Wednesday, March 09, 2011
Pityriasis rosea (PR) is a papulosquamous eruption of unknown
etiology. A viral pathogenesis has been proposed but is unproven.
It resolves spontaneously, thus treatment usually is not required.
Atypical cases may be caused by medications (PR-like drug
eruption), especially gold. Secondary syphilis must be
- As the condition is self-limited, the option of simple
emollient therapy and antihistamines such as hydroxyzine
10-50 mg nightly should be considered.
- Mid- to high-potency topical steroids applied twice daily may
- For severe cases, erythromycin 250 mg 4 times daily for 7-10
days may lead to improvement.
- Narrowband UVB phototherapy can be effective for pruritus
caused by PR.
For severe cases of PR with pruritus uncontrolled by the above
approaches, consider prednisone 1 mg/kg/day for 5-7 days, and taper
over 2-3 weeks.
Failing to diagnose secondary syphilis or a drug eruption
resembling PR is of most concern.