摘要 |
a process for the manufacture of pellets which are composed of xanthine derivatives and are predominantly spherical, have a particle sire in the range from 0.3 to 4 mm and have a bulk density above 0.5 g/cm3 by reacting the appropriate xanthine derivative with water or a water/alcohol mixture, entails anhydrous powdered xanthine derivative with an average particle sire of from 20 to 200 .mu.m being suspended by stirring at from 40 to 70.degree.C in a nonsolvent which is immiscible with water and has a boiling point in the range from 60 to 160.degree.C, then adding from 10 to 40 % by weight, based on the anhydrous xanthine derivative, of water or a water/ alcohol mixture and subsequently allowing to cool to room temperature at from 5 to 20.degree.C per hour, it being possible to reduce the stirring speed after agglomeration to about 1/3 to 2/3 of the original, and the pellets being separa- ted from the liquid and dried, the pellets being used, possibly with a delayed release coating, as active compound in a drug.
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