Delayed pressure urticaria - dapsone heading for first-line therapy?

BACKGROUND

Pressure urticaria as a subform of physical urticaria is rare and treatment is often difficult. Established therapeutic regimes include antihistamines (generally exceeding approved dosages in order to achieve a therapeutic benefit) or antihistamines combined with montelukast. Complete relief of symptoms is difficult.

PATIENTS AND METHODS

We used dapsone as an early therapeutic alternative in the event of treatment failure and established a standardized therapeutic regime at our clinic. We surveyed 31 patients retrospectively who had received dapsone between 2003-2009.

RESULTS

In 74 % of patients in whom symptoms persisted despite established therapies, the results of treatment with dapsone were good or very good. Longer-term pressure urticaria and the co-existence of a chronic spontaneous urticaria were associated with a smaller benefit (p<0.05). No significant effects were found related to age, gender, duration of therapy, side-effects, or Met-Hb elevation (a tendency toward a decreased benefit was associated with middle-age, male sex, shorter duration of therapy, observed side-effects, and Met-Hb elevation).

CONCLUSIONS

Therapy is well tolerated and results in a good therapeutic benefit which lasts after termination of therapy. With adequate monitoring, the use of dapsone in patients with pressure urticaria has such a good risk-benefit ratio that we support early treatment initiation.