ointment, cream, gel , pastes, plasters, glycerogelatin

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.

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