Scalp Psoriasis (cont.)

Rarely, it may be of benefit to inject triamcinolone acetonide directly into psoriatic plaques. Aside from the pain involved, the benefit only lasts about six weeks at best. Ultraviolet light in wavelengths near 313nm (narrow band UVB) is effective in psoriasis. The hair, however, can pose a barrier to effective administration unless it is removed or sparse. The excimer laser puts out laser light in these UV wavelengths also and can be of benefit if the amount of scalp involvement is limited.

If the scalp is involved as part of severe psoriasis deemed too extensive to be treated practically with topical medications, then medications delivered orally or through the skin may be necessary. All these medications comprise more risk when compared to topical medication. They include oral drugs like methotrexate (Rheumatrex, Trexall), cyclosporine (Sandimmune), acitretin (Soriatane), and some of the so-called biological drugs that are administered by infusion into a vein (infliximab [Remicade]) or by injection into the deeper layers of the skin like etanercept (Enbrel), adalimumab (Humira), ustekinumab (Stelara). Regular laboratory work is required to monitor for the toxicities associated with these systemic therapies.

Source: MedicineNet.com
http://www.medicinenet.com/scalp_psoriasis/article.htm