to 38.4 mg daily are given by mouth as sustained-release tablets. 

For immediate pre-exertional prophylaxis glyceryl trinitrate sublingually or nifedipine (bite the capsule and hold the liquid in the mouth or swallow it). 

Glyceryl trinitrate Sublingual Spray Glytrin Sanofi-Aventis... 

Q66 When d ispensing sublingual glyceryl trinitrate tablets to a patient, they should be advised to ... 

Forced dilatation at endoscopy or surgical cardiomy-otomy are the treatments of choice, although injection of botulinum toxin (which needs repetition) is also effective. Temporary relief can, be obtained with sublingual or inhaled glyceryl trinitrate. 

After sublingual administration of 0.3 mg to 1 subject, a blood concentration of about 0.001 ag/ml was attained in 3 minutes following an oral dose of 6.5 mg or application of an ointment containing 16 mg of glyceryl trinitrate to the same subject, peak blood concentrations of about... 

Advantages are that quick effect is obtained, e.g. with glyceryl trinitrate as an aerosol spray, or as sublingual tablets which can be chewed, giving greater surface area for solution. Spitting out the tablet will terminate the effect. 

Reduction of portal pressure. Vasopressin (anti-duiretic hormone, see p. 711), in addition to its action on the renal collecting ducts (through receptors), constricts smooth muscle (Vj receptors) in the cardiovascular system (hence its name), and particularly in splanchnic blood vessels, so reducing blood flow in the portal venous system. Unfortunately, coronary vasoconstriction can also occur, and treatment has to be withdrawn from 20% of patients because of myocardial ischaemia. Glyceryl trinitrate (transdermally, sublingually, or intravenously) reduces the cardiac risk and, advantageously, further reduces portal venous resistance and pressure. 

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. 

Hypotension is a frequent adverse effect of nitrates (24), resulting from dilatation of arteries and veins. It can be associated with reflex tachycardia and palpitation, and even syncope on assuming an upright posture. Hypotension occurs particularly in old people, especially those with recurrent falls (SEDA-16, 196), and more commonly with glyceryl trinitrate oral spray than with sublingual tablets, because of its faster onset of action (24). It tends to occur more commonly in those who take nitrates infrequently. 

Glyceryl trinitrate in sublingual tablets causes a burning sensation under the tongue, an indication of the activity of the formulation. Altered and later absent taste sensation developed in a patient taking long-term transdermal glyceryl trinitrate patches (15). 

Alcohol potentiates the hypotensive effects of sublingual glyceryl trinitrate (99). 

The pressure-lowering effect of a step-wise intravenous infusion of glyceryl trinitrate was significantly increased in 12 healthy volunteers treated for 4 days with sildenafil (Viagra) 25 mg tds episodes of symptomatic hjrpotension were also more frequent with sildenafil (113). When sublingual glyceryl trinitrate was used, the reduction in systolic blood pressure was four-fold greater in association with sildenafil. 

Craig S, Dalton R, Tuck M, Brew F. Sublingual glyceryl trinitrate for uterine relaxation at Caeserean section—a prospective trial. Aust NZ J Obstet Gynaecol 1998 38(l) 34-9. 

Diltiazem is metabolized by CYP3A4 and was held responsible for unanticipated prolonged hypotension after sublingual glyceryl trinitrate in a patient who underwent coronary angiography 2 days after last using sildenafil (47). 

Nitroglycerin (glyceryl trinitrate) possesses a nitrate ester bond that undergoes biotransformation by unknown mechanisms to form nitric oxide. The drug can be given orally, transdermally, sublingually and i.v. 

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