1. Ointments, Creams, Pastes, and Gels
Practicum in Pharmacy Technician

2. Types and Definitions
Ointments, creams, pastes, and gels have three main functions:
To protect an injured area from the environment and permit healing.
To hydrate the skin or produce an emollient effect.
To treat or medicate, either locally or systemically, by application to the skin.

3. Types and Definitions
The drug penetration and effect is dependent on several factors:
The amount of pressure and rubbing involved in applying the topical product.
The surface area where the topical product is applied.
The skin’s condition, healthy and unbroken, or injured and inflamed.
The base used in the topical product.
The use of occlusive (air tight/water tight) dressings.

4. Types and Definitions
All topical bases are classified according to two different methods:
The degree of skin penetration
The relationship of water to the base composition

5. Ointments
Ointments – semi-solid topical preparations that are applied to the skin or mucous membranes.
They are primarily made of oil.
They soften or melt a body temperature.
They spread easily.
They are non-gritty or smooth in texture.

6. Pastes
Pastes – stiff or very viscous semi-solid products that contain at least 20% solid ingredients.
They do not melt or soften at body temperature.
They are intended to be used as protectant coverings.
Example would be diaper rash cream that protects from acidic urine.

7. Creams Cream – opaque, soft solids or thick liquids for topical use.
They are primarily made of water.
The active ingredient is dissolved or suspended in water soluble or vanishing cream bases.
Creams are used externally and generally dissipate into the skin upon application.

8. Gels
Gel – semi-solid systems consisting of suspensions made up of small inorganic particles or of large organic molecules interpenetrated by a liquid.
Most gels are absorption bases that are water washable, water soluble, water absorbing, and greaseless.

9. Composition and Ingredients
Ointments, pastes, and creams can include the following components:
Active ingredient(s)
Stiffeners - enhance the viscosity
Oleaginous components – oily or greasy components
Water components
Emulsifying agents – substance that is soluble in fat and water
Humectants – substance that promotes the retention of moisture
Preservatives – for longer shelf life
Penetration enhancers –interact with both the active ingredient and the outer skin layer (stratum corneum) to increase absorption
Antioxidants – inhibits oxidation

10. Preparation and Compounding Techniques
Often, topical preparations are compounded by simply combining two or more commercial products together.
It is important to remember to combine “like” products, such as creams with creams or ointments with ointments.
Mixing a cream and ointment can lead to incompatibilities, and the two components will separate.

11. Preparation and Compounding Techniques
There are two methods used to compound topical products:
Manual – using ointment slab and spatula or a mortar and pestle to mix the ingredients.
Advantages of manual include:
It can be used to reduce the particle size of powders.
The product can be thoroughly mixed on the slab.
The slab can be easily cleaned after use.
Mechanical – using a commercial mixer or an ointment mill
Levigate – to make smooth

12. Packaging
Ointments and creams are primarily packaged in jars or tubes.
Pastes, because of their viscosity, are primarily packaged in jars.
Creams and gels can be packaged in tubes, jars, pump dispensers, topical syringes, and applicators.
All products should be in air tight containers to prevent water loss or gain.
Aluminum tubes should be used when a product has a pH of less than 6.5.

13. Labeling
The following information should be included on all compounding labels:
Generic or chemical name of active ingredient(s)
Strength and/or quantity
Assigned pharmacy lot number
Beyond use or expiration date
Storage requirements
Instructions for use.
All topical products should be labeled with an “External Use Only” auxiliary label.