TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): Preparation of crystalline form I of manidipine dihydrochloride comprises (a) dissolving manidipine dihydrochloride in methanol at reflux, (b) cooling the reaction mass to a temperature of 25-30 degrees C, (c) isolating the precipitated crystalline form I of manidipine dihydrochloride and (d) drying under vacuum at 40-45 degrees C for at least 10 hours. Preparation of crystalline form II of manidipine dihydrochloride comprises (a1) dissolving manidipine dihydrochloride in a mixture of methanol and denatured ethanol (1:1) at reflux, the step (b) as above per se, (b1) stirring for 12-14 hours, (c1) isolating the precipitated crystalline form II of manidipine dihydrochloride and the step (d) as above per se. Preparation of crystalline form III of manidipine dihydrochloride, comprises (a2) dissolving manidipine dihydrochloride in a mixture of methanol and toluene (1:1) at 75-80 degrees C, the step (b) and (b1), as above per se, isolating the precipitated crystalline Form III of manidipine dihydrochloride and the step (d) as above per se. Preparation of crystalline form IV of manidipine dihydrochloride comprises dissolving manidipine dihydrochloride in a mixture of toluene and denatured ethanol (1:1) at 75-80 degrees C, the step (b) and (b1) as above per se, isolating the precipitated crystalline form IV of manidipine dihydrochloride and the step (d) as above per se. Preparation of amorphous form (V) of manidipine dihydrochloride comprises the step (a) as above per se, concentrating under vacuum to dryness, isolating the precipitated amorphous manidipine dihydrochloride and the step (d) as above per se. Preparation of crystalline form VI of manidipine base comprises dissolving manidipine base in methanol at reflux, the step (b) as above per se, adding n-heptane under stirring, stirring for 10-12 hours, isolating the precipitated crystalline form VI of manidipine base and the step (d) as above per se. Preparation of amorphous manidipine base comprises dissolving methylene dichloride at 40 degrees C, concentrating under vacuum to dryness, isolating the precipitated amorphous manidipine base and the step (d) as above per se. Preferred Components: The manidipine dihydrochloride used to prepare the forms of I-IV manidipine dihydrochloride and its amorphous form V including its base forms VI and VII, is in any polymorphic form or in a mixture of any polymorphic forms. ACTIVITY - Antiinflammatory; Hypotensive.    MECHANISM OF ACTION - Dihydropyridine calcium channel antagonist.    EXAMPLE - Manidipine dihydrochloride (16 g) was dissolved in methanol (320 ml) at 65 degrees C. The solution was cooled to room temperature with constant stirring for 4 hours. The solid obtained was filtered, washed with methanol and dried under vacuum at 40-45 degrees C for 10-12 hours to give crystalline form I of manidipine dihydrochloride (purity 99.81%).