Lippincott Chapter 34: Drugs for Dermatologic Disorders

Question 1

34.1 Which of the following is correct regarding the use of
isotretinoin in the treatment of acne?
A. Isotretinoin is given intravenously in the treatment
of acne.
B. Isotretinoin acts primarily on the membrane
receptors.
C. If given in high dosages, isotretinoin can indirectly
increase the concentration of Propionibacterium
acnes bacteria.
D. Isotretinoin activates prostaglandin E2
and
collagenase, which causes the adverse effect of
inflammation.
E. Isotretinoin is contraindicated in pregnancy due to
its high risk of birth defects.

Answer 1

E. Isotretinoin is contraindicated in pregnancy due to
its high risk of birth defects.

Question 2

34.2 A 3-year-old boy has contracted scabies from his
playmate at the daycare center. Which of the following
would be the most appropriate treatment?
A. Azelaic acid.
B. Mupirocin.
C. Permethrin.
D. Triple antibiotic ointment.

Answer 2

Correct answer = C. Permethrin is a topical scabicide that is
preferred due to its lower risk of neurotoxicity. Azelaic acid is
a topical treatment for acne. Mupirocin and triple antibiotic
ointment are used for the treatment of bacterial infections
and would not be appropriate for scabies.

Question 3

34.3 Which of the following drugs is taken orally before
using UVA radiation in the treatment of severe cases
of psoriasis?
A. Methoxsalen.
B. Hydroquinone.
C. Finasteride.
D. Minoxidil.
E. Tazarotene.

Answer 3

Correct answer = A. In severe cases of psoriasis, methox-
salen is taken orally followed by UVA phototherapy. Other
drugs are not options for treating severe cases of psoria-
sis. Hydroquinone is a topical depigmenting agent used for
the treatment of photoaging. Finasteride is an oral drug for
the treatment of alopecia, and minoxidil is a topical drug
for alopecia. Tazarotene is a topical agent indicated for the
treatment of acne or psoriasis.

Question 4

34.4 Which of the following is correct regarding trichogenic
agents?
A. Minoxidil is known to decrease the microcirculation
surrounding the follicle, thus decreasing cutaneous
blood flow.
B. A frequent adverse effect of topical minoxidil is
orthostatic hypotension.
C. Finasteride inhibits the 5-α reductase enzyme that
controls the production of DHT from testosterone.
D. An adverse effect associated with finasteride is
increased libido.
E. Only 6 months of finasteride is necessary for a
lifelong benefit.

Answer 4

Correct answer = C. Androgenic alopecia is associated with
DHT concentrations, and finasteride is known to inhibit the
5-α reductase enzyme required for the formation of DHT
from testosterone. Continuous use of finasteride is needed
to maintain therapeutic benefit for alopecia. Finasteride can
decrease libido.