Abstract: A new crystalline and anhydrous form of doxazosin mesylate is described. The new form is crystalline and anhydrous and is characterized in its X-ray spectrum by the following reflex positions of high and medium intensity: 8.49.degree., 11.72.degree., 16.03.degree., 18.29.degree., 21.03.degree., 22.87.degree. and 25.02.degree.. Owing to its crystalline properties, the new form of doxazosin mesylate according to the invention has surprising advantages both with regard to its synthesis and for pharmaceutical processing into solid dosage forms. A process for preparing the new form of doxazosin mesylate and pharmaceutical compositions comprising the new form of doxazosin mesylate are also described.

Abstract: A new crystalline and anhydrous form of doxazosin mesylate is described. The new form is crystalline and anhydrous and is characterized in its X-ray spectrum by the following reflex positions of high and medium intensity: 10.68.degree., 14.45.degree., 17.37.degree., 23.45.degree., 23.82.degree. and 24.30 .degree.. Owing to its crystalline properties, the new form of doxazosin mesylate according to the invention has surprising advantages both with regard to its synthesis and for pharmaceutical processing into solid dosage forms. A process for preparing the new form of doxazosin mesylate and pharmaceutical compositions comprising the new form of doxazosin mesylate are also described.

Abstract: A new crystalline and anhydrous form of doxazosin mesylate is described. The new form is crystalline and anhydrous and is characterized in its X-ray spectrum by the following reflex positions of high and medium intensity: 15.40.degree., 16.85.degree., 18.06.degree., 24.15.degree. and 25.81.degree.. Owing to its crystalline properties, the new form of doxazosin mesylate according to the invention has surprising advantages both with regard to its synthesis and for pharmaceutical processing into solid dosage forms. A process for preparing the new form of doxazosin mesylate and pharmaceutical compositions comprising the new form of doxazosin mesylate are also described.