7. Introduction to different dosage form part 7.ppt
- 1. INTRODUCTION TO DIFFERENT DOSAGE FORMS Presented by Mr. Parimal Hadge Datta Meghe Institute of Medicinal Science(DU) Salod(H);Sawangi(M); Wardha:
- 2. Learning objectives: The learner will be able to learn: • Different types of dosage form • Needs of dosage form • Detail account on Suspension dosage form
- 3. Biphasic liquid dosage forms The liquid which consist of two phases are known as a biphasic liquid dosage forms. They are sub categorized into two different forms namely as – I) Emulsion II) Suspension In emulsion both phases are available in liquid where as in suspension, finely divided solid particles are suspended in liquid medium.
- 4. Suspension Suspensions are the biphasic liquid dosage forms of medicament in which finely divided solid particles ranging from 0.5 to 5 micron are dispersed in a liquid or semisolid vehicle, with aid of single or combination of suspending agent. In which solid particles acts as disperse phase where as liquid vehicle acts as continuous phase The external phase (suspending medium) is generally aqueous in some instance, may be an organic or oily liquid for non oral use. The particle size for non oral suspension is so important to avoid grittiness to skin.
- 5. Advantage of suspension Suspension can improve chemical stability of certain drug. E.g. Procaine penicillin Drug in suspension exhibits higher rate of bioavailability than other dosage forms. Solution > Suspension > Capsule > Compressed Tablet > Coated tablet Duration and onset of action can be controlled. E.g. Protamine Zinc- Insulin suspension. Suspension can mask the unpleasant/ bitter taste of drug. E.g. Chloramphenicol
- 6. Disadvantage of suspension Physical stability , sedimentation and compaction can causes problems. It is difficult to formulate. Uniform and accurate dose can not be achieved unless suspension are packed in unit dosage form. All suspensions are required to be shaken before measuring of dose. The storage of suspension may lead to changes in disperse system especially, when there is fluctuations in temperatures.
- 7. Ideal qualities of good suspension It should settle slowly & easily re – dispersed on shaking It should readily & evenly pour from container. It should be chemically inert. It should not forms hard cake. It should prevent degradation of drug or to improve stability of drug. It should mask the taste of bitter of unpleasant drug.
- 8. Flocculated suspension In this type, solid particles are loosely aggregates themselves, means individual particles are come in contact with each other to forms network like structure called as a floccules. These flocs are light, fluffy in nature, which are held together by weak van der waals force of attraction. Aggregation is achieved by adding flocculating agent. This suspension will readily sediments. This suspension posses better physical stability but less bioavailability as compared to deflocculated suspension due to dissolution of floccules.
- 9. Deflocculated suspension In this type of suspension, individual particle exits as a separate entity, means particles carry a finite charges on their surface . Hence particles approaches each other, they experience repulsive forces. This force create a high potential barrier, which prevents a aggregation of particles. During storage, these suspension shows a sedimentation at slow rate, due to that particles forms a close packing arrangement. So that it is difficult to re dispersed on agitation & forms a cake or claying which is hard in nature. This type of suspension have shorter shelf life but high bioavailability as compared to flocculated suspension.
- 10. Difference between flocculated & deflocculated suspension Flocculated Suspension Deflocculated suspension Particles form loose aggregates & forms network like structure. Particle exist as separate entities. Particles experience attractive forces. Particles experience repulsive forces. Supernatant liquid is clear. Supernatant liquid is cloudy. The rate of sediment is high. The rate of sediment is slow. Sediment is rapidly formed. Sediment is slowly formed. sediment are loosely packed, hence hard cake is not formed. Sediments are closely packed, hence hard cake is formed. The sediment is easy to redisperse on shaking. Sediment is difficult to redisperse on shaking. (due to formation of hard cake) Bioavailability is comparatively less. Bioavailability is relatively high. The suspension is not pleasing in appearance. The suspension is pleasing in appearance.
- 11. References: • R. M. Mehta text book for pharmaceutics I • Lachman, A reference book for pharmaceutics • Martin, A reference book for pharmaceutics
- 12. Thank you