Hydroxychloroquine Efficacy in Chronic Urticaria

This study is for those people with difficult to treat hives. We are investigating whether or not a different medication, hydroxychloroquine, works to treat a certain type of hives. Hydrochloroquine is currently approved by the Food and Drug Administration (FDA), for treating arthritis, therefore it is considered investigational in this study. Hypothesis: Hydroxychloroquine will prove to have an efficacious response in terms of Urticarial Symptoms, on patients with chronic urticaria.

Our research question is: Is hydroxychloroquine an efficacious medicine to use in patients with chronic urticaria? Answering this question should help allergists treat chronic urticaria with a more evidence based approach. To date there has one been one prospective trial evaluating hydroxychloroquine in hives, and although it showed a trend towards efficacy (0.05<p<0.10), it was not statistically significant. There have been case series, and anecdotal reports which seem to demonstrate efficacy of chloroquine in chronic urticaria. Because of these reports hydroxychloroquine is often the first medication used in patients with chronic hives that are refractory to standard therapy of antihistamines. We believe an evidence based answer to this question will be an important step towards improved treatment of this disease. We plan to ascertain the efficacy of hydroxychloroquine by completing a randomized double blinded placebo controlled study of treatment in patients with chronic urticaria. We will be measuring an Urticarial Score to evaluate hive symptoms. We will be measuring them at baseline, and at the end of the study to note change in drug vs placebo.

Inclusion Criteria: Inclusion: Age >18, Age<65 Chronic Urticaria refractory to treatment with standard anti-histamines Minimum Urticaria Score Exclusion Criteria: Exclusion: Pregnancy Vasculitis Trigger Induced Urticaria Food intolerance Malignancy Kidney or liver dysfunction Systemic diseases Hypersensitivity to hydroxychloroquine

Reeves GE, Boyle MJ, Bonfield J, Dobson P, Loewenthal M. Impact of hydroxychloroquine therapy on chronic urticaria: chronic autoimmune urticaria study and evaluation. Intern Med J. 2004 Apr;34(4):182-6. doi: 10.1111/j.1444-0903.2004.00532.x.