Ointments, Creams, and Gels

Reporters: Sheila Mae BallicudAnne Valerie Villalon

Chapter 10

Ointments, Creams, and Gels

• are semisolid dosage forms intended for topical application.•may be applied to the skin, placed on the surface of the eye or used nasally, vaginally and rectally.

SEMISOLID DOSAGE FORMS

• 1.partly solid; having a rigidity and viscosity intermediate between a solid and a liquid • Dermatological preparations

intended to apply externally on the skin to produce local or systemic effect.

Topical Dermatological Product

• is designed to deliver drug into the skin in treating dermal disorder, with the skin as the target organ.

Transdermal Product• is designed to deliver drugs through the skin to the general circulation for systemic effects, with the skin not being the target organ.

Ointments• are semisolid preparations intended for external applications to the mucous membranes.•may be medicated or not.

Ointments Bases• are generally classified by the USP into 4 groups:

1.Oleaginous bases2.Absorption bases3. Water-soluble bases4.Water-removable bases

1. Oleaginous Bases•Water insoluble•Not water washable• Can't absorb water•Oily, occlusive, lack cosmetic appeal

1. Oleaginous Bases• also termed as Hydrocarbon bases

• an application to the skin, they have an:–emollient effect–occlusive dressings; and–protect against escape of moisture

Examples of Hydrocarbon bases:• Petrolatum• White

Petrolatum• Yellow

Ointment• White

Ointment

Petrolatum• is a purified mixture of

semisolid hydrocarbons obtained from petroleum

• also known as yellow petrolatum and petroleum jelly

• use as protectant in toenail fungus, genital rashes (non-STD), nosebleeds, diaper rash, and chest colds

• a commercial product is vaseline

White Petrolatum

• is a purified mixture of semisolid hydrocarbons from petroleum that has been wholly or nearly decolorized.• the same purpose as petrolatum• a.k.a. white petroleum jelly• commercial product is white vaseline

Yellow Ointment• has the following formula for the preparation of 1000g:

- Yellow Wax 50g- Petrolatum 950g

• Yellow wax is the purified wax obtained from the honeycomb of the bee Apis mellifera

• heals a wound and helps to improve damaged skin

• a.k.a. simple ointment, it has a slightly greater viscosity than plain petrolatum.

White Ointment

• differs from yellow ointment by substitution of white wax and white petrolatum in the formula. • used to treat extremely dry, scaly or callused skin

2. Absorption Bases•Water insoluble• Not water washable• Can absorb water• Anhydrous• Oily, occlusive, lack cosmetic appeal

2. Absorption Bases•may be used as emollients• not easily removed from the skin with water washing since the external phase of the emulsion is oleaginous.

2. Absorption Bases• are of two types:– those that permit

the incorporation of aqueous solutions in the formation of water-in-oil emulsions. (e.g. hydrophilic petrolatum)

– those that are water-in-oil emulsions and permit the incorporation of additional quantities of aqueous solutions (e.g. Lanolin)

Hydrophilic Petrolatum• Softening and moisturizing

dry, cracked, or irritated skin•Water-loving petrolatum• A mixture of cholesterol, stearyl alcohol, and white wax, in white petrolatum; used as an absorbent ointment base and topical skin protectant.

Lanolin• obtained from the wool of sheep • is a purified, wax-like substance that has been cleaned, deodorized and decolorized.• contains not more than 0.25% of water• used as base in ointments

3. Water-Removable Bases• oil-in-water emulsions

resembling creams in appearance• often called water-washable bases because the external phase of the emulsion is aqueous.•may be diluted with water or aqueous solution (e.g. hydrophilic ointments)

Hydrophilic Ointments• water-in-oil emulsion consisting

of methylparaben, propylparaben, sodium lauryl sulfate, propylene glycol, stearyl alcohol, white petrolatum, and purified water; used as an ointment base.

4. Water-Soluble Bases• do not contain oleaginous

components.• completely water-washable and often referred to as greaseless•mostly are used for the incorporation of solid substances• prototype example is polyethylene glycol ointment.

Polyethylene Glycol Ointment• is a polymer of ethylene oxide

and water represent by the formula H(OCH2CH2)nOH in which represents the average number of oxyethylene groups.• having an average molecular

weight below 600 is clear, colorless liquid with molecular weight above 1000 are waxlike white materials, those with molecular weights in between are semisolids.

Selection of the Appropriate Base• Desired releases rate of the

drug substance from the ointment base• Desirability of topical or

percutaneous drug absorption• Desirability of occlusion of

moisture from the skin• Stability of the drug in the

ointment base

Selection of the Appropriate Base

• Effect of the drug on the consistency or other features of the ointment base• Desire for a base easily

removed by washing with water• Characteristics of the surface to

which it is applied

Selection of the Appropriate Base

• STABILITY• PENETRABILITY• SOLVENT PROPERTY• IRRITANT• EASE OF APPLICATION AND REMOVAL

Preparation of Ointment• prepared by 2 general methods–a. incorporation–b. fusion• depending primarily on the

nature of the ingredients

Incorporation of Solids• If the components of an

ointment react with metal; hard rubber, spatulas may be used.• The ointment is prepared by

thoroughly rubbing and working the components together on the hard surface until the product is smooth and uniform.• Geometric dilution is used until

all portions of the powder and base are combined thoroughly and uniformly blended.

Incorporation of Solids

• It is often desirable to reduce the particle size of a powder or crystalline material before incorporation into the ointment, so it will not be gritty.

• This may be done by levigating or mixing the solid material in a vehicle in which it is insoluble to make a smooth dispersion.–levigating agent should be physically and chemically compatible with the drug and base•mineral oil for bases in which oils are the external phase•glycerin for bases in which water is the external phase

• The amount of levigating agent used should be about equal in volume to the solid material.• Mortar and pestle is used for levigation. This allows both reduction of particle size and the dispersion of the substance in the vehicle.• After levigation, the dispersion is incorporated into the oinment base by spatulation method or with mortar and pestle until the product is uniform.

Incorporation of Liquids

• Liquid substances or solutions of drugs are added to an ointment only after due consideration of an ointment base's capacity to accept the volume required.• Alcoholic solutions of small

volume maybe added quite well to Oleaginous vehicles or emulsion bases.

Fusion• All or some of the components

of an ointment are combined by being melted together and cooled with constant stirring until cogealed.• Medicated ointments and

ointment base containing components as beeswax, paraffin, stearyl alcohol, and high molecular weight PEG, which do not lend themselves well to mixture by incorporation, are prepared by fusion.

Compendial Requirements For Ointments

•Microbial content•Minimum fill• Packaging• Storage• Labeling

Microbial Content• Preparations with water tend to

support microbial growth• not require to be sterile• Examples are methylparaben,

propylparaben, phenols, benzoic acid, sorbic acid, and quarternary ammonium salt.

• Must be free from P.aeruginosa, S.aureus, yeast and molds

• Strict compliance to guideliness is required

Minimum Fill• Determination of the net weight

or volume of the contents of filled containers to ensure proper contents compared with the labelled amount.

Packaging, Labeling, Storing• Ointments and semisolids are to be place in large mouth ointments jars or metal and plastic tube.• To be stored in a cool place and tightly closed container to prevent contamination. (room or refrigerated temperatures)• Labels must include the type of base used.

Additional Standards• Viscosity and in vitro drug release• Diffusion cell studies to determine the drug's release profile from the semisolid product.

Creams• Semisolid dosage preparation

containing one or more medicinal agents dissolved in either a:–Water-in-oil emulsion•Cold cream

–Oil-in-water•Vanishing cream•Contains large percentage of water, stearic acid and other oleaginous components

Gels• Are semisolid system consisting

of dispersions of small or large molecules in an aqueous liquid vehicle rendered jellylike by the addition of a gelling agent.• Examples of Gelling agents:–synthetic macromolecules (carbomer 934)–cellulose derivatives (carboxymethyl cellulose)–natural gums (tragacanth)

• Sometimes called Jellies

Types of Gels• Single-Phase Gels -

macromolecules are uniformly distributes throughout a Liwuid with no apparent boundaries.• Two-Phase Gels/Magma Gels

- mass consisting of floccules of small distinct particles

To contain a drug substance, we use:• Solvents - alcohol and

propylene glycol• Antimicrobial

preservatives - methyl paraben, propyl paraben and chlorhexidinegluconate

• Stabilizers - edetate disodium

Transdermal Preparations

• Designed to deliver a drug systematically• Accomplished by penetrating

enhancers: dimethyl sulfoxide, ethanol, ethylene glycol, glycerin, PEG, urea, dimethyl acetamide, sodium lauryl sulphate, spans, tweens, terpents, etc.• Common compounded:

fluroniclechitin

Pastes• Semisolid preparation intended

for application to the skin.• Contain a larger proportion of

solid materials (such as 25%) than ointments and therefore are ointments.• Prepared in the same manner as

ointments, by desired mixing or the use of heat• Not suited for application to

hairy parts of the body.

Plasters• Solid or semisolid adhesive masses spread upon a backing material of paper, fabric, moleskin or plastic.• Applied to the skin to provide prolonged contact at the site.

Glycerogelatins• are plastic masses containing gelatin

(15%), glycerin (40%), water (35%) and an added medicina substance (10%) ZnO

• They are prepared by:–softening the gelatin in the water for about 10 minutes, heating on a steam bath until gelatin is dissolved–Adding the medicinal substance mixed with the glycerin–Allowing the mixture to cool with stirring until congealed

• Applied to the skin for long-term residence

Packaging Semisolid Preparation• Topical Dermatological

Product– are packaged in either jars, tubes, or syringes whereas opthalmic, nasal, vaginal and rectal semisolid products are almost always packaged in tubes or syringes.

Filling Ointment Jars• Are filled on small scale in the pharmacy by carefully transferring the weighed amount of ointment into the jar with a spatula.

Filling Ointment Tubes

• Are filled from the open back end of the tube, opposite from the cap end.• Can also be filled using a

“Caulking gun” system where the semisolid is filled into the chamber and the product is delivered into the tube.

Filling Syringes• Can be filled either by drawing the semisolid into the barrel using the plunger, or by removing the plunger and filling through the back end of the syringe.

Features and Use of Rectal Preparation• used for topical application to

the perianal area and for insertion within the anal canal.• used to treat local conditions–anorectal pruritus–inflammation; and–pain and discomfort associated with hemorrhoids

Features and Use of Vaginal Preparation• vaginal surface is lined with

squamous epithelium produced by various underlying glands• used to treat vulvovaginal

infections–vaginitis–conditions of endometrial atrophy–contraception with spermatocidal agents

Drug Release from Semisolid Dosage Form• Semisolid dosage forms - to deliver a drug to the surface of the skin or to be absorbed into the surface of the skin.

Doomo Arigatoo!

Sayoonara!