In-patient treatment with calcipotriol versus dithranol in refractory psoriasis

Calcipotriol (50 μg/g) ointment recently became available for the treatment of psoriasis. Calcipotriol as been shown to be superior to home treatment with dithranol. The time-honoured regime of in-patient topical treatment with dithranol in paste or petrolatum for 24 hours is the gold standard of optimal efficacy of antipsoriatic therapy. This treatment regime is adopted in case of insufficient control of psoriasis by out-patient treatments. The aim of the present study was to challenge the position of in-patient dithranol treatment. A left-right comparative case-control study was designed in ten patients hospitalised with refractory psoriasis, comparing classical dithranol treatment and calcipotriol treatment. In contrast to what was expected, six of the ten patients showed a more pronounced improvement after two weeks at the calcipotriol treated sides. Irritation from calcipotriol was observed in four patients after one week and in two patients after two weeks treatment. At the dithranol treated sides three of the ten patients showed a better improvement. Four patients experienced irritation after one week and eight patients after two weeks. Irritation due to calcipotriol was not associated with an increased irritation due to dithranol, which implies that both treatments have a different mechanism of irritation. The present case-control study indicates that calcipotriol has challenged the untouchable superiority of classical in-patient treatment with dithranol. Further studies are indicated to improve compliance in out-patient calcipotriol treatment with cream formulations and once a day schedules.