Week 5: Agents Used to Treat Acne

Question 1

First-line therapy for acne vulgaris with closed comedones includes:

a) oral antibiotics
b) isotretinoin
c) benzoyl peroxide
d) hydrocortisone cream

Answer 1

C - Benzoyl peroxide - can be used as monotherapy

Question 2

Benzoyl peroxide mechanism of action

Answer 2

• true comeolytic (mild) and antibacterial action
• dekeratinizes the hair follicle and decreases the cohesion between the epithelial cells and follicular cells of the hair - when this happens the oil, WBC, bacteria, old skin cells can get out of the follicle
• also kills bacteria

Question 3

Benzoyl peroxide ADRs

Answer 3

• dryness, peeling, irritation
• photosensitivity
• can bleach clothes, sheets, towels

Question 4

Benzoyl peroxide Precautions/Contraindications

Answer 4

• safe for use in pregnancy

- should not be applied at the same time as topical retinoids (apply this in the AM and retinoids in the PM)

Question 5

Erythromycin topical mechanism of action

Answer 5

• topical antibiotic - a bacteriostatic macrolide antibiotic which binds to the P site of the 50S ribosomal subunit, interfering with protein synthesis

Question 6

Erythromycin topical Precautions/Contraindications

Answer 6

• safe in pregnancy

- better tolerated than Clindamycin

Question 7

Clindamycin topical (topical antibiotic) ADR

Answer 7

• burning and irritation

- diarrhea / colitis (rare)

Question 8

Azelaic acid (topical antibiotic) ADRs

Answer 8

• skin hypopigmentation may occur - avoid in people with color

Question 9

Azelaic acid Precautions/Contraidictions

Answer 9

• Pregnancy Category B
• absorbed systemically even when applied in small amounts so may be excreted in breast milk - caution should be used in lactating women

Question 10

TRUE or FALSE

It is not appropriate to use Benzoyl Peroxide and either Clindamycin or Erythromycin on the same patient

Answer 10

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)

Question 11

Isotretinoin (Accutane) Mechanism of Action

Answer 11

• systemic retinoid - prodrug of Retin-A
• potent comeolytic
• reduces sebum production
• reduces sebaceous gland size
• normalizes follicular keratinization
• used for severe nodular cystic acne

Question 12

Isotretinoin (Accutane) Precautions/Contraindications

Answer 12

• 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

Question 13

Isotretinoin (Accutane) ADRs

Answer 13

• drying, peeling skin redness
• photosensitivity
• lethargy/fatigue
• arthralgias/myalgias
• mood changes - SI, mood swings, depression

Question 14

Tretinoin (Retin-A) [topical retinoid] - mechanism of action

Answer 14

• potent comeolytic - de-keratinizes the hair follicle and decreases the cohesion between the epithelial cells and follicular cells of the hair
• does not have antibiotic properties, but can enhance the penetration of other topical agents such as benzoyl peroxide

Question 15

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

Answer 15

B - use a sunscreen because the drug is photosensitizing

- can also cause hypopigmentation

Question 16

Tretinoin (Retin-A) cautions

Answer 16

• pregnancy category C -
• thin layer is all that is needed
• never use as monotherapy

Question 17

What are some important things to educate your patient on when using topical medications for acne?

Answer 17

• 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.

Question 18

All topical retinoids should be avoided in what patient conditions?

Answer 18

• eczema, sunburn, or skin abrasions at the site of application

Question 19

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

Answer 19

D - ointments - more occlusive, so more potent

creams are less occlusive, so less potent and lotions are the lease potent

Question 20

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

Answer 20

C - face

Question 21

One of the mechanisms of action of a topical corticosteroid preparation is as:

a) an antimitotic
b) an exfoliant
c) a vasoconstrictor
d) humectant

Answer 21

C - a vasoconstrictor

Question 22

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

Answer 22

B - and cover with an occlusive dressing

Question 23

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)

Answer 23

C - hydrocortisone 2.5%

Question 24

Topical corticosteroid MOA & Classes

Answer 24

- 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

Question 25

Topical corticosteroid Cautions/Contraindications

Answer 25

- do not use high-potency agents on face, palms, feet, groin, axilla - caution in pregnant patients; only use if benefits outweigh the risks - children are often more susceptible to the effects and require the lowest effective strength to be used

Question 26

Topical corticosteroid ADRs

Answer 26

- local skin irritation - increase in the risk for secondary infections - tolerance may occur with prolonged used - adrenal function should be monitored - do not stop drug abruptly

Question 27

Topical calcineurin inhibitors "limus" (Pimecrolimus/Elidel and Tacrolimus/Protopic) Indications and MOA

Answer 27

- atopic dermatitis/eczema - much more potent anti-immunologic and immunosuppressive - these are NOT STEROIDS - suppresses cellular immunity through inhibiting T-cell activation by binding to intracellular proteins, including calcineurin-dependent proteins. This results in inhibition of inflammatory cytokines and mediators from mast cells

Question 28

Topical calcineurin inhibitor cautions and contraindications

Answer 28

- black box warning for long-term safety concern because of rare cases of malignancy - skin cancer - do not use occlusive dressing over this drug (do not use in the diaper area) - both should be avoided in children younger than two years and in immunosuppressed patients

Question 29

Situations when to use of topical calcineurin inhibitors

Answer 29

- atopic dermatitis that is resistant to steroids - sensive areas like face, skin folds Elidel - approved for mild to moderate disease Protopic - approved for moderate to severe disease

Question 30

Topical calcineurin inhibitor ADRs

Answer 30

- local reaction at site of application - burning, pruritus and tingling - H/A, fever, flu-like symptoms

Question 31

In the treatment of acne vulgaris, which lesions respond best to topical antibiotic therapy? a) open comedones b) cysts c) inflammatory lesions d) superficial lesions

Answer 31

C - inflammatory lesions

Question 32

You have initiated therapy for an 18-year-old man with acne vulgaris and have prescribed doxycycline. He returns in 3 weeks, complaining that his skin is "no better." Your next action is to: a) counsel him that 6 to 8 weeks of treatment is often needed before significant improvement is achieved b) discontinue the doxycycline and initiate minocycline therapy c) advise him that antibiotics are likely not an effective treatment for him and should not be continued d) add a second antimicrobial agent such as trimethoprim-sulfamethoxazole

Answer 32

A - counsel him that 6 to 8 weeks of treatment is often needed before significant improvement is achieved

Question 33

Who is the best candidate for isotretinoin (Accutane) therapy? a) a 17-year-old patient with pustular lesions and poor response to benzoyl peroxide b) a 20-year-old patient with cystic lesions who has tried various therapies with minimal effect c) a 14-year-old patient with open and closed comedones and family history of "ice pick" scars d) an 18-year-old patient with inflammatory lesions and improvement with tretinoin (Retin-A)

Answer 33

B - a 20-year-old patient with cystic lesions who has tried various therapies with minimal effect

Question 34

In a 22-year-old woman using isotretinoin (Accutane) therapy, the NP ensures follow-up to monitor for all the following tests except: a) hepatic enzymes b) triglyceride measurements c) pregnancy d) platelet count

Answer 34

D - platelet count

Question 35

Leonard is an 18-year-old man who has been taking isotretinoin (Accutane) for the treatment of acne for the past 2 months. Which of the following is the most important question for the clinician to ask at his follow up office visit? a) "Are you having any problems remembering to take your medication?" b) "Have you noticed any dry skin around your mouth since you started using Accutane?" c) "Do you notice any improvement in your skin?" d) "Have you noticed any recent changes in your mood?"

Answer 35

D - "Have you noticed any recent changes in your mood?"

Question 36

In a 13-year-old female patient with mild acne and who experiences an inadequate response to benzoyl peroxide treatment, an appropriate treatment option would be to: a) add a topical retinoid b) add an oral antibiotic c) consider isotretinoin d) consider hormonal therapy

Answer 36

B - add an oral antibiotic