Help physicians choose between different TOPICAL dosage forms

There are reasons to choose one topical dosage form over another. Tailor your choice based on skin type, the affected area, patient preference, and cost. And use these general rules of thumb...

 Creams work well for most areas, since they spread easily, vanish when rubbed in, and usually aren't greasy. For DRY skin, consider an ointment, their emollient effects help rehydrate skin. But caution that they may be sticky and stain clothes. For OILY skin, choose a gel, lotion, or foam, partly because they dry quickly and aren't greasy. Plus the alcohol in some products can have a drying effect on the skin. For SWEATY skin, keep in mind that powders can help absorb perspiration in areas such as on the feet or in skin folds. For the SCALP or HAIRY skin, try a gel, lotion, or foam. These spread easily and aren't greasy.

Be aware the dosage form can impact drug absorption, especially with corticosteroids. For example, betamethasone 0.05% (Diprosone) augmented ointment is VERY HIGH potency, the augmented cream is HIGH potency, and the non-augmented lotion is MEDIUM potency. Try to stick with similar dosage forms if you need to substitute a non-formulary topical product with a formulary option.

Table (1). Guide to Selecting Topical Dosage Forms
Dosage Form Non-greasy Easily Spread Quick-Drying Best for Skin Type Comments
Creams


(Usually non-greasy, but can be moderately greasy)


Most; hairy and non-hairy

Dry or sensitive

Exudative
Often preferred by patients

Moistening, emollient properties

Less hydrating than ointments

Provides no occlusion

Minimal residue
Ointments
Non-hairy

Very dry, thickened, scaly
Not generally preferred by patients

Occlusive, protective barrier

Messy, greasy: can stain clothing, etc

Hard to wash off

Emollient effects can rehydrate skin
Pastes
Non-hairy

Very dry, thickened, scaly
Thickest formulation

Messy, greasy: can stain clothing, etc

Hard to wash off

Not well absorbed, provides a protective barrier

Emollient effects can rehydrate skin

Starch-containing formulations can absorb secretions
Lotions


Hairy, scalp

Areas prone to chafing (e.g., groin, armpits, etc)

Face

Oily
Patients may like light feel

Drying effect

Cooling sensation, as it evaporates quickly

Doesn’t remain on the skin as well as creams and ointments

Good for large areas

Can use with make-up
Foams






Hairy, scalp

Inflamed, sensitive

Face

Oily
Improved patient adherence over traditional creams and ointments

Cooling sensation

Easy, quick application

Good skin absorption

Minimal residue

May be good if covering a large surface area

Can cause burning, stinging, pruritus less with alcohol-free foams

Fast penetration, high rate of total absorption

Can use with make-up
Gels






Face

Hairy, scalp

Oily
Often preferred by patients

Cooling sensation

Easy to wash off, including with perspiration

Alcohol-containing formulations can dry skin

Can use with make-up

Liquefy on contact with skin, forming a non-occlusive film

No emollient or skin protective properties

Fast release of the medication

Can cause burning, itching, dryness, irritation, peeling, redness

Some contain glycerin (promotes moisture retention) or dimethicone (emollient) to reduce irritation and increase hydration
Sprays






Most
Easy to use on large areas

Can cause erythema, scaling, dryness, stinging, burning
Powders




Exudative

Areas prone to chafing (e.g., groin, armpits, etc)
May be used to absorb secretions
Liquids (suspensions, solutions, etc)




Hairy Messy

No emollient, occlusion, or skin protective properties
These information from references...

IMPORTANT NOTE..
Estimating Dispensing and Application Amounts
  • Try using the Rule of Hand to help you calculate accurate amounts. One gram of cream will cover about four flat adult hands (wrist to fingertips with fingers together, i.e., four handprints). For example, a cream applied twice daily to an adult’s left forearm for 14 days would require about 14 g of cream. An adult hand covers roughly half of an adult’s forearm, so two flat hands = 0.5 g would cover the entire forearm one time. Therefore, you would need 0.5 g twice daily = 1 g per day for 14 days = 14 g total. Match this amount to the closest tube size of the cream being dispensed (e.g., 15 g, 20 g, etc). 
  • You can use the Fingertip Unit method to instruct patients on how much cream they should use per application and to help you determine the total amount to dispense. One fingertip unit is the amount of a topical preparation that can be squeezed out of a standard tube along an adult fingertip (fingertip to the crease of the first joint). One unit is enough to cover both sides of an adult hand with the fingers together. Use these estimates to figure out how much cream your patient should use per application: 2 units cover one adult foot; 2.5 units cover an adult face and neck; 3 units cover one adult arm (shoulder to wrist); 6 units cover one adult leg; 7 units cover an adult trunk (either front or back). One fingertip unit is about 0.5 g of cream... Four flat adult hands = two fingertip units = 1 g of cream.

REFERENCES

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