Enhancement of dissolution property of drugs from ground mixtures with pregelatinized starch

Ground mixtues of hydrocortisone(HC),de-xamethasone acetas(DA)with pregelatinized starch(PGS)were prepared by grinding in a ball mill.The dissolution test in vitro indicated that groundmixture powder gave a higher rate of drug dissolu-tion than physical mixture or intact drug powderand that the dissolution rate of drugs from thetablets prepared with ground mixture powder wasalso significantly greater than that from commercialtablets.The X-ray diffraction patterns and scanningelectron micrographs suggested that when the weightration of drugs with pregelatinized starch was up to1:5,drugs in ground mixture powder were in anamorphous state after 90 min of grinding.Whenground mixture powder was persevered for 3months 37℃ and RH75%,the drug content anddissolution rate in vitro showed no reduction.