Dermatologic Therapies Basic Dermatology Curriculum Last updated June 8, 2011 1 Module Instructions The following module contains a number of blue, underlined terms which are hyperlinked to the dermatology glossary, an illustrated guide to clinical dermatology and dermatopathology. We encourage the learner to read all the hyperlinked information. 2 Goals and Objectives The purpose of this module is to help medical students gain familiarity with common dermatologic treatments. By completing this module, the learner will be able to: • Estimate the amount of topical medication needed for therapy based on frequency of application and body surface area involved • Choose appropriate strengths of topical steroids based on age, body location and severity of dermatitis • List side effects of prolonged use of topical steroids • Discuss the basic principles of medications used to treat acne • Discuss the basic principles of topical antifungals, oral antihistamines and topical psoriasis medications 3 Principles of Dermatologic Therapy The efficacy of any topical medication is related to: • The active ingredient (inherent strength) • Anatomic location • The vehicle (the mode in which it is transported) • The concentration of the medication 4 Vehicles Foams Gels Creams Sprays Oils Solutions Ointments 5 Vehicles Ointments (e.g. Vaseline): lubricating, occlusive; greasy • USE for smooth, non-hairy skin; dry, thick, or hyperkeratotic lesions • AVOID on hairy and intertriginous (when skin is in contact with skin, e.g. armpits, groin, pannus) areas Creams (vanish when rubbed in): less greasy, drying effects; not occlusive, can sting, more likely to cause irritation (preservatives/fragrances) • USE for acute exudative inflammation, intertriginous areas Lotion (pourable liquid): less greasy, less occlusive; may contain alcohol (drying effect on oozing lesion); penetrate easily, little residue • USE for hairy areas 6 Vehicles (cont.) Oils: less stinging than lotions or solutions • USE for the scalp, especially for people with coarse or very curly hair Gel (jelly-like): may contain alcohol, greaseless, least occlusive; dry quickly • USE for acne, exudative inflammation (e.g. acute contact dermatitis); on scalp/hairy areas without matting Foams (cosmetically elegant): spread readily, easier to apply; more expensive • USE for hairy areas; inflammation • Sprays: Aerosols (rarely used), pump sprays 7 Medication Costs Topical medications can be very expensive They are not all covered by insurance Over the counter (OTC) treatments are generally cheaper than prescriptions Generics are less expensive than brand name prescriptions It is helpful to know the costs of the medications you prescribe and be able to tell the patient in advance what they should expect to pay 8 What goes into a topical prescription? 9 Topical prescriptions What goes into a prescription? • Desonide cream 0.05% apply to affected area (face) BID PRN for scaling #15 Grams RF3 10 Topical prescriptions What goes into a prescription? • Desonide cream 0.05% apply to affected area (face) BID PRN for scaling #15 Grams RF3 • Generic name 11 Topical prescriptions What goes into a prescription? • Desonide cream 0.05% apply to affected area (face) BID PRN for scaling #15 Grams RF3 • Generic name • Vehicle 12 Topical prescriptions What goes into a prescription? • Desonide cream 0.05% apply to affected area (face) BID PRN for scaling #15 Grams RF3 • Generic name • Vehicle • Concentration 13 Topical prescriptions What goes into a prescription? • Desonide cream 0.05% apply to affected area (face) BID PRN for scaling #15 Grams RF3 • Generic name • Vehicle • Concentration • Sig (directions) 14 Topical prescriptions What goes into a prescription? • Desonide cream 0.05% apply to affected area (face) BID PRN for scaling #15 Grams RF3 • Generic name • Vehicle • Concentration • Sig • Amount 15 Topical prescriptions What goes into a prescription? • Desonide cream 0.05% apply to affected area (face) BID PRN for scaling #15 Grams RF3 • Generic name • Vehicle • Concentration • Sig • Amount • Refills 16 Now Let’s Review Some Common Types of Medications Used by Dermatologists 17 Topical Corticosteroids Topical steroids produce an antiinflammatory response in the skin They are effective for conditions that are characterized by hyperproliferation, inflammation, and immunologic involvement They can also provide symptomatic relief for burning and pruritic lesions 18 Topical Corticosteroids Corticosteroids are organized into classes based on their strength (potency) • Therefore, steroids within any class are equivalent in strength Strength is inherent to the molecule, not the concentration Know one steroid from each class that would be available to the majority of your patients (the generic in that class) 19 Topical Steroid Strength Potency Class Example Agent Super high I Clobetasol propionate 0.05% High II Fluocinonide 0.05% III – V Triamcinolone acetonide ointment 0.1% Triamcinolone acetonide cream 0.1% Triamcinolone acetonide lotion 0.1% VI – VII Fluocinolone acetonide 0.01% Desonide 0.05% Hydrocortisone 1% Medium Low 20 Topical Steroid Strength Remember to look at the class not the percentage • Note that clobetasol 0.05% is stronger than hydrocortisone 1%. When several are listed, they are listed in order of strength • Note that triamcinolone ointment is stronger than triamcinolone cream or lotion because of the nature of the vehicle Potency Class Super high I Clobetasol 0.05% High II Fluocinonide 0.05% III – V Triamcinolone ointment 0.1% Triamcinolone cream 0.1% Triamcinolone lotion 0.1% VI – VII Fluocinolone 0.01% Desonide 0.05% Hydrocortisone 1% Medium Low Example Agent 21 Corticosteroid Selection Super high potency (Class I) are used for severe dermatoses over nonfacial and nonintertriginous areas • Scalp, palms, soles, and thick plaques on extensor surfaces Medium to high potency steroids (Classes II-V) are appropriate for mild to moderate nonfacial and nonintertriginous areas • Okay to use on flexural surfaces for limited periods Low potency steroids (Classes VI, VII) can be used for large areas and on thinner skin • Face, eyelid, genital and intertriginous areas 22 Local Side Effects of Topical Steroids Local side effects of topical steroids include: • Skin atrophy • Telangiectasias • Striae • Acne • Steroid Rosacea • Hypopigmentation The higher the potency the more likely side effects are to occur. To reduce risk, the least potent steroid should be used for the shortest time, while still maintaining effectiveness 23 Local Corticosteroid Skin Side Effects Skin Atrophy Striae 24 Local Corticosteroid Skin Side Effects Hypopigmentation 25 Systemic Side Effects of Topical Steroids Systemic side effects are rare due to low absorption They can include: • • • • • Glaucoma (when steroid applied to the eyelid) Hypothalamic pituitary axis suppression Cushing’s syndrome Hypertension Hyperglycemia The higher the potency the more likely side effects are to occur To reduce risk, the least potent steroid should be used for the shortest time, while still maintaining effectiveness 26 Duration of Treatment Duration of treatment is limited by side effects In general: • Super high potency: treat for <3 weeks • High and Medium potency: <6-8 weeks • Low potency: side effects are rare. Treat facial, intertriginous, and genital dermatoses for 1-2 week intervals to avoid skin atrophy, telangiectasia, and steroid-induced acne Stop treatment when skin condition resolves • To avoid rebound/flares: taper with gradual reduction of both potency and dosing frequency every 2 weeks If the patient does not respond to treatment within these guidelines, consider referral to a dermatologist 27 Prescribing topical steroids The following slides will review how to estimate the amount of medication to prescribe according to the affected body surface area (BSA) 28 Estimating BSA: Palm of Hand 1 Palm = 1% BSA Use the size of the patient’s palm, not your own 29 Estimating topicals: Fingertip unit Quantity of topical medication (dispensed from a 5mm nozzle) placed on pad of the index finger from distal tip to DIP joint Fingertip unit (FTU) = 500 mg = treats 2% BSA 30 2 palms 2 times a day = 30 grams / mo 1 Palm = 1% BSA 1 Palm = 1% BSA FTU = 0.5 G Covers 2 % BSA Covers 2 palms 2 palms = 2% BSA 2 palms 2 times per day = 1 gram per day SO…GIVE 30 GRAMS FOR EVERY 2 PALMS OF AREA TO COVER (FOR 1 MONTH Rx) 31 Practice Question 1 Take a look at the following photograph and decide how much BSA is affected. Then try to answer the question on the following slide. 32 Practice Question Which of the following prescriptions would you recommend for BID dosing for 1 month duration? Use 2% BSA. a. Fluocinonide 0.05% ointment, apply to affected area (knees) BID, # 30 grams b. Fluocinonide 0.05% ointment, apply to affected area (knees) BID, # 90 grams c. Hydrocortisone 1% ointment, apply to affected area (knees) BID, # 30 grams d. Hydrocortisone 1% ointment, apply to affected area (knees) BID, # 90 grams 33 Practice Question Which of the following prescriptions would you recommend for BID dosing for 1 month duration? Use 2% BSA. a. Fluocinonide 0.05% ointment, apply to affected area (knees) BID, # 30 grams (2 palms = 2% BSA = 30 grams for 1 mo BID) b. Fluocinonide 0.05% ointment, apply to affected area (knees) BID, # 90 grams (for a 3 month supply) c. Hydrocortisone 1% ointment, apply to affected area (knees) BID, # 30 grams (need a higher potency steroid for plaque psoriasis on the knees) d. Hydrocortisone 1% ointment, apply to affected area (knees) BID, # 90 grams 34 Estimating amounts It takes ~30 grams to cover an average adult body (for one application) Here is a rough estimation of amounts to prescribe for BID use for a month: • Face • 30-45 grams • Extensor surfaces of both arms • 120-150 grams • Widespread on trunk, legs, arms: • 1-2 pounds (454 grams = 1 lb.) 35 Estimating amounts: re-assess of follow-up The best way to assure you are giving the right amount is to re-assess on follow-up • If your patient was given a 60-gram tube, confirm they are using it according to instructions, and ask how long that tube lasts • If a 60-gram tube only lasts them 2 weeks, they need 2 of them to last a month 36 Estimating BSA: Rule of Nines The “rule of nines” is a good, quick way of estimating the affected BSA Often used when assessing burns The body is divided into areas of 9% Less accurate in children Source: McPhee SJ, Papadakis MA: Current Medical Diagnosis and Treatment 2010, 49th Edition: http://www.accessmedicine.com. Copyright © The McGraw-Hill Companies, Inc. 37 Pediatric Dosing Children require adjusted dosage Use a pediatric version of the rule of nines or the patient’s palm to estimate BSA Remember that children, especially infants have a high body surface area to volume ratio, which puts them at risk for systemic absorption of topically applied medications 38 Pediatric Dosing (cont.) Low potency topical corticosteroids are safe when used for short intervals • Can cause side effects when used for extended durations High potency steroids must be used with caution and vigilant clinical monitoring for side effects in children Potent steroids should be avoided in high risk areas such as the face, folds, or occluded areas such as under the diaper 39 Let’s move on to some more types of medications used by dermatologists Medications commonly used to treat Acne vulgaris 40 Benzoyl peroxide Benzoyl peroxide is a topical medication with both antibacterial and comedolytic (breaks up comedones) properties Available as a prescription and over-the-counter, as well as in combinations with topical antibiotics Patients should be warned of common adverse effects: • Bleaching of hair, colored fabric, or carpet • May irritate skin; discontinue if severe Available as a cream, lotion, gel, or wash 41 Topical Antibiotics Used to reduce the number of P. acnes and reduce inflammation in inflammatory acne Do not use as monotherapy (often used with benzoyl peroxide to prevent the development of antibiotic resistance in the treatment of mild-tomoderate acne and rosacea) • Erythromycin 2% (solution, gel) • Clindamycin 1% (lotion, solution, gel, foam) Metronidazole 0.75%, 1% (cream, gel) is used in the treatment of rosacea 42 Topical Retinoids (tretinoin, all trans retinoic acid) Topical retinoids are vitamin A derivatives Used for acne vulgaris; photodamaged skin; fine wrinkles, hyperpigmentation Patients should be warned of common adverse effects: • Dryness, pruritus, erythema, scaling • Photosensitivity Available as a cream or gel Do not apply at the same time as benzoyl peroxide because benzoyl peroxide oxidizes tretinoin 43 Topical Acne Treatment: Side Effects Topical acne treatments are often irritating and can cause dry skin • When using retinoids or benzoyl peroxide, consider beginning on alternate days. Use a moisturizer to reduce their irritancy. Topical agents take 2-3 months to see effect Patients will often stop their topical treatment too early from “red, flakey” skin without improvement in their acne Patient education is a crucial component to acne treatment 44 Oral Antibiotics Tetracycline, doxycycline, minocycline Use for moderate to severe inflammatory acne Often combined with benzoyl peroxide to prevent antibiotic resistance If the patient has not responded after 3 months of therapy with an oral antibiotic, consider: • Increasing the dose, • Changing the treatment, or • Referring to a dermatologist 45 Oral Treatment: Side Effects Tetracyclines (tetracycline, doxycycline, minocycline): • Are contraindicated in pregnancy and children age <8 years • May cause GI upset (epigastric burning, nausea, vomiting and diarrhea can occur) • Can cause photosensitivity (patients may burn easier, which can be easily managed with better sun protection). Recommend sun block with UVA coverage for all acne patients on tetracyclines 46 Oral Tetracyclines: Patient Counseling Major side effects: • Tetracycline: GI upset, photosensitivity • Doxycycline: GI upset, photosensitivity • Minocycline: GI upset, vertigo, hyperpigmentation Patients need clear instructions • If taking for acne, it is okay to take them with food and dairy products for tolerability of GI side effects • Take with full glass of water; avoids esophageal erosions • Tetracyclines do NOT interfere with birth control pills • It takes 2-3 months to see improvement 47 Oral Isotretinoin Oral isotretinoin, a retinoic acid derivative, is indicated in severe, nodulocystic acne failing other therapies Should be prescribed by physicians with experience using this medication Typically given in a single 5-6 month course Isotretinoin is teratogenic and therefore absolutely contraindicated in pregnancy • Female patients must be enrolled in a FDA-mandated prescribing program in order to use this medication • Two forms of contraception must be used during isotretinoin therapy and for one month after treatment has ended 48 Isotretinoin Side Effects Common side effects of isotretinoin include: • • • • Xerosis (dry skin) Cheilitis (chapped lips) Elevated liver enzymes Hypertriglyceridemia Individuals with severe acne may suffer mood changes and depression and should be monitored Severe headache can be a manifestation of the uncommon side effect pseudotumor cerebri 49 Topical Antifungals 50 Topical Antifungals There are several classes of topical antifungal medications Some classes are fungistatic (stop fungi from growing), others are fungicidal (they kill the fungi) Not all conditions are treatable with topical antifungals (specifically, hair infections and nail infections do not respond to topical treatment and require systemic treatment) 51 Topical Antifungals The following are some examples of topical antifungals: • Imidazoles (fungistatic): Ketoconazole (Rx & OTC), Econazole, Oxiconazole, Sulconazole, Clotrimazole (Rx & OTC), Miconazole (OTC) – Useful to treat candida and dermatophytes • Allylamines and benzylamines (fungicidal): Naftifine, Terbinafine (OTC), Butenafine – Better for dermatophytes, but not candida • Polyenes (fungistatic in low concentrations): Nystatin – Better for candida, but not dermatophytes 52 Advantages of Topical Antifungals Topical antifungals are preferred for most superficial fungal infections of limited extent. Advantages include: • • • • Relatively low cost Acceptable efficacy Ease of use Low potential for side effects, complications, or drug interactions 53 Oral Antihistamines 54 Antihistamines Antihistamines are the most widely used agents for pruritus and chronic urticaria 1st Generation H1 antagonists are sedating • Anticholinergic side effects (e.g. memory impairment, confusion, dry mouth, blurred vision) are dose-limiting • Use as a sleep aid at night for patients with pruritus • Use with caution in elderly due to increased fall risk, CNS and anticholinergic effects 2nd Generation H1 antagonists are minimally sedating and require less frequent dosing than 1st generation H1 antihistamines 55 Antihistamines The following are examples of H1 antihistamines: • 1st Generation • 2nd Generation • Diphenhydramine (OTC) • Cetirizine (OTC) • Hydroxyzine (Rx, generic) • Loratadine (OTC) • Chlorpheniramine (OTC) • Fexofenadine (OTC) For most pruritic dermatoses that are not urticaria, 1st generation H1 antihistamines primarily work through their sedative effect rather than their anti-histaminic properties 56 Medications used in Psoriasis 57 Skin Kinetics Some dermatoses are associated with a higher rate of epidermal turnover • For example, the epidermis of psoriasis replicates too quickly Topical therapies that inhibit keratinocyte proliferation are used in the treatment of psoriasis They include: • Vitamin D analogs • Coal tar • Tazarotene 58 Psoriasis Treatment: Topical Vitamin D Analogs Calcipotriene (calcipotriol) • Inhibits keratinocyte proliferation • Most common side effect is skin irritation Calcitriol • Inhibits keratinocyte proliferation • Stimulates keratinocyte differentiation • Inhibits T-cell proliferation • On more sensitive areas, less skin irritation than calcipotriol 59 Psoriasis Treatment Tar 2-5% • Antiproliferative effect • Disadvantages: stain clothing/hair/skin; messy; increases photosensitivity • Can be combined with salicylic acid to penetrate thick plaques Tazarotene 0.05% and 0.1% • • • Topical retinoid used for acne, rosacea, psoriasis Disadvantages: skin irritation; teratogenic; increases photosensitivity Can be combined with a Class II corticosteroid to reduce irritation 60 Take Home Points The efficacy of any topical medication is related to the strength, location, vehicle, and concentration Topical medications can be very expensive When writing a prescription for a topical medication, include: generic name, vehicle, concentration, directions, amount, # of refills Corticosteroids are organized into classes based on their strength (potency) Skin atrophy, acne, striae, and telangiectasias are potential local side effects of corticosteroid use It takes ~30 grams to cover an average adult body (for one application) 61 Take Home Points Use benzoyl peroxide with topical antibiotics to prevent the development of antibiotic resistance in acne treatment Lack of adherence is the most common cause of treatment failure in acne patients; patient education is crucial Topical antifungals are preferred for most superficial fungal infections of limited extent Antihistamines are the most widely used agents for pruritus and chronic urticaria 2nd Generation H1 antihistamines are less sedating that 1st generation H1 antihistamines Many of the topical medications used in psoriasis inhibit keratinocyte proliferation 62 Acknowledgements This module was developed by the American Academy of Dermatology Medical Student Core Curriculum Workgroup from 2008-2012. Primary authors: Alina Markova, Sarah D. Cipriano, MD, MPH; Timothy G. Berger, MD, FAAD; Patrick McCleskey, MD, FAAD. Peer reviewers: Peter A. Lio, MD, FAAD; Ron Birnbaum, MD. Revisions: Sarah D. Cipriano, MD, MPH. Last revised June, 2011. 63 References Berger T, Hong J, Saeed S, Colaco S, Tsang M, Kasper R. The WebBased Illustrated Clinical Dermatology Glossary. MedEdPORTAL; 2007. Available from: www.mededportal.org/publication/462. Drake LA, Dinehart SM, Farmer ER, et al. Guidelines of care for the use of topical glucocorticosteroids. American Academy of Dermatology. J Am Acad Dermatol 1996; 35:615. Ference J, Last A. Choosing Topical Corticosteroids. Am Fam Physician 2009;79 (2):135-140. Goldstein B, Goldstein A. General principles of dermatologic therapy and topical corticosteroid use. In: UpToDate, Basow, DS (Ed), UpToDate, Waltham, MA, 2011. Hettiaratchy S, Papini R. ABC of burns. Initial management of a major burn: II – assessment and resuscitation. BMJ. 2004;329:101-103. 64 References High Whitney A, Fitzpatrick James E, "Chapter 219. Topical Antifungal Agents" (Chapter). Wolff K, Goldsmith LA, Katz SI, Gilchrest B, Paller AS, Leffell DJ: Fitzpatrick's Dermatology in General Medicine, 7e: http://www.accessmedicine.com/content.aspx?aID=2969866. Limb Susan L, Wood Robert A, "Chapter 230. Antihistamines" (Chapter). Wolff K, Goldsmith LA, Katz SI, Gilchrest B, Paller AS, Leffell DJ: Fitzpatrick's Dermatology in General Medicine, 7e: http://www.accessmedicine.com/content.aspx?aID=3003116. Nelson A, Miller A, Fleischer A, Balkrishnan R, Feldman S. How much of a topical agent should be prescribed for children of different sizes? J Derm Treat 2006; 17:224-228. Weller R, Hunter J, Dahl M. Clinical Dermatology. 2008; 55. Wolff K, Johnson R. Fitzpatrick’s Atlas of & Synopsis of Clinical Dermatology. 2009; Sixth Ed. 65