SCINTIGRAPHIC AND PHARMACOKINETIC ASSESSMENT OF A MULTIPARTICULATE SUSTAINED-RELEASE FORMULATION OF DILTIAZEM

The in vivo behaviour of a sustained release multiparticulate form of diltiazem (240 mg) has been evaluated by gamma scintigraphy in eight subjects under fasting or fed conditions. The gastric emptying of the pellet formulation was significantly influenced by the presence of food. Transit through the small intestine was unaffected by food and in the majority of cases, the formulation reached the caecum about 3-4 h after leaving the stomach. Post-prandial administration of the sustained release pellet formulation did not affect the bioavailability of the drug. The type of oral formulation (i.e. solution or pellets) appeared to affect the rate, but not the extent, of absorption with the relative bioavailability (pellets to solution) being greater than 90%.