Allergic contact dermatitis caused by calcipotriol.

When topical treatment with calcipotriol fails to improve, or even worsens, existing skin lesions, contact allergy should be suspected. A patch test concentration of 2 µg/ml in isopropyl alcohol seems to be the most suitable. According to the literature, patients sensitized to calcipotriol may tolerate topical therapy with other vitamin D3 analogues, particularly tacalcitol.