OINTMENTS, CREAMS, AND GELS (PART 1)

Ointments
Creams
Gels

Types of semi-solid dosage forms intended for topical application.

Skin
Eye
Nasally
Vaginally
Rectally

Where can semi-solid dosage forms can be applied?

Local
Systematic

Topical applications can be designed for either (effects)?

Topical

Dermatological product is designed to deliver drugs into the skin in treating dermal disorders, with the skin as the target organ.

Transdermal

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

Salve

Another Term for Ointments

Medicated Ointment
Non-Medicated Ointment

THERE ARE TWO TYPES OF OINTMENTS:

Medicated Ointments

THERE ARE TWO TYPES OF OINTMENTS:
Contains therapeutic agents.

Non-Medicated Ointments

THERE ARE TWO TYPES OF OINTMENTS:
Also referred to as ointment bases and used as an emollient and for their lubricating effect or vehicle in the preparation of medicated ointment.

Oleaginous
Absorption
Water-Removable
Water Soluble

Types of Bases for Ointments

Hydrocarbon Bases

Oleaginous Bases are also termed?

Oleaginous Bases

Types of Bases for Ointments
- On application to the skin, they have an emollient effect, are effective as occlusive dressing, protect against the escape of moisture, can remain on the skin for long periods without drying out, and because of their immiscibility with water are difficult to wash off.
- Water and aqueous preparation may be incorporated, but only in small amounts and with some difficulty.

Petrolatum
White Petrolatum
Yellow Ointment
White Ointment

Common Examples of Hydrocarbon Bases

Yellow Petrolatum
Petrolatum Jelly

Petrolatum, USP is also known as?

Petrolatum, USP

Common Examples of Hydrocarbon Bases
- A purified mixture of semi-solid hydrocarbons obtained from petroleum.
- It is an unctuous (greasy or oily) mass, varying in color from yellowish to light amber.
- It melts at 38C to 60C and may be used alone or in combination with other agents as an ointment base

More Viscous

For Petrolatum, when added of more waxes, what is the texture?

Soft

For Petrolatum, when it is only petrolatum, what is the texture?

High Pressure

Petrolatum, USP
Can be melted easily and degrade once exposed to?

Petroleum Jelly
White Soft Paraffin

White Petrolatum, USP is also known as?

White Petrolatum, USP

Common Examples of Hydrocarbon Bases
- A purified mixture of semi-solid hydrocarbons from petrolatum that has been wholly or nearly decolorized.
- Skin Protectant (Skin Irritations, Wounds, Abrasions or Burns) from dusts.

Simple Ointment

Yellow Ointment, USP is also known as?

Yellow Ointment, USP

Common Examples of Hydrocarbon Bases
- Each 100g of this ointment contains 5g of yellow wax and 95g of petrolatum
- Slightly greater viscosity than plain petrolatum.

White Ointment, USP

Common Examples of Hydrocarbon Bases
This ointment differs from yellow ointment by substitution of white wax (bleached and purified yellow wax) and white petrolatum in the formula

Absorption Bases

Types of Bases for Ointments
- These bases may be used as emollients, although they don’t provide the degree of occlusion afforded by oleaginous bases. - Are not easily removed from the skin with water washing, because the external phase of the emulsion is oleaginous.

a. Those that permits the incorporation of aqueous solutions resulting in the formation of water in oil (W/O) emulsions.
b. Those that are W/O or emulsion bases that permit the incorporation of additional quantities of aqueous solution.

Absorption bases are of two types:

Hydrophilic Petrolatum
Anhydrous Lanolin, USP
Lanolin
Cold Creams

COMMON EXAMPLES OF ABSORPTION BASES:

Cholesterol (3g)
Stearyl Alcohol (3g)
White Wax (8g)
White Petrolatum (86g)

Composition of Hydrophilic Petrolatum
It can absorb water with formation of water-in oil emulsion.

Refined Wool Fat

Anhydrous Lanolin, USP is also known as?

Anhydrous Lanolin, USP

COMMON EXAMPLES OF ABSORPTION BASES:
It is obtained from the wool of sheep (ovis aries); a purified wax like substance that has been cleaned, decolorized, and contains not more than 0.25% water

Lanolin

COMMON EXAMPLES OF ABSORPTION BASES:
 A semi-solid, fat-like substance obtained from the wool of sheep. It is a water-in-oil emulsion that contains 25% to 30% water.

Cold Creams

COMMON EXAMPLES OF ABSORPTION BASES:
Is a semi-solid, white, water-in-oil emulsion prepared with cetyl ester wax, white wax, mineral oil, sodium borate, and purified water. This is employed as an emollient and ointment base.

Galen Scerate

Cold Creams originated from?

Water- Removable Bases

Types of Bases for Ointments
- These are oil-in-water emulsions that are capable of being washed from the skin or clothing with water.
- For this reason, they are known as water washable ointment bases.
- They have the ability to absorb serous discharges in dermatological conditions.

Hydrophilic Ointment, USP

COMMON EXAMPLE OF WATER-REMOVABLE BASES:

Methylparaben
Propylparaben
Sodium Lauryl Sulfate
Propylene Glycol
Stearyl Alcohol
White Petrolatum
Purified Water

Hydrophilic Ointment Ingredients

Methylparaben
Propylparaben

Hydrophilic Ointment Ingredients
Serves as the Preservative

Sodium Lauryl Sulfate

Hydrophilic Ointment Ingredients
Serves as the Surfactant/ Emulsifier

Propylene Glycol

Hydrophilic Ointment Ingredients
Serves as an Humectant (to prevent the formulation to dry out)

Water Soluble Bases

Types of Bases for Ointments
- Do not contain oleaginous components.
- They are completely washable by water and often referred to greaseless.
- Because they soften greatly with the addition of water, large amounts of aqueous solutions are not effectively incorporated into these

Polyethylene Glycol (PEG) Ointment, NF

COMMON EXAMPLE OF WATER-SOLUBLE BASES:
Combining 40g of PEG3350, a solid, with 60 grams of PEG400, a liquid results in a pliable semi-solid ointment

Molecular Weight

The number beside PEG (like PEG3350) corresponds to?

Solid

In Polyethylene Glycol
High Molecular Weight is?

Liquid

In Polyethylene Glycol
Low Molecular Weight is?

Semi-Solid

In Polyethylene Glycol
In Between Molecular Weight is?

- Desired release 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
- Effect, if any 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 preparation of ointments

Selecting of the base to use in the formulation of an ointment depends on careful assessment of a number of factors, including the following:

Incorporation
Fusion

Preparation of Ointments

Incorporation

Preparation of Ointments
- Small Scale
- The components of the ointment are mixed together by various means until a uniform preparation has been attained

Mechanical Ointment Roller Mills

Preparation of Ointments
In large scale incorporation, this machine coarsely formed ointments through moving stainless-steel rollers resulting in a smooth uniform product.

Fusion

Preparation of Ointments
- Involves melting of some components, mixing, then cooled with constant stirring until congealed; for anhydrous ointments
- Used for anhydrous types of preparation (prevent evaporation of aqueous solutions)

Large Steam Jacketed Kettles (Large)
Beaker on Water Bath (Small)

Equipment used for Fusion

Chemical Antimicrobial Preservatives

PRESERVATION OF OINTMENTS
By the addition of? (inhibit the growth of contaminating microorganisms)

Parabens
Benzoic Acid
Sorbic Acid
Quaternary Ammonium Salts (Benzal Ammonium Chloride)

Examples of Chemical Antimicrobial Preservatives