Transcript creams
CREAMS MS.WAJIHA IFFAT OBJECTIVES: After the end of this topic, the student will be able to : •Define creams •Classify creams •Method of preparation •prepare a cream from first principles • incorporate solids and liquids into a cream base Creams BP DEFINES : “Creams are formulated to provide preparation that are essentially miscible with skin secretion. they are intended to be applied to the skin or certain mucous membranes for protective ,therapeutic, or prophylactic purposes especially when occlusive effect is not necessary.” Creams In USPXVIII ,creams are defined as “ semisolid emulsions of either oil in water or water in oil type.” “ semisolid emulsions usually medicated ,intended for external application.” Creams Aqueous cream: aqueous cream , cetrimide cream, cetomacrogol cream Oily cream: oily cream /hydrous ointment Cosmetic creams: All purpose cream, baby cream, barrier cream, bleaching cream, cleansing cream cold cream, hair cream, hand cream, vanishing cream. Medicated creams: Creams Creams are reserved for external preparation. A cream may be water in oil or oil in water depending on the emulsifying agent used. They are soft ,easy to apply ,cooling to skin ,easily water-removable. w/o cream: oily creams Contains: emulsifying agents of natural origins( bees wax, wool alcohols, wool fat properties :Emollient. Creamy, white or translucent and stiff. Creams o/w creams: aqueous creams Contains: synthetic waxes e.g., cetomacrogols & macrogols Properties: Causes rapid absorption & penetration Thin ,white & smooth consistency Creams METHOD OF PREPARATION: TRITURATION: Used for finely divided insoluble powder particles or liquids insoluble powder are added by geometric dilution Liquids are added by making well in centre. Air pocket formation avoided. Involved the use of glass slab when small quantities are used Mortar and pestle used when we have large quantities. Creams LEVIGATION: Incorporation of insoluble coarse particles. Also known as “Wet grinding”. insoluble coarse powder is rubbed with molten base or liquid or a semi solid base. A considerable shearing force is applied to avoid grittiness. Creams Hygiene: ( aseptic condition) All equipment & spatula to be cleaned by IMS. (70% ethanol should be used) Determine the miscibility of the substances being incorporated. Melt the fatty base .substances with the highest melting point to be melt first. These bases then cooled to 60°C. Temperature of the aqueous phase to be adjusted to 60°C. The disperse phase to be incorporated to the continuous phase at the same temperature. Avoid air pockets & hasty cooling. Creams Incorporation Of solid Ingredients Into Cream Base: Solid particles can be incorporated after the bases cools Soluble solids: added to the molten cream at the lowest possible temperature& the mixture stirred until cold. Insoluble solids: incorporated by using tile & spatula or mortar and pestle using doubling technique. Creams Coarse powder: minimum quantity of cream should be placed in the centre of the tile & used to levigate the powders. Fine powders : may be triturated to into other wise finished creams on ointment tile. (geometric dilutions. Creams Incorporation Of Liquids: Non volatile ,miscible liquids: may be mixed with molten cream in evaporating basin. if a preprepared base is used then follow procedure for volatile or immiscible liquids. Volatile or immiscible liquids: E.gs coal tar should be triturated with creams on tile .a very small amount of creams should be placed on tile and a well made in centre. small quantities are folded gently to avoid splashing. Creams Diluted creams: If the diluents is stated in the manufacturer data sheet Freshly prepared No heating should be involved. Should be carried out in aseptic conditions. Should not be used more than 2 wks. REFERENCES Compounding and Dispensing by Christopher A Langley & Dawn Belcher pg. 65-91. Compounding and Dispensing by john F. Marriot, Keith A. Wilson Christopher A Langley & Dawn Belcher pg.147-151 Pharmaceutical Practice by D M Collett pg:116-117 Sprowls’ American Pharmacy pg:273-274 Pharmaceutics practice by Winfield. Creams THANK YOU!! ANY QUESTION??? ASSIGNMENT : MAKE A LIST OF MEDICATED CREAM WITH THEIR BRAND NAME.