Dermatologic therapies - American Academy of Dermatology

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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.
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