Abstract

Ayerst’s data sheet describes this product simply as a sustained-release formulation in gelatin capsules, which misled us into thinking that the capsule was supposed to be the s/r mechanism. Ayerst have now told us that the (ordinary) hard gelatin capsule contains granules with varying numbers of film coats, so that the isosorbide dinitrate is released over a 6-hour period. We wrongly included gelatin capsules among the types of preparation likely to be held up in patients with partial obstruction: hard gelatin readily dissolves.