Claims for Patent: 4,822,807

Summary for Patent: 4,822,807

Title:	Pharmaceutical composition containing a stable modification of torasemide
Abstract:	The present invention provides a process for the preparation of cystalline torasemide in the pure modification I (monoclinic, space group P2.sub.1 /c, melting point 162.degree. C.) from torasemide of modification II (monoclinic, space group P2/n, melting point 169.degree. C.), wherein a suspension of torasemide of modification II is stirred in water with the addition of a catalytic amount of modification I until the rearrangement is complete. The present invention also provides pharmaceutical compositions containing torasemide of modification I.
Inventor(s):	Topfmeier; Fritz (Heidelberg, DE), Lettenbauer; Gustav (Lampertheim, DE)
Assignee:	Boehringer Mannheim GmbH (Mannheim, DE)
Application Number:	07/111,439
Patent Claims:	1. A diuretic pharmaceutical composition comprising an effective amount of rapidly dissolving crystalline torasemide of pure modification I (monoclinic, space group P2.sub.1 /c, melting point 169.degree. C.) substantially free of crystalline torasemide of modification II (monoclinic, space group P2/n, melting point 162.degree. C.) and a pharmacologically acceptable carrier, said torasemide of modification I having solubility characteristics such that at least 60% is dissolved in water after 15 minutes, and at least 80% is dissolved in water after 30 minutes. 2. The composition of claim 1 comprising, by weight, approximately: 100 parts of the torasemide of modification I and, as the carrier, 20 parts lactose monohydrate, 77 parts maize starch, 2 parts silicon dioxide and, 1 part magnesium stearate. 3. The composition of claim 1 comprising, by weight, approximately: 25 parts of the torasemide of modification I and, as the carrier, 605 parts lactose monohydrate, 160 parts maize starch, 6 parts silicon dioxide and 4 parts magnesium stearate.