Osmotic activated Drug Delivery System Seminar(DDS).pptx

It gives detailed information about the Osmatic drug delivery system

1. INSTITUTE OF PHARMACY AND RESEARCH, BADNERA Osmotic Activated Drug Delivery System Presented by- Ms. Pranjal S. Deshmukh M.Pharm I Year (Pharmaceutics) Guided by- Ms. Vaishnavi R. Belokar Assistant Professor Dept. of Pharmaceutics 1

2. CONTENTS : Introduction Basic Components of Osmotic System Types of Osmotic System Marketed Products Advantages Disadvantages References 2

3. Introduction : Osmotic activated drug delivery system uses the osmotic pressure for controlled delivery of drugs by using osmogens . Osmosis: It is the movement of solvent from a region of lower solute concentration to a region of higher solute concentration through a semi-permeable membrane. Osmotic pressure: The pressure exerted by the flow of water through a semi- permeable membrane separating the two solutions with different concentrations of solutes. 3

4. Osmotic drug delivery has come a long way since Australian Physiologists Rose and Nelson developed an implantable pump in 1955. These system can be used for both routes of administration i.e. oral and parenteral. In osmotic activated drug delivery systems, drug reservoir can be either solution or solid formulation contained within semi permeable housing with controlled water permeability. The drug is activated to release in solution form at a constant rate through a special delivery orifice. The rate of drug release is modulated by controlling the gradient of osmotic pressure. 4

5. Basic Components of Osmotic System : Osmotic pumps essentially contains a drug and semipermeable membrane. In this case, drug itself may act as an osmogen and shows good aqueous solubility(e.g. potassium chloride pumps). If the drug does not possess any osmogenic property, the osmogenic salts and other sugars can be incorporated in the formulation. Osmogens are freely water soluble and capable of producing osmotic pressure. Single osmogens can be used for the formulations and in some case combination of osmogens have been used. Apart from these essential components, other materials such as hydrophilic and hydrophobic polymers, hydrogels, wicking agents, solubilizing agents, surfactants, flux regulating agents, pore forming agents, lubricants, binders, gliadants , diluents, etc have been used depending on the type of formulations. 5

6. Drug: Itself may act as an osmogen otherwise osmogenic salts can be added in the formulation. Semipermeable membrane: Should have sufficient water permeability ; should be sufficient to withstand the pressure within the device. Hydrophilic and hydrophobic polymers: CMC, HPMC, ethyl cellulose. Wicking agents: SLS, PVP, bentonite. Solubilizing agents: PVP, PEG. Osmogens : NaCl, KCl . Surfactants: Poly oxyethylenated castor oil, poly oxyethylenated glyceryl recinoleate . Coating agents: Acetone-methanol(80:20), acetone-water(90:10). Flux regulator: Polypropylene, polybutylene. Pore forming agents: Calcium nitrate, potassium sulphate. 6

7. Types of Osmotic System: Osmotic activated drug delivery system 7 Implantable Pumps Oral Pumps Rose Nelson Osmotic Pump Higuchi Leeper Osmotic Pump Higuchi Theeuwes Osmotic Pump Elementary Osmotic Pump Sandwiched Osmotic Tablets

8. Implantable Pumps: Rose Nelson Pump : The present day osmotic devices are modified versions of Rose Nelson pump, which was introduced by two Australian Physiologists Rose and Nelson in 1955, who were interested in the delivery of drugs to the sheep and cattle gut. A semi-permeable wall and water chamber surround an elastic diaphragm consisting of a section of excess salt. These two chambers are separated by a semi-permeable barrier. This creates a difference in gradient and osmotic pressure; thus, the water tends to move towards the chamber of salt from its chamber. As water enters the salt chamber, the volume of the salt chamber increases; hence, the diaphragm starts to distend, resulting in the pumping of the drug. The drug is then pumped out of the device. 8

9. Fig. Rose Nelson Osmotic Pump 9

10. Higuchi Leeper Osmotic Pump : In the 1970s, Alza Corporation introduced the Higuchi–Leeper pump, a simplified form of the Rose–Nelson pump. The water chamber is absent in the Higuchi–Leeper pump. Instead, the water required for device activation is drawn from the environment in the device’s surroundings. This is a beneficial modification, as it enables the storage of prepared and drug-loaded pumps for a month. Fig. Higuchi Leeper Pump 10

11. Higuchi Theeuwes Osmotic Pump : In the 1970s, Higuchi and Theeuwes introduced a pump that had an outer casing made up of a rigid semi-permeable membrane. The drug is loaded in the device only prior to its use, which extends advantage for storage of the device for longer duration. The rate of drug release from the device when it is operated depends on the outer membrane’s permeation ability, and a time course that the salt has set is followed. Fig. Higuchi Theeuwes Osmotic Pump 11

12. Oral Pumps : Elementary osmotic pump was invented by Theeuwes in 1974. It is fabricated as a tablet coated with semipermeable cellulose acetate membrane. A small orifice of about 0.5-1.5 mm is drilled through the membrane coating. When the device is put into operation, water enters through a semi-permeable wall by imbibition into the core, creating osmotic pressure and eventually drug solution comes out through a small orifice. Fig. Elementary Osmotic Pump 12 Elementary Osmotic Pump :

13. Sandwiched Osmotic Tablets : It is with two delivery orifices each for two drug layers and between these layers polymeric push layer is sandwiched. When placed is aqueous environment, the middle push layer containing the swelling agent swells and the drug is released from the two orifices situated on opposite sides of the tablet. 13 Fig. Sandwiched Osmotic Tablets

14. Marketed Products: 1. Products Incorporating ALZA’s OROS® Technology- Cardura® XL (doxazosin mesylate) sold in Germany for the treatment of hypertension. Covera -HS® (verapamil) a controlled release system for the management of hypertension and angina pectoris. Sudafed® (pseudoephedrine) for 24-hour relief of cold and other respiratory allergies. Procardia XL® (nifedipine) extended release tablet for the treatment of angina and hypertension. 2. Product Incorporating ALZA's DUROS® Implant Technology- Viadur ® (leuprolide acetate implant) is indicated in the palliative treatment of advanced prostate cancer, it delivers leuprolide continuously for 12 months. 14

15. Advantages: Osmotic activated drug delivery system gives zero order release profile (which is most desirable). Drug release is independent of gastric pH, GI motility and hydrodynamic conditions. This system offers improved bioavailability. It reduces dosing frequency and improves patient compliance. Ease of administration and greater effectiveness in the treatment of chronic conditions. 15

16. Disadvantages: Chance of toxicity due to dose dumping. Expensive. Release of drug depends on : -Size of hole/aperture -Surface area -Thickness and composition of membrane. 16

17. References: S.P.Vyas & R.K.Khar , Controlled Drug Delivery-Concepts and Advances, Vallabh Prakashan , Second Edition (2012), 454-478. P.P.Patil , B.P.Gayakwad , et.al., A Textbook of Drug Delivery Systems, P.V. Publication (2021), 112-119. Yosif Almoshari , Osmotic Pump Drug Delivery Systems-A Comprehensive Review, Pharmaceuticals (2022), 1430(15), 1-16. www.google.com 17

18. THANK YOU! 18