Chapter 10 - Ointments, Creams, and Gels

Topical dermatological product

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

Transdermal product

designed to deliver drugs through the skin (percutaneous absorption) to the general circulation for systemic effects, with the skin not being the target organ.

Ointments

are semisolid preparations intended for external application to the skin or mucous membranes.

Ointments

may be medicated or not.

Ointments bases

may be used for their physical effects or as vehicles for medicated ointments.

- oleaginous bases

- absorption bases

- water-removable bases

- water-soluble bases

Classification of Ointment Bases

Oleaginous Bases

Also known as hydrocarbon bases

Oleaginous Bases

Emollient effects; protect against the escape of moisture

Oleaginous Bases

Effective as occlusive dressings

Oleaginous Bases

Can remain on the skin for long periods without drying out, difficult to wash off

Apis mellifera

yellow wax

yellow wax

Apis mellifera

Yellow Ointment, USP

This ointment has the following formula for the preparation of 1,000 g:

Yellow wax... 50 g

Petrolatum... 950 g

White Ointment, USP

This ointment differs from yellow ointment by substitution of white wax (bleached and purified yellow wax) and white petrolatum in the formula.

absorption bases

used as emollients

absorption bases

not easily removed from the skin with water washing, because the external phase of the emulsion is oleaginous.

absorption bases

useful as pharmaceutical adjuncts to incorporate small volumes of aqueous solutions in to hydrocarbon bases.

Hydrophilic Petrolatum, USP

has the following formula for the preparation of 1,000 g:

Cholesterol... 30 g

Stearyl alcohol... 30 g

White wax... 80 g

White petrolatum... 860 g

lanolin, USP

obtained from the wool of sheep (Ovis aries)

Ovis aries

wool of sheep

lanolin, USP

A purified waxlike substance that has been cleaned, deodorized, and decolorized.

modifies lanolin, USP

a lanolin processed to reduce the contents of free lanolin alcohols and any detergent and pesticide residues.

Water-removable bases

are oil-in-water emulsions commonly called creams.

creams.

Water-removable bases are oil-in-water emulsions commonly called _____.

water-removable bases

often called water-washable bases

water-removable bases

may be diluted with water or aqueous solutions, can absorb serous discharges

water-soluble bases

often referred to as greaseless

water-soluble bases

do not contain oleaginous components, completely water washable

water-soluble bases

large amounts of aqueous solutions are not effectively incorporated into these bases

polyethylene glycol

H(OCH2CH2)nOH

clear, colorless

<600

wax-like materials

>1000

viscosity

The greater the molecular weight, the greater the ______

PEG ointment

The general formula for preparation of 1,000 g of _________t:

PEG 3350... 400 g

PEG 400... 600 g

-incorporation

-fusion

2 general methods in the preparation of ointments

incorporation

The components are mixed until a uniform preparation is attained.

stainless steel tank

Creams and ointments in batch sizes up to 1,500 kg are manufactured in this _________, which has counter sweep agitation and a built-in homogenizer.

spatulation

When preparing an ointment by ________, the pharmacist works the ointment with a stainless steel spatula having a long, broad blade and periodically removes the accumulation of ointment on the large spatula with a smaller one.

levigation

We use this process for fine particles or powder in order to get a smooth paste by grinding the solid with water

levigation

Used to prepare the ointments and pastes, in making suspensions, pharmaceutical balms, purification of drugs, various degrees of fine

powders

Pulverization by Intervention

For incorporating a gummy material, such as camphor

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.

incorporation of liquids

Alcoholic solutions of small volume may be added easily to oleaginous vehicles or emulsion bases.

Natural balsams, e.g. Peru balsam

are usually mixed with an equal portion of castor oil before incorporation into a base.

fusion method

all or some of the components of an ointment are combined by being melted together and cooled with constant stirring until congealed.

fusion method

Components not melted are added to the congealing mixture as it is being cooled and stirred.

porcelain dish or glass beaker.

On a small scale, fusion may be conducted in

a __________

steam jacketed kettles

On a large scale, it is carried out in large ________. Once congealed, the ointment may be passed through an ointment mill (in large-scale manufacture) or rubbed with a spatula or in a mortar to ensure a uniform texture.

Ophthalmic ointments

`Sterility and metal particles content

• Microbial content

• Minimum fill

• Packaging, storage, and labeling

• Ophthalmic ointments

Compendial Requirements For Ointments

Betamethasone Valerate Ointment, USP

must meet the requirements of the tests for absence of Staphylococcus aureus and Pseudomonas aeruginosa.

microbial content

The USP states certain products should be routinely tested for microorganisms because of the way they are used.

minimum fill

The USP's minimum fill test is determination of the net weight or volume of the contents of filled containers to ensure proper contents compared with the labeled amount.

large-mouth ointment jars or in

metal or plastic tubes.

Ointments and other semisolid preparations are

packaged either in ____________ or _________

well-closed containers

Semisolid preparations must be stored in ______ to protect against contamination and in a cool place to protect against product separation in heat.

opaque or light-resistant containers.

When required, light sensitive preparations are packaged in _____________

creams

Semisolid preparations containing one or more medicinal agents dissolved or dispersed in either a water-in-oil (W/O) emulsion or an oil-in-water (O/W) emulsion or in another type of water - washable base.

creams

Topical products, Products used on mucous membranes

• Absorption

• Consistency

• Appearance

• Proportion of Oil

• Spreadability

• Stability on the skin

• Uses

• Healing power

Why do people prefer creams over ointments?

gels

sometimes called jellies

gels

semisolid systems consisting of dispersions of small or large molecules in an aqueous liquid vehicle rendered jellylike by the addition of a gelling agent

gels

ex. carbomer 934, arboxymethylcellulose or hydroxypropyl methylcellulose, tragacanth

uniformly distributed through out (Aluminum hydroxide gel)

magma

two-phase system, gel mass consisting of floccules of small distinct particles (Bentonite magma)

thixotropic.

Both gels and magmas may be _______

transdermal preparations

Addition of penetration enhancers to the topical vehicle.

paste

semisolid preparations intended for application to the skin.

paste

contain a larger proportion of solid material 25% than ointments ; stiffer

paste

can be prepared in the same manner as ointments, by direct mixing or the use of heat to soften the base prior to incorporating the solids, which have been comminuted and sieved.

paste

they remain in place after application, effectively employed to absorb serous secretions, not suited for application to hairy parts of the body

zinc oxide paste (Lassar's Plain Zinc Paste)

which is prepared by mixing 25% each of zinc oxide and starch with white petrolatum.

plasters

solid or semisolid adhesive masses spread on a backing of paper, fabric, moleskin, or plastic.

plasters

applied to the skin to provide prolonged contact at the site.

plasters

Unmedicated ______ provide protection or mechanical support at the site of application.

glycerogelatins

plastic masses containing gelatin (15%), glycerin (40%), water (35%), and an added medicinal substance (10%), such as zinc oxide

glycerogelatins

applied to the skin for the long term, melted before application, cooled to slightly above body temperature, and applied to the affected area with a fine brush

zinc gelatin

used in the treatment of varicose ulcers

glycerogelatins

also known as zinc gelatin boot because of its ability to form a pressure bandage.

glycerogelatin

Preparation:

Softening the gelatin in the water for about 10 minutes, heating on a steam bath until the gelatin is dissolved, adding the medicinal substance mixed with the glycerin, and allowing the mixture to cool with stirring until congealed.

jars, tubes, or syringes.

Topical dermatologic products are packaged in

___________

tubes or syringes.

Ophthalmic, nasal, vaginal, and rectal semisolid products are almost always packaged ______

clear or opaque glass or plastic.

Ointment jars are made of _______