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International Journal of Pharmaceutical Compounding

Vol. 7 No. 6 November/December 2003

4

Are these drugs, cosmetics or cosmeceuticals? Dry skin iscurrently considered a problem within the cosmetics category,so compounding preparations for dry skin would be in the cat-egory of cosmetics compounding. This is in line with the his-torical aspects of cosmetics, which were formerly prepared by

the apothecary.

Composition of Dry-Skin PreparationsDry-skin preparations may contain emollients, hygroscopic

agents, keratin softening agents and antipruritics. Many of themore common agents are listed in Table 1. Emollientshelp to maintain the soft, smooth and pliable

appearance of the skin. They function by their ability to re-main on the skin surface, or stratum corneum; to act as alubricant; to reduce flaking; and to improve the skins ap-pearance. Another term ascribed to some of these emol-lients is refatting additivesor refatteners. These substancesimprove the lipid content of the upper layers of the skin andprevent defatting or drying out of the skin. These are gen-

erally lipophilic substances and are generally occlusive innature. They remain on the skin surface and reduce thetransepidermal water loss by minimizing evaporation. Ex-amples include the oil-based ingredients such as mineral oil,petrolatum, lanolin, vegetable oils and white ointment, hy-drophilic petrolatum and others.

Hygroscopic agents, humectants or hydrating substancesused to retard moisture loss from a product during use andto increase moisture content of the material in contact withthe skin. Examples of humectants include glycerin, propy-lene glycol and sorbitol.

Keratin softening agentsprovide for an increased water-holding capacity of the skin. The classic agent is urea.

Antipruriticsrelieve the discomfort sometimes associatedwith dry skin. Agents commonly used include corticoster-

oids, antihistamines and anesthetic agents.

Silicones: A Special Type of EmollientSilicones have been used in the cosmetic and toiletry indus-

try since the 1950s. The original use of the silicones was tominimize or prevent the whitening effect that occurred withthe use of soap-based skin lotions. Since that time, the use ofsilicones has expanded to all segments of the industry; andover 40% of all new cosmetic and toiletry products introducedtoday into the US market contain silicone. Five main groups ofsilicones are used: Cyclomethicones, Dimethicones, Silicone blends,

Dimethicone and vinyldimethicone crosspolymers, and Functional silicones.

The primary reason for the popular ity of the sil icones istheir sensory properties. Also, the silicones provide a greateremolliency effect than many commonly used cosmetic ingredi-ents. However, they have been slow to become readily incor-porated into many pharmaceutical preparations. The cyclo-methicones provide for transient effects of slight lubricity, alight texture, fast spreading and ease of distribution of theproduct upon application, meanwhile leaving no residual ef-fects. The cyclomethicones are often used to eliminate the

greasy or oily feel of hydrocarbon-based emollients and arethe reason for the oil-free claims of some products. The dimethicones are a higher-molecular-weight silicone and providemore lubrication and a longer-lasting effect. The dimethiconalso provide a richer and more pronounced skin treatment anare used in night and after-sun products.

All types of skin-care products, ranging from oil-in-watergels to oil-in-water and water-in-oil emulsions, and silicone-in-water and water-in-silicone emulsions, can contain siliconThe silicone preparat ions may be clear to white in color, de-pending upon the refractive index of the different phases.

Dosage Forms

Oil-in-Water EmulsionsThe most popular dosage forms used to treat dry skin have

been the oil-in-water emulsions (creams and lotions) becausethey tend to feel less greasy and are lower in cost due to their

high water content. However, it must be remembered thatthese emulsions contain surfactants that function to emulsifyoils. This can result in the emulsification of the skins oils andtheir removal from the skin upon repeated washing. The cyclof washing the hands, applying hand lotion, etc., results in aloss of the emollient natural oils in the skin, which complicatthe dry-skin condition.

Water-in-Oil EmulsionsEven though more effective, water-in-oil emulsions (cream

and lotions) have historically been less popular because of

Table 1. Ingredients That Can Be Used in Dry-SkinPreparations.

Class Example Percentage

Often Used

Emollients Mineral Oil 1 20

Lanolin Up to 50

Cetyl alcohol 2 5

Cyclomethicone Up to 50

Dimethicone Up to 30

Isopropyl myristate/palmitate 1 10

Petrolatum Up to 100

Hygroscopic Collagen Varies

Agents Glycerin Up to 30

Panthenol 2

Propylene glycol Up to 15

Protein, hydrolyzed Varies

Pyrrolidone-5-carboxylic acid 5Sodium hyaluronate 2

Sorbitol 3 15

Keratin-Softening Glycolic acida Up to 14

Agents Lactic acida 2 5

Ureaa 10 20

Antipruritics Hydrocortisone 1 2.5

a-hydroxy acids


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their greasy, oily feel upon application to the skin. Cold creamis an example that has been around for years but is often usedfor removal of makeup instead of treating dry skin. The avail-ability of newer emulsifiers has now made possible the prepa-ration of lighter water-in-oil emulsions that feel less greasy.

Oleaginous and Absorbent OintmentsOleaginous and absorption ointments are the most effect ive

in their emollient effect but also suffer from the inherentgreasiness associated with their use. However, if they are ap-plied at bedtime and remain on the skin overnight, they arevery effective.

GelsGels have a number of positive attributes that make them

very popular. For dry skin, oils and silicone have been emulsi-fied into gels to make them more useful in treating dry-skinconditions. Some gels are quite elegant and sparkling clear due

to the selection of ingredients of the same refractive index.Water-in-Silicone or Silicone-in-Water Emulsions

Emulsifiers for silicone have made possible the formulationof either water-in-silicone or silicone-in-water emulsions. Sili-cone has the advantage of staying on the skin much longer,since it is more difficult to remove with soap and water; there-fore, the protection is more prolonged.

SummaryThere are many formulat ions for the treatment of dry skin,

and patients often have their individual preferences. Using theformulations presented here, the compounding pharmacist canindividualize effective dry-skin formulations for his or her pa-tients by easily making changes, adding additional ingredients,

incorporating perfumes, etc.

Reference1. Spraycar M, ed. Stedmans Medical Dictionary. 26th ed. Baltimore,

MD:Williams & Wilkins; 1995:1967.

462International Journal of Pharmaceutical Compounding


Sample Formulas

Emollient-Type Formulas: Oleaginous and Absorption

Wool Alco hols Oint mentRx

For 100 g

Wool alcohols 6 g

Paraffin wax 24 g

White petrolatum 10 g

Mineral oil 60 g

Method of Preparation

Place the ingredients in a suitable container and heat until

ingredients are melted. Remove from heat and stir occasionally

until congealed. Package and label.

Water- Abso rbing Oi ntment

Rx

For 100 g

Cholesterol 3 g

Cottonseed oil 3 g



Heat the white petrolatum and cotton seed oil to about 145C.

Remove from heat, add the cholesterol and stir until congealed.

Package and label.

Natural Emollient Oil

Rx

For 100 g

Cocoa butter 40 g

Olive oil 30 mL

Wheat germ oil 30 mL


Using a water bath at very low temperature (35 to 40 C), heat the

ingredients in a suitable container. Mix well. Cool, packageand label.

Emulsion-Type FormulasThe following is a simple oil-in-water emulsion base that can be

easily modified by adding additional oils to enhance its emollient

properties.

Emulsion Base (Basic Formula for Individualizing)

Rx

For 100 g

Stearic acid 18 g

Cetyl alcohol 4 g

Triethanolamine 2 g

Glycerin 5 g

Purified water 71 gMethod of Preparation

Melt the stearic acid and cetyl alcohol together in a suitable vessel

to about 70C. Add the triethanolamine and glycerin to the purified

water and heat to about 70C. Add the aqueous solution to the

melted ingredients and mix well. Remove from heat and stir until

congealed. Package and label.

Tips for Patients on Restoring Dry Skinto Normal Avoid prolonged hot showers and baths. Use warm, not hot, water for bathing. Avoid excessive use of soap. Use soap primarily in armpit and groin areas and on

the feet. Increase humidity in the home by using humidifiers. Consume adequate water. Use appropriate emollients.

NOTE: When appl ying emoll ient preparations, apply withthe direction of hair growth, not against it, to prevent furtherirritation and damage to the skin. When drying, pat the skinwith the towel; dont rub.


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International Journal of Pharmaceutical Compounding


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Preparations That Can Serve as a Basis forEmollient CreamsThe following preparations can serve as a basis for many different emol-

lient creams. If the premixed oil phase is packaged in predeterminedsizes (for example, ice-cube-tray sizes), then it is very simple to obtain

the qua nti ty required for the ext emporaneo us prepar ati on. Add iti ona l

emollient ingredients can be easily added to individualize the preparation

for different patients. For example, the addition of any of the emollients

listed in Table 1 in their recommended percentages should work nicely.

Also, after the preparation has been mixed together, different fragrances

can be added as appropriate to further enhance the individuality of

the prepar ati on.

Premixed Oil Phase for Preparing Oil-in-Water Emulsions

Rx

For 100 g

Stearyl alcohol 53 g

Cetyl alcohol 7 g

Polyethylene glycol 300 38.6 g

Sodium lauryl sulfate 1.4 gMethod of Preparation

Melt the ingredients together and stir vigorously until completely mixed.

Remove from heat and mix occasionally until congealed.

Oil-in-Water Emulsion

Rx

For 100 g

Premixed oil phase for

oil-in-water emulsion 50 g

Purified water 50 g


Melt the premixed oil phase to about 70 to 75 C. Preheat the purified

water to about 70 to 75C. Remove from heat, mix the two together and

stir until the emulsion congeals. Package and label.

Lotions

Lotion with Cyclomethicone

Rx

For 100 g

Propylene glycol 25 mL

Triethanolamine 1 mL

Water 12 mL

Oleic acid 1.5 g

P ol ye thyl ene g ly co l 4 00 m onos tear at e 1 0. 5 g

Cyclomethicone 10 mL

Carbopol 934 2% gel 40 g


Mix the triethanolamine and propylene glycol with the water and heat to

about 70C. Mix the oleic acid, polyethylene glycol 400 monosterarate

and silicone fluid together and heat to about 70C. Mix the two toge ther,

remove from heat and mix while cooling. Incorporate into the Carbopol

934 2% gel and mix well. Package and label.

Lip-Balm Sticks

Water-Repe lling Lip-Balm Stick

Rx

For 100 g

Dimethicone 3 g

Menthol 500 mg

Vanillin 400 mg

Phenol crystals 100 mg

White wax 14 g

Cetyl esters wax 12 gWhite petrolatum 70 g


Heat the white wax, cetyl esters wax, dimethicone or silicone fluid and

white petrolatum together in a suitable container. Mix the menthol and

phenol together to form a eutectic. Remove the oil phase from the heat,

add the eutectic mixture followed by the vanillin and mix well while cool-

ing. While the mixture is still fluid, pour it into suitable medication sticks

and allow it to harden.

Lip-Balm Stick (Basic Formula for Individualizing)

Rx

For 100 g

White wax 15 g

Cetyl esters wax 15 g

White petrolatum 70 gMethod of Preparation

Using low heat, melt the ingredients in a suitable container and mix well.

Remove from heat and stir occasionally until congealed. While the

mixture is still fluid, pour it into suitable medication sticks and allow it

to harden.

Note: The ratios may need to be altered depending upon the amount of

liquids, solids and semisolids added to the formula.

Lip Ointments

Water-Repe lling Lip Oi ntment

Rx

For 100 g

Cyclomethicone 3 g

Menthol 500 mg

Vanillin 400 mg

Phenol crystals 100 mg

Cetyl esters wax 5 g

White wax 5 g



In a suitable container, melt the white wax and cetyl esters wax. Add the

white petrolatum and mix well. Add the cyclomethicone, remove from

heat and mix well. Form a eutectic with the menthol and phenol crystals

and add to the mixture. Incorporate the vanillin and mix well until

congealed.

Lip Ointment (Basic Ointment for Individualizing)

Rx

For 100 g

Cyclomethicone 3 gWhite wax 5 g

Lanolin 2 g



In a suitable container, melt the ingredients and mix well. Cool with mix-

ing until congealed. Package and label.

Note: The ratios may need to be altered depending upon the amount of

liquids, solids and semisolids added to the formula.

emulsion base to be individualized

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