Week 5: Agents Used to Treat Acne Flashcards
First-line therapy for acne vulgaris with closed comedones includes:
a) oral antibiotics
b) isotretinoin
c) benzoyl peroxide
d) hydrocortisone cream
C - Benzoyl peroxide - can be used as monotherapy
Benzoyl peroxide mechanism of action
- antibacterial against P Acne
- releases active or free radical O2 to oxidize bacteria
- drying effect, removes extra sebum
- causes mild desquamation
Benzoyl peroxide ADRs
- dryness, peeling, irritation
- photosensitivity
- can bleach clothes, sheets, towels
Benzoyl peroxide Precautions/Contraindications
- safe for use in pregnancy
- BP applied AM, retinoid applied PM
Erythromycin topical mechanism of action
- topical antibiotic
- a bacteriostatic macrolide antibiotic which interrupt protein synthesis at the 50S ribosomal subunit
- combo with BP = reduce bacterial resistance
Erythromycin topical Precautions/Contraindications
- safe in pregnancy
- better tolerated than Clindamycin
- don’t use with clindamycin
Clindamycin topical (topical antibiotic) ADR
- burning and irritation
- diarrhea / colitis (rare) monitor !
Azelaic acid (topical antibiotic) ADRs
- skin hypopigmentation may occur
- avoid in people with color
Azelaic acid Precautions/Contrainindictions
- Pregnancy Category B
- absorbed systemically even when applied in small amounts so may be excreted in breast milk
- caution in lactating women
TRUE or FALSE
It is not appropriate to use Benzoyl Peroxide and either Clindamycin or Erythromycin on the same patient
FALSE - it is appropriate to be used on the same patient simultaneously - but the two products should be used at a different time of day (one medication in the morning and the other medication in the evening)
Isotretinoin (Accutane) Mechanism of Action
- systemic retinoid
- used for severe nodular cystic acne
- reduces sebaceous gland size & sebum
- normalizes follicular keratinization
- reduces P Acne
Isotretinoin (Accutane) Precautions/Contraindications
- pregnancy category X
- must verify the patient is not pregnant or trying to get pregnant before giving
- should not be used in patients at risk for osteoporosis
- NO ALCOHOL
Isotretinoin (Accutane) ADRs
- cheilitis (drying, peeling skin)
- photosensitivity
- lethargy/fatigue
- arthralgias/myalgias
- hypertriglycerdemia (LFTs)
- mood changes
- SI, mood swings, depression
Tretinoin (Retin-A) [topical retinoid] - mechanism of action
- decreases the cohesion between the epithelial cells and follicular cells of the hair
- expulsion of comedomes and prevent new ones
- NO antibiotic properties, but can enhance the penetration of other topical agents such as benzoyl peroxide
When prescribing tretinoin (Retin-A), the nurse practitioner (NP) advises the patient to:
a) use it with benzoyl peroxide to minimize irritating effects
b) use a sunscreen because the drug is photosensitzing
c) add a sulfa-based cream to enhance anti-acne effects
d) expect a significant improvement in acne lesions after approximately 1 week of use
B - use a sunscreen because the drug is photosensitizing
- can also cause hypopigmentation
Tretinoin (Retin-A) cautions
- pregnancy category C -
- thin layer is all that is needed
- caution in lactation, sensitive skin pts, eczema, skin abrasions, sunburn
What are some important things to educate your patient on when using topical medications for acne?
- Your acne may get worse before it gets better. Benefits may take 6-8 weeks to appear.
- Use sunscreen.
- Topical retinoids should not be used at the same time of day as topical antibiotics.
All topical retinoids should be avoided in what patient conditions?
- eczema, sunburn, or skin abrasions at the site of application
You prescribe a topical medication and want it to have maximum absorption, so you choose the following vehicle:
a) gel
b) lotion
c) cream
d) ointment
D - ointments - more occlusive, so more potent
creams are less occlusive, so less potent and lotions are the lease potent
You write a prescription for a topical agent and anticipate the greatest rate of absorption when it is applied to the:
a) palms of the hands
b) soles of the feet
c) face
d) abdomen
C - face
One of the mechanisms of action of a topical corticosteroid preparation is as:
a) an antimitotic
b) an exfoliant
c) a vasoconstrictor
d) humectant
C - a vasoconstrictor
To enhance the potency of a topical corticosteroid, the prescriber recommends that the patient apply the preparation:
a) to dry skin by gentle rubbing
b) and cover with an occlusive dressing
c) before bathing
d) with an emollient
B - and cover with an occlusive dressing
Which of the following is the least potent topical corticosteroid?
a) betamethasone dipropionate 0.1% (Diprosone)
b) clobetasol propionate 0.05% (Cormax)
c) hydrocortisone 2.5%
d) fluocinonide 0.05% (Lidex)
C - hydrocortisone 2.5%
Topical corticosteroid MOA & Classes
- anti-inflammatory, antipruritic, and vasoconstriction properties
- used for dermatitis, psoriasis, eczema
Class I - very high strength
Class II and III - high strength
Class IV and V - intermediate strength
Class VI and VII - low strength