Doctor, why are you prescribing an ointment?

Ever wonder why your dermatologist prescribed an eczema medication that comes in ointment form when you’d really prefer a cream? There is actually a very good reason. Each dermatologic medication is most effective in a certain form, e.g., cream, ointment, etc. The following describes the various forms that dermatological medications may take and the benefits of each form.

Cream
A cream consists of two agents, oil and water, that combine to form an emulsion of oil (50%) in water (50%). This form helps the medication contained within to penetrate the stratum corneum, the horny outer layer of the skin.

Use:

• Soothing moisturizer

Liquid
Commonly used liquids include baths, wet dressings, paints and gels that liquefy upon contact with the skin. The tar bath, which is used to treat eczema and other skin conditions, is a liquid.

Oil is a liquid that cannot be dissolved in water. Oil is often combined with other ingredients to form oil-in-water agents and water-in-oil agents.

Uses:

• Dries sweaty and/or oozing skin
• Reduces inflammation

Ointment
Ointments combine oil (80%) and water (20%). This combination generally forms a more effective barrier against moisture loss than creams and lotions so ointments tend to be better moisturizers. While moisturizing is key to controlling eczema, an ointment may not always be the form prescribed by your dermatologist because a cream or other form may more effectively deliver a prescribed medication.

Uses:

• Forms protective layer on the skin
• Strong moisturizer—better at locking in moisture than creams and lotions because contains more oil

Paste
A paste combines three agents—oil, water, and powder. By definition, a paste is an ointment in which a powder is suspended. Pastes are drying and less greasy than ointments. They make an effective carrier for some dermatologic medications. A common paste used to treat eczema contains zinc oxide (a powder), calcium hydroxide solution and oil.

Use:

• Soothes inflamed and “weeping” skin

Powder
A single agent, powder is frequently added to other agents to make shake lotions and pastes. A common powder prescribed by dermatologist is zinc oxide. Powders should never be applied to skin creases when the skin is “weeping” as clumps may form that rub and irritate the skin, making the condition worse.

Uses:

• Decreases friction on skin-to-skin surfaces
• Promotes drying of sweaty and oozing lesions

Shake Lotion
Shake lotions are made by combining powder and liquid. As the name implies, shake lotions must be shaken before being applied.

Use:

• Treat oozing lesions, wet lesions