The Compound Norcantharidin Floating Sustain Releasing Tablet

The compound norcantharidin floating sustain releasing tablet(CNRT) which consisted of norcantharindin,Milkvetch Root and Common Bletilla Tuber prolongs the time of treatment in the lesion location of gastric cancer patients and improves effect.Milkvetch Root of three granule diameters were extracted by water-alcohol co-distilling technology,cellulase degradation,calcarea solution,ultrasonic waves methods respectively.The extracts were purified by ultrafiltration and Macro Absorption Resin.The yield coefficient is about 3.55%,volume of extractive is reduced 9%and 24%respectively than the alcohol and water extractive.Common Bletilla Tuber of three granule diameters were used to test the albino rat gastric ulcer by anhydrous alcohol and acetic acid inhibiting effect.The Common Bletilla Tuber power can decrease significantly the GU area,and the dosage of Common Bletilla Tuber ultramicro powder,at the same effect,was 1/3 of normal.We adopted hydrophilic sustained-release matrix and orthogonal design method to optimize the formulation of the compound norcantharidin floating sustain releasing tablet.We reviewed other factors which affected drug release of this medicine.By comparing the six aspects of process,appearance of the tablets,floating ability and release characteristics,an optimized formulation was chosen to float within 3 minutes in vitro and continuing over 8 hours on simulated gastric fluid,and 7-10 hours releasing 75%.Drawing up the standard of floating tablet.According to the isotope tracer technique,the process of tablet remained in stomach was observed.In vivo,floating 2-3 hours on limosis,4-5 hours on a full stomach.We selected norcantharidin as index to probe into pharmacokinetics and bioavailability in dog.The result shows the compound norcantharidin floating sustain releasing tablet can increase the local drug concentration,bioavailability is 221.8%of normal tablet.The half-life prolongs 2.7 hours,detention time in vivo prolong 5 hours, can reduce the dosage,reduces toxic,side effect and reduce the times of administration.This tablet is capable of remaining buoyant on gastric fluid,it can achieve aim to sustained-release,detention time in vivo is obviously prolonged,the bioavailability of norcantharidin is enhaced evidently.