Upload
cristina-joy-reyes
View
557
Download
2
Embed Size (px)
Citation preview
Presented By:
Reyes, Cristina Joy F.
- are semisolid dosage forms intended fortopical application. They may be applied to theskin, placed on the surface of the eye, or usednasally, vaginally, or rectally.
Ointment
- are semisolid preparations intended forexternal application to the skin or mucousmembranes.
1. UNMEDICATED OINTMENTSThese ointments do not contain any drugs. They are useful as emollients, protectants or lubricants.Example: Petroleum jelly.2. MEDICATED OINTMENTSThese ointments contain drugs which show local or systemic effects. a) Dermatologic ointmentsb) Ophthalmic ointmentsc) Rectal ointmentsd) Vaginal ointmentse) Nasal ointments
- used for their physical effects or as vehicles for medicated ointments.
Four groups:
1. Oleaginous bases
2. Absorption bases
3. Water-removable bases
4. Water-soluble bases
Ointment Bases
Oleaginous Bases (Hydrocarbon Bases)
• have an emollient effect
• protect against the escape of moisture
• are effective as occlusive dressings
• can remain on the skin for long periods without drying out
• difficult to wash off
Examples: Petrolatum, white petrolatum, white ointment, and yellow ointment
Absorption Bases
• used as emollients
• not easily removed from the skin with water
washing
• incorporation of aqueous solution.
Examples:
Hydrophilic Petrolatum
Lanolin
Water-Removable Bases
- are oil-in-water emulsions commonly calledcreams
• external phase of the emulsion is aqueous
• easily washed from skin
• diluted with water or aqueous solutions.
• can absorb serous discharges
Example: Hydrophilic Ointment
Water-Soluble Bases
• do not contain oleaginous components.
• are completely water washable and often referred to as greaseless.
• they soften greatly with the addition of water
• incorporation of aqueous solutions are not effectively
• used for incorporation of solid substances.
Example:
Polyethylene Glycol Ointment
CLASSIFICATION OF OINTMENT BASES
Preparation of Ointment
1. INCORPORATION METHOD – involves the blending ofan ingredient into the vehicle. This is done using aglass slab and a pair of spatulas for small volumes orusing a mortar and pestle for larger volumes.
2. FUSION METHOD - used to incorporate ingredientswith solid, hard properties such as waxes. All or someof the components of an ointment are combined bybeing melted together and cooled with constantstirring until congealed.
- are semisolid preparations containing one ormore medicinal agents dissolved or dispersed ineither a water-in-oil (W/O) emulsion or an oil-inwater (O/W) emulsion or in another type ofwater-washable base.
Example of a W/O cream: Cold cream
Example of an O/W cream: Vanishing cream
Creams
Preparation of cream involves separating the formula components into two portions:
Lipid and Aqueous.
1. Lipid portion contains all water-insoluble components.
2. Aqueous portion contains all the water-soluble components.
Preparation of Creams
- are semisolid systems consisting of dispersions
of small or large molecules in an aqueous liquidvehicle rendered jellylike by the addition of agelling agent.
Gelling agents are used syntheticmacromolecules
Gels (Jellies)
-
1. SINGLE – PHASE GELS are gels in which themacromolecules are uniformly distributedthroughout a liquid with no apparent boundariesbetween the dispersed macromolecules and theliquid.2. TW0 – PHASE GELS (magma “Milk magnesia”)consisting of floccules of small distinct particles
Classification Of Gels
• formed by dispersing the molecule in thecontinuous phase (e.g., by heating starch)
• by cross-linking the dispersed molecules
• by changing the pH (as for carbomers)
• by reducing the continuous phase (as for jelliesformed with sucrose).
Preparation of Gels
Definition
• Cream – Emulsion of oil and water inapproximately equal proportions.
• Ointment – Combines oil (80%) andwater (20%).
• Gel – Liquefies upon contact with theskin.
- semisolid preparations intended for application to the skin. They generally contain a larger proportion of solid material (such as 25%) than ointments and therefore are stiffer.
Example: Zinc oxide paste (Lassar's Plain Zinc Paste)
Pastes
Pastes
- are solid or semisolid adhesive masses spread on a backing of paper, fabric, moleskin, or plastic.
Example: Salicylic Acid Plaster
Plasters
- are plastic masses containing gelatin (15%),glycerin (40%), water (35%), and an addedmedicinal substance (10%), such as zinc oxide.
Glycerogelatins
Thank You For Listening
Any Questions?
Or any Clarification?
ALLEN, L. V., POPOVICH, N. G., ANSEL, H. C., & ANSEL, H. C. (2005). Ansel's pharmaceutical dosage forms and drug delivery systems. Philadelphia, Lippincott Williams & Wilkins.
REFERENCE: