Tracey C. Vlahovic, DPM FFPM RCPS (Glasg)

Clinical Professor,

Dept of Podiatric Medicine,

Temple Univ School of Podiatric Medicine,

Philadelphia, PA

None for this presentation

Ortho Dermatologics, Bako

Stratum corneum forms

the “skin barrier”

Corneocytes filled with keratin

Extracellular matrix - lipid

enriched

Protective wall

Regulates homeostasis – TEWL

Prevents the entry of

foreign particles and

pathogens into the body

Epidermis in Palm/Sole

Xerosis

Hyperkeratosis

Eczema/dermatitis

Atopic dermatitis

Lichen simplex chronicus

Dyshidrotic eczema

Wet to dry foot syndrome

Psoriasis

Lichen planus

Contact dermatitis

Stasis

edema/dermatitis/ulcer

Dermatophyte infection

= Skin Barrier Dysfunction

Lies within choosing the proper topical and active ingredient (Wolverton 2001)

The old rule in dermatology is “If a lesion is dry, wet it; if a lesion is wet, make it dry” BUT…!!!!

A vehicle can retard TEWL, increase flexibility of the skin, and stabilize the compound as well as drive it into the skin

A vehicle can make or break a formulation especially if sub-optimal vehicle used

Powder

Gel

Lotion

Cream

Foam

Spray

Tape

Emulsion

Solution

Lacquer

Topical Suspension

A Vehicle is the non-

active ingredient, but

impacts how the patient

tolerates the medicine

An IDEAL Vehicle is

odorless, non greasy,

easy to apply, non

irritating, inexpensive,

stable, cosmetically

elegant, and doesn’t

leave a residue

Ointment—most potent

Cream

Emollient cream

Gel

Lotion—most diluted

Spray

Tape

Foam

*Traditional thinking was that drugs had

to be occlusive (ointment) in order to get

the best penetration and efficacy

*Newer vehicles have changed our

mindset

*Changing vehicles can affect efficacy

Steps of percutaneous absorption of a topical:

A concentration gradient is initiated

Active drug moves out of the vehicle and into the skin

Active drug moves deeper into the skin and blood stream

By:

Controlling the partition characteristic between skin and vehicle

The vehicle itself may enter the skin and may affect diffusion

The vehicle may cause occlusion and drive the medication’s penetration

The release of the drug from the vehicle to the skin may control the rate of delivery

D Piacquadio and A Kligman, JAAD, 1998

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10 µm

10 µm10 µm

10 µm

10 µm

10 µm

H&E Untreated

Vaseline Dimethicone

Proderm ® Proderm ®

Ghadially R., abstract presented at 7th Annual Caribbean Dermatology

Symposium, St Thomas, US Virgin Islands, 2008

Pairing the correct vehicle/drug combination for the type of skin targeted as well as these factors:

Anatomy: interdigital vs hair baring skin vs large BSA vs plantar surface

WE DEAL WITH A MULTITUDE OF SKIN TYPES ON THE LOWER EXTREMITY: plantar, dorsal, hair bearing, interdigital, nails

Severity of skin disease (barrier disruption): Class 1 topical steroid vs the lower classes vs condition of the affected skin vs type of lesions present

Wet lesion vs dry lesion

Patient occupation, knowledge, and abillity

Palms and Soles need a topical with greater potency = ointment >>> solution, but not the most cosmetically elegant; also foam

Leg dermatitis: spray for spread-ability or lotion

Macerated interdigital = gel but what about a cream?

Moccassin tinea = cream/emollient/emulsion/spray?

Interdigital and Moccasin tinea = a combination of gel and cream or a topical suspension

Inflamed skin = increased absorption, so can use a less potent vehicle (ie liquid or cream)

Male vs. female preferences

Men may prefer gel, spray, or foam for their feet

because of applying socks

Women may prefer creams for moisturizing

Age related preferences

Younger patients may prefer gels, foams, sprays and

perceive it as a newer concept than cream

Which will lead to the best patient compliance??

What do you see?

If it is psoriasis, DO NOT USE oral steroids!!

Thou shalt not use Medrol Dose Packs

If acute eczema, use prednisone taper

If you can’t tell it’s psoriasis, biopsy

Don’t use a combination of antifungal and

corticosteroid!

Thou shalt not use Lotrisone (clotrimazole and

betamethasone)

Tinea incognito

What is it: fungal, bacterial, inflammatory?

Use the appropriate drug

What stage is it: acute, sub-acute, chronic?

Use the appropriate level of steroid

Other medical factors?

A reason to use topical over systemic?

Require topical or systemic therapy?

Chronic vs acute, severity

If you don’t know or treatment fails,

biopsy!!!

The first line is a topical corticosteroid:

Class I drugs should be used for 2 weeks to 1 month

with NO refills, remember side effects!

Titrate down

Prepare for flares

Add a barrier function cream

Goal: use little to no topical steroid ultimately

Class I steroids:

Clobetasol (Clobex, Olux, Temovate) Halobetasol (Ultravate)

Betamethasone (Diprolene) Fluocinonide (Vanos)

Diflorasone (Psorcon)

Class 1 Super Potent:

Class 2 Potent:

Class 3 Upper Mid-Strength:

Stein Gold L et al, J Drugs Dermatol. 2016 Mar 1;15(3):334-42.

Clobex Lotion/Spray/Shampoo, 0.05% Clobetasol propionate

Cormax Cream/Solution, 0.05% Clobetasol propionate

Diprolene Ointment, gel, lotion, 0.05% Betamethasone dipropionate

Olux E Foam, 0.05% Clobetasol propionate

Olux Foam, 0.05% Clobetasol propionate

Temovate Cream/Ointment/Solution,

0.05%

Clobetasol propionate

Diprolene Cream AF, 0.05% Betamethasone dipropionate

DFD-01 emollient Spray, 0.05%* Betamethasone dipropionate

Tazarotene Gel 0.1%

T + Diflorasone reduced atrophy by 37%

Ammonium lactate (AL)

AL + Clobetasol 35% decrease, 15% decrease occluded

Calcipotriene ointment

CP + BP Minimized atrophy in animal model

Kaidbey K, Int J Dermatol. 2001 Jul;40(7):468-71.

Lavker RM J Am Acad Dermatol. 1992 Apr;26(4):535-44.

S. Kurdykowski et al, poster EADV, 2012

Ointment (8 weeks)–70% marked improvement Skin irritation 10-15%

–11% clear

Cream–50% marked improvement Skin irritation 10-15%

–4% clear

Solution–31% marked improvement Skin irritation 1-5%

–14% clear

Foam–41% clear/almost clear scalp Skin irritation 2%

–14-27% clear/almost clear body

J Drugs Dermatol. 2016 Aug 1;15(8):951-7

Size, shape, charge, keratin binding, hydrophobicity

Nature of vehicle, pH, drug concentration

Nail properties: extent of hydration and disease condition

Kobayashi looked at 5-fluorouracil (hydrophilic) vs tolnaftate (lipophilic): tolnaftate had a low nail permeation because of its high molecular weight and low solubility in water

Urea in an aqueous solvent system denatured keratin and allowed permeation of the drug (swells the nail plate, too)

Chem Pharm Bull 46 (11) 1797-1802, 1998

Nail permeability decreases as the molecular

weight of the drug increases

BUT

Nail hydration facilitates diffusion: reduces

resistance of a slightly larger molecular weight,

but shouldn’t go above 350g/mol

J Control Release. 2015 Feb 10;199:132-44.

Nail is a hydrogel; with permeation depending

upon solubility in water or in a hydrated keratin

matrix

Solvents that promote diffusion through the skin,

don’t seem to work for the nail

The Above azoles are insoluble in water—

remember you need something hydrophilic!!

Adding urea to the mixture did not promote

passage of the azoles through

Drug Development and Industrial Pharmacy, Volume 24, Issue 7, January

1998, pages 685-690

Vehicles not only drive in the active ingredient, but can affect the skin barrier and efficacy of the medication

Choosing the right vehicle involves: anatomy, ptpreference, skin lesion, etc

With the lower extremity, we are dealing with hair bearing, plantar, interdigital, nails—which makes choosing the best topical more complicated

It’s about the steroid class, not the percentage!

Moisturizers should be part of your regimen

The nail is a hydrogel that is hydrophilic, so the same vehicles that are proven for the skin, may be ineffective for the nail

THANK YOU!!!! traceyv@temple.edu