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Dermatologic
Therapeutics
Teresa O’Sullivan, PharmD, BCPS
University of Washington School of Pharmacy
Learning goal: a basic comfort level with choice of
agent, vehicle/route, directions, and duration of
therapy when prescribing medications for common
skin and eye conditions, plus what to consider when
someone presents with or is labeled as having
a drug allergy
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Online Videos
• Before presentation, you had an opportunity to view
videos on choosing products and multiple use agents.
• Please provide this feedback to your coursemaster,
after this presentation:
– Did you view videos and were they helpful? If you didn’t
have time to view the videos, that is useful information.
– Should more background information be provided online
prior to lecture with classroom time spent in problemsolving? If you do or don’t prefer to view online information
prior to classroom time, that is useful information.
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What are the characteristics of
these lesions?
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Treating atopic dermatitis
•
•
•
•
Avoid triggers
Soap substitutes?
Emollients after bath and prn (why?)
Mild exacerbation HC 1% BID until
lesion gone
• Infants: topical tacrolimus 0.03%
BID if HC needed
regularly or not
controlling adequately
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Treating atopic dermatitis
• Moderate exacerbation: med
potency ‘roid until lesions discrete
or 2-3 weeks; tacro/pimecrolimus
when at chronic stage
• Severe exacerbation: high potency
x 2 weeks;  to medium potency if
response; inadequate response?
consider Staph, add phototherapy,
or use immunomodulator
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What kind of lesion is this?
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Antipsoriatics
Used for: post-acute psoriatic lesion (to
induce/maintain remission)
Mechanism: inhibition of DNA synthesis (slow
down that cell division!)
Effect: onset 1-2 days; peak 3-5 days
Side effects: individualized per agent; see handout
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Antipsoriatics: agents
• Calcipotriene (vitamin D analog; well-tolerated)
• Methotrexate (good for psoriatic arthritis)
• Apremilast (Otezla®) titrate up to 30 mg po BID;
dbl response rate vs ADRs, DIs, $23K/yr
• For severe pustular/refractory psoriasis
dermatologist may use PUVA; etretinate, acitretin;
cyclosporine; alefacept, infliximab, etanercept
• Most patients with psoriasis will have other
systemic problems that you will need to treat
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Psoriasis: treatment plan
• Emollients for all
• Topical steroid for flare
– med potency for extensor; high potency (or
occlusion) if plaques thick, fluocinolone sol on
scalp, HC 1% intertrigenous areas
• Calcipotriene for maintenance (and flare)
• Methotrexate oral if joint involvement
• Refer to dermatologist if severe pustular/refractory
psoriasis
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What is this problem?
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What is this problem?
What does it have in common with
the previous slide?
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Antibacterials
Used for: acne, rosacea, small areas of superficial
cellulitis, conjunctivitis, BV
Mechanism: inhibition of bacterial protein synthesis
Effect: onset 24-48 hours; peak 3-5 days
Side effects: minimal; see individual agents
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Antibacterial agents
Skin infections
• Spectrum: bacitracin vs. triple antibiotic vs.
mupirocin
• Minor wounds: ointment application promotes
healing with less scarring than no ointment
• Oral cephalexin if area larger than a fingerprint;
TMP/SMX if abcess
• Mupirocin for catheter-related infections without
pus; chlorhexidene for prophylaxis
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Antibacterial agents
Burns
• Cool water
• Silver sulfadiazine protects and acts as antibiotic
• Apply 1/16 inch until eschar formation
• 20g small burns, 50g if area < 2" x 2", 400g for
larger areas
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Acne: the treatment plan
• Step 1: benzoyl peroxide (2.5% or 5% qOd initially) ; tea
tree oil if patient prefers “natural” product
• Step 2: topical erythromycin or clindamycin
• Step 3: oral antibiotic or oral contraceptive
– Doxycycline, erythromycin, SMX/TMP
– Tri-Levlen vs. other OCs vs. spironolactone
• Step 4: topical tretinoin
– Isotretinoin or etretinate should only be used for
severe cystic acne; iPledge program
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Antibacterial agents
Rosacea
1.
2.
3.
4.
Avoid triggers (vascular dilation),
use mild cleansers, sunscreen
Brimonodine 0.33% gel daily can
 erythema
Topical antibiotics for papules:
metronidazole 0.75% cream or
gel BID good initial therapy;
backup azelaic acid 20% cream,
15% gel BID
Oral antibiotics if unsatisfactory response to topical
therapy (tetra, erythro, doxy, metro)
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Antibacterial agents
Bacterial conjunctivitis
• Sodium sulfacetamide 10%
• Gentamicin, tobramycin
• Azithromycin, erythromycin
• Floxacins: cipro, levo, moxi, o, gati, besi
• Sig: 1 drop OU QID x 5 days
BV
• Oral metronidazole; can do vag gel but more
expensive; clindamycin vag gel if woman in 1st
trimester
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Identify these lesions
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Antifungals
Used for: athlete’s foot, ringworm, jock itch,
onychomycosis, thrush, vaginal yeast infection,
tinea versicolor
Mechanism: alteration of fungal cell membrane or
mitochondrial activity
Effect: onset 2-3 days; resolution 2-6 weeks
Side effects: rare with topical agents; oral azole drug
interactions
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Antifungal agents
• Dermal infections: OTC creams or powders;
fluconazole orally if treatment failure; selenium
sulfide topically for tinea versicolor
• Vaginal: clotrimazole or miconazole cream OTC;
butaconazole or terconazole (Rx); fluconazole single
dose
• Thrush: nystatin S&S; clotrimazole troches;
fluconazole oral; oral nystatin for baby and topical for
mom if breastfeeding infant thrush
• Nail: terbinafine AOC; itraconazole; griseofulvin if
drug interactions or cheap agent needed – 12+ weeks
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Identify these lesions
What do they have in common?
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Antivirals
Used for: warts, cold sores, shingles, chicken pox,
ocular viral infections
Mechanism: inhibits viral DNA replication
Effects: onset 2-3 days; 1-2 weeks for eradication
(longer for some infections)
Side effects: skin irritation with topical wart
products, otherwise rare
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Antiviral agents
• Warts: cryotherapy first line for plantar warts;
salicyclic acid (OTC) plasters or lotion; duct tape;
podophyllum or cantharidin applied in prescriber
office for genital warts
• Chicken pox/shingles: oral acyclovir x 5-10 days;
vaccine for chicken pox, shingles prevention
• Ocular viral infection: education/hygeine if URI;
trifluridine ophth soln for ocular herpes infection
• Cold sores: acyclovir or pencyclovir ointment
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What’s happening here?
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Head Lice Facts
• Infestations usually occur in autumn after start of
school and peak in Nov/Dec/Jan.
• Eggs hatch in 7-10 days; lice mature to adults in 1012 days; mature adults live as long as 40 days.
Females lay 6-7 eggs/day.
• Look for eggs near ears and in back of
head.
• Eggs/nits > 1/4 inch from hairline will
not be viable
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Head Lice Facts
• Mature lice easiest to locate in wet
hair.
• Mechanical removal with comb is
effective and should accompany
use of pediculocide; adult lice
white, brown, or dark gray: usually
have enough colour to be seen on
white tissue.
• Soak combs in isopropyl alcohol
after combing session.
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Treating Head Lice
• Products don’t penetrate nit shell well, + nits have no
nervous system x first 4 days, so pediculocide needs
residual activity or > 1 application
• Apply pediculocide to dry hair
• Avoid standard conditioners 2° impaired pediculocide
penetration in nymphs and adults
• No mayonnaise or petroleum jelly (messy, no evidence
of effectiveness)
• Mechanical removal crucial to eradication of
infestation; need fine-toothed nit or flea comb
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Antipediculocides
• Head lice:
– Permethrin (residual activity up to 10 days); check
for chrysanthemum or ragweed allergy
– 10-12 minute dwell time, rinse, then mechanical
removal with comb; may need 2nd application
– Rx: spinosad 0.9% suspension – same directions
• Scabies: permethrin (Elimite - Rx)
• Pinworms: pyrantel 5mg/lb single dose; OTC: several
brands (Antiminth, Pin-Rid, Pin-X)
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Topical chemotherapy
Used for: actinic keratosis (AK) and superficial skin
cancers
Mechanism: inhibits DNA synthesis (5-FU);  IL
production (masoprocol); immunomodulation
(imiquimod)
Effect: days to erythema; weeks to DC and resolution
Side effects: mild/moderate - severe skin irritation;
need sunscreen during treatment
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Actinic Keratosis (AK)
• Sun-induced; develops only
on sun-exposed skin
• Grayish-brown, discrete,
raised scaly lesions
• Cosmetically bothersome;
few convert to SCC, but
patient should watch and
report any  in lesion height,
size, or thickness
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Squamous Cell Carcinoma (SCC)
• Sun-induced; often develop
from AK
• Small oval nodule with
erythematous border;
sometimes with scab; may
appear in lip as fissure
• On backs of hands, face,
lower lip, ear, scalp
• Slow-growing; rarely
metastasize
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Basal Cell Carcinoma (BCC)
• Sun-induced; arsenic and
radiation also cause
• Small papule spreads outwards,
leaving central ulcer; edges raised
and pearl covered; persistent scab,
bleeding
• On face, particularly nose and
below eyes
• Slow-growing; rarely metastasize
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Topical chemotherapy agents
5-FU: AK, superficial basal cell
carcinoma (BCC); notable skin
irritation during application
Masoprocol: BID x 2-4 weeks for
AK; may stain clothes
Imiquimod: BID for AK,
superficial BCC
Diclofenac: BID x 2-3 months for
AK; less effective
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Malignant Melanoma
• Sun-influenced, not induced; genetic component
• Solitary pigmented lesions that initially look like
mole, then spread; can ulcerate and bleed
• Can occur anywhere on skin; generally
legs on females, back on males
• Can metastasize; deeper lesions carry
poor prognosis
• Requires surgical excision;
chemotherapy if metastatic
Remembering Stacey…
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Malignant Melanoma
Remember the dysplastic nevi / nodular melanoma alphabet
Asymmetry
Border irregularity
Color variation
Diameter (> pencil
eraser)
Evolving
Elevated
Firm to the touch
Growing
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Skin Cancer Treatment
• Topical therapy for AK; may be used also for superficial
SCC, BCC
• Surgical excision important for SCC, BCC, early
malignant melanoma
• Metastatic disease
– Platin tx for SCC, BCC
– Melanoma: goal is extra months of life
– Immunomodulators widely used: high-dose IFN, IL-2;
vemurafenib, ipilimumab therapy
– Dacarbazine monotherapy if patient can’t tolerate
immunomodulators
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Drug Allergy
• Pertinent to dermatology: the most common
allergic reactions involve the skin
• Common drug rashes: hives, maculopapular rash
• Some skin lesions that appear allergic may be nonallergic
– viral rashes
– non-allergic amoxicillin rashes
• One scary drug rash: Stevens-Johnson Syndrome/
TEN
– Allergic? Non-allergic? Does it matter?
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Drug Rashes: Hives
Urticaria
• Distribution: anywhere; usually appears first on
upper chest
• Appearance: pink and raised; larger lesions have
red border with paler interior
• Onset: minutes to hours; rarely > 12 hours
• Treatment: antihistamine
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Drug Rashes: Hives
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Drug Rashes: Maculopapular
Other descriptors: exanthematous, morbilliform
• Distribution: usually trunk first, often spares head
• Appearance: dusky to bright red, amorphous,
raised, itchy
• Onset: 12 - 48 hours
• Treatment: antihistamine, steroid if patient
frantically itchy
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Maculopapular drug rash
Note confluency of many lesions, toxic appearance
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Maculopapular Rash vs. Hives
Appearance is a little different
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Maculopapular Rash vs. Hives
Distribution is a little different
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Viral Rash
• Lesions
discrete
• preceding URI
highly likely
OR 20.5 (95%CI
5.2-94.5)
• rash very
common with
penicillin +
EBV
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Viral Rash versus Drug Rash
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Non-allergic Amoxicillin Rash
•
•
•
•
Occurs > day 3 of therapy
Lesions macular (more common) or maculopapular
Pruritis mild or absent
Rash duration ~ 3 days whether or not therapy
discontinued
• Not an allergy; rash won’t reappear with
readministration
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Stevens-Johnson Syndrome
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Stevens-Johnson Syndrome
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Stevens-Johnson Syndrome
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Cross-sensitivity
• Penicillins-cephalosporins:
– Traditional #s of 7-10% based on poor science
– Most common in drugs with similar side chains
– Can skin test (expired Pen G)  OK sens, good spec if
recent anaphylaxis; follow neg results w/2 small oral doses
• Sulfonamide antibiotics and other sulfonamides: no evidence of
cross-sensitivity in most people
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The Allergy Interview
• DISCERN (distribution, itchiness, shape,
confluency, elevation, redness (colour), number)
• Timing of reaction with regard to drug
administration
– How soon after therapy initiation?
– How long since most previous dose?
– How many times has drug been taken previously?
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Words to live by…
“all patients, regardless of drug allergy
status, should be supervised when
they take their first dose of any
medication, particularly an antibiotic”
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What Should Be Done?
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What Should Be Done?
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What Should Be Done?
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What Should Be Done?
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What Should Be Done?
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Thank you!!
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