Grdds ppt
- 1. GASTRORETENTIVE DRUG DELIVERY SYSTEM PRESENTED BY, SHITAL S. SHEWALE. M . Pharm first year Dept . of pharmaceutics Rajarambapu college of pharmacy, kasegaon
- 3. INTRODUCTION • Conventional oral drug delivery system (DDS) is complicated by limited gastric residence time (GRT). • Rapid GI transit can prevent complete drug release in absorption zone & reduce the efficacy of the administered dose since the majority of drugs are absorbed in stomach or the upper part of small intestine.
- 4. • Among the GRDDS, floating drug delivery system have been the most commonly used. • Gastro-retentive delivery is one of the site specific delivery of the drugs at stomach. It is obtained by retaining dosage form into stomach and drug is being released at sustained manner to specific site either in stomach or intestine.
- 5. ADVANTAGES • Longer residence time in stomach could be advantages for local action in stomach. • Bioavailability can be improved. • Site specific delivery. • Minimize the fluctuation of drug concentration.
- 6. Candidates of GRDDS • Drugs acting locally in the stomach. • Drugs with less half life. • Drugs absorbed readily from the GI track.
- 8. LOW DENSITY APPROACH(FDDS) IMPORTANCE • The gastric empting time in human which normally averages 2-3 hours through the major absorption zone (stomach and upper part of intestine) can result in incomplete drug release from the dug delivery system leading to reduced efficacy of administered dose. • Lower dosing and less side effects. • Beneficial in the treatment of gastric diseases.
- 9. ADVANTAGES • Enhanced bioavailability • Sustained drug delivery • Targeted therapy • Reduced fluctuation
- 10. DISADVANTAGES • The drug substances that are unstable at acidic environment of the stomach • These systems require high level of fluid in the stomach for drug delivery to float and work efficiently • Not suitable for drugs that have solubility or stability problem in GIT
- 13. • The dosage form must maintain a size larger than pyrolic spincture. • The dosage form must resist premature gastric emptying
- 14. Bio/Muco-adhesive system • Chitosan • Polyacrylic acid • Carbopol 934P, 971P, 980 • Sodium alginate • HPMC K4M,K15M,K100M • Hydroxypropylcellulose(HPC) • cholestyramine
- 15. Problems of Muco-adhesive system • Rapid removal of mucus • We are not sure weather the DF will adhere to the mucus or epithelial cell layer • DF may adhere to esophagus resulting in drug induced injuries
- 16. HIGH DENSITY APPROACH • Density should be more than stomach content i.e. 3 gm/cm3 • Prepared by coating or mixing drug with heavy inert material • Diluents- barium sulphate zinc oxide titanium dioxide iron powder
- 17. Problems with higher density approach • Higher amount of drug require • The dosage form must stand with peristaltic movement of stomach
- 23. Limitations of GRDDS • It is not recommended for drugs which are unstable at gastric/acidic PH, insoluble or very low soluble drugs and drugs which causes gastric irritation. • For floating, high level of fluid is required in GIT. Also sleeping condition is favorable for the better results of GRDDS.
- 24. • For swelling systems, it is necessary that the formulation should not exist before the appropriate swelling. • For High density system, High amount of drug is require.
- 25. THANK YOU