BIOPHARMACEUTICAL EVALUATION OF METHYLCELLULOSE AS AN EXCIPIENT FOR NITROGLYCERIN TABLETS

Abstract

To examine the bioavailability of nitroglycerin in sublingual tablet, 5 healthy adult volunteers underwent simultaneous sublingual administration of a table prepared with methylcellulose and a tablet prepared with lactose containing 0.15 mg of nitroglycerin and 0.15 mg of nitroglycerin-¹⁵N₃, respectively. In 4 of 5 volunteers, no difference in plasma concentration determined by gas chromatography-mass spectrometry (GC-MS) was observed between 2 tablets described above, so it was well accepted that nitroglycerin in tablets prepared with methylcellulose had a similar bioavailability to that in tablets prepared with lactose. The simultaneous administration of the 2 nitroglycerin tablets to a healthy volunteer, one of which containing the drug labeled with a stable isotope followed by GC-MS assay, seems to be the most suitable method for a precise comparison of bioavailability of the formulations.