Controlled release medication .pptx

Controlled release medication

1. Dr. Neha Srivastava Controlled Drug Delivery System

2. Factors Biopharmaceutical Classification Drug in dosage form Drug at absorption site Drug in body Release Absorption Rate limiting step in CR Rate limiting step in IR

3. Drug release pattern

4. Drug release pattern Zero order and first order release

5. Advantages Total dose is low. Reduced GI side effects. Reduced dosing frequency. Better patient acceptance and compliance. Less fluctuation at plasma drug levels. More uniform drug effect Improved efficacy/safety ratio. 5

6. Disadvantages ■ Dose dumping. ■ Reduced potential for accurate dose adjustment. ■ Need of additional patient education. ■ Stability problem. 6

7. Factors Biopharmaceutical Classification Molecular weight Aqueous Solubility Partition coefficient Drug pKa and Ionization Drug permeability Drug Stability Mechanism and site of absorption

8. Factors Route of administration Oral route Parentral route Transdermal route

9. Factors Pharmacokinetics parameters Absorption rate Elimination half life Rate of metabolism Dosage form Index

10. Factors Pharmacodynamic parameters Drug dose Therapeutic range Therapeutic index Plasma concentration response

11. Factors Pharmacodynamic parameters Drug dose Therapeutic range Therapeutic index Plasma concentration response

12. Oral controlled release system Conventional and ease Greater flexibility Ease of production Continuous release system Pulsatile release system

13. Dissolution : 1.Matrix Encapsulation Diffusion : 1. Matrix Reservoir Combination of both dissolution & diffusion. Osmotic pressure controlled system Mechanism of controlled release

14. Oral controlled release system Dissolution controlled release system 14 ■ Solid substances solubilizes in a given solvent. ■ Mass transfer from solid to liquid. ■ Rate determining step: Diffusion from solid to liquid. ■

15. Dissolution controlled System Matrix system Reservoir System 15

16. Dissolution controlled System Matrix system Reservoir System 16

17. Diffusion-controlled release system 17 Major process for absorption. No energy required. Drug molecules diffuse from a region of higher concentration to lower concentration until equilibrium is attainded. Directly proportional to the concentration gradient across the membrane.

18. Dissolution controlled System Matrix system Reservoir System 18

19. Dissolution controlled System Matrix system 19 Rigid Matrix Diffusion Materials used are insoluble plastics such as PVP & fatty acids. Swellable Matrix Diffusion Also called as Glassy hydrogels.Popular for sustaining the release of highly water soluble drugs. Materials used are hydrophilic gums. Examples : Natural- Guar gum,Tragacanth . Semisynthetic - HPMC,CMC, Xanthum gum. Synthetic -Polyacrilamides. Examples: Glucotrol XL, Procardia XL

20. Reservoir System Rate controlling steps : Polymeric content in coating, thickness of coating, hardness of microcapsule. 20

21. Dissolution & Diffusion Controlled Release system ■ Drug encased in a partially soluble membrane. ■ Pores are created due to dissolution of parts of membrane. ■ It permits entry of aqueous medium into core & drug dissolution. ■ Diffusion of dissolved drug out of system. ■ Ex- Ethyl cellulose & PVP mixture dissolves in water & create pores of insoluble ethyl cellulose membrane. Insoluble membrane Pore created by dissolution of soluble fraction of membrane Entry of dissolution fluid Drug diffusion 21

22. Osmotic Pressure Controlled Drug Delivery System 22 ■ Definition ■ Procedure ■ Diagram ■ Modifications

23. Osmotic Pressure Controlled Drug Delivery System 23 ■ ■ ■ ■ https://youtu.be/QOOQ5pOZyWU

24. Ion Exchange resins 24 ■ ■ ■ ■

25. 25 ■ ■ Thank You….