**4.2.1 Calcipotriene/calcipotriol**

These are vitamin D 3 derivatives used for chronic, moderately/severe Psoriasis of the scalp. The 0.005% solution is applied to the affected area and rubbed gently onto the scalp twice a day. Response to therapy takes about 8 weeks. It is not recommended in patients with acute psoriatic eruptions on the scalp, those with hypercalcemia or hypervitaminosis D. The main side effects are burning, itching, irritation and dryness. Irritation tends to decrease with time. Clearance has been observed even with 8 weeks of once a day treatment in up to 60% of patients.
