FRIDAY, Dec. 2 (HealthDay News) -- Topical treatment with moisturizers and emollients such as petroleum jelly should be the first line of therapy for treating psoriasis in pregnant and breast-feeding women, according to new recommendations from the National Psoriasis Foundation Medical Board based in Portland, Ore.

These products should be tried first because they cause no known adverse effects.

Psoriasis, a chronic skin disease, affects as many as 7.5 million Americans. It usually appears as red, scaly patches that may itch and bleed.

"Treating psoriasis in women who are pregnant or breast-feeding presents special challenges due to the side effects of certain medications and the ethical concerns of placing this patient population in clinical trials," Dr. Mark Lebwohl, chair of the National Psoriasis Foundation Medical Board, said in a foundation news release. "It's important for women to work with their doctor to determine what treatment is appropriate for them during pregnancy and to consider the precautions for each."

After trying moisturizers and emollients, low to moderate doses of topical steroids may be used, followed by high-potency topical steroids only as needed in the second and third trimesters of pregnancy, the board said.

For pregnant women, narrowband ultraviolet B (UVB) light therapy should be the second-line treatment. If narrowband UVB is not available, broadband UVB may be used.

The board also said that a class of immune system-suppressing drugs called TNF inhibitors and the immunosuppressant drug cyclosporine may be used with caution in the second and third trimesters of pregnancy. Certain strategies can be used to minimize risk and exposure.

Women are advised not to breast-feed while taking medications because there is a lack of research on potential effects.

More information

The American Academy of Family Physicians has more about psoriasis.