1. Controlled Release Oral Drug Delivery Systems Pankaj Shukla M. Pharm 1st year Dept. of Pharmaceutics KLE University’sCollege of Pharmacy Belgaum

3. Hydrodynamically balanced drug delivery system

4. pH- activated drug delivery system

5. Ion exchange resinates as control drug delivery system

10. Semipermiable membrane

11. Hydrophilic and hydrophobic polymers

12. Wicking agents

13. Solubilizing agents

14. Surfactants

15. Coating solvents

16. Plasticizers

17. Flux regulators

19. Elementary osmotic pump

20. Push-pull osmotic pump

21. Controlled porosity osmotic pumps

22. Osmotic bursting osmotic pumps

23. Combination of effervescent agents with the drug

24. Pump for insoluble drugs

31. The inner is microporous membrane, which is made up of cellulosic material containing some pore forming agents, covered by a semipermeable membrane.

37. Delivery rate is independent of pH and outside agitation.

38. Delivery of drug takes place in solution form which is ready for absorption.

40. Residence time of the system in body varies with the gastric motility and food intake.

41. It may cause irritation or ulcer due to release of saturated solution of drug.

43. HYDRODYNAMICALLY BALANCED DRUG DELIVERY SYSTEM

46. Am = Effective surface area ,

54. The gel barrier controls the rate of solvent penetration into the device & the rate of drug release from the device.

56. Minimizing the mucosal irritation due to drugs, by drug releasing slowly at controlled rate

57. Site specific drug delivery.

58. Treatment of gastro intestinal disorders such as gastro-esophageal reflux.

59. Simple and conventional equipments required for manufacture.

61. Not suitable for drugs with stability or solubility problems in stomach.

63. pH- Activated Drug Delivery System

65. Drugs administered orally would encounter a spectrum of pH ranging from 7 in the mouth, 1 - 4 in the stomach and 5 - 7 in the intestine.

69. This leaves a microporous membrane of intestinal fluid insoluble polymer of Ethylcellulose, which controls the release of drug from the core tablet.

71. Marketed products

72. ION EXCHANGE RESINATES AS CONTROL DRUG DELIVERY SYSTEM

73. Principle A Cation exchange resin generally has Sulphonic and Carboxylic functional groups as an integral part of the resin and an equivalent amount of cationic drug molecules. An Anion exchange resin generally has quaternary ammonium groups and polyalkylamine functional groups as an integral part of the resin and an equivalent amount of anionic drug molecules.

75. Types of ion-exchange resins

77. Biological half life should be between 2-6 hrs, drugs with t1/2 < 1 hr or > 8 hrs are difficult to formulate.

78. The drug is to be absorbed from all regions of GI tract.

80. Porosity

81. Swelling

83. General preparation of drug resinates Column process: A highly concentrated drug solution is eluted through a bed or column of the resin until equilibrium is established. Batch process: The resin particles are stirred with a large volume of concentrated drug solution.

85. Reduced fluctuations in blood and tissue concentration level can be achieved.

86. Protection of drug from gastric enzymes.

90. Yie w.chein, Novel Drug Delivery System, edition 2, vol-3,pg no.30 – 32