Efficacy of leukotriene receptor antagonist with an anti-H1 receptor antagonist for treatment of chronic idiopathic urticaria.

BACKGROUND: Chronic idiopathic urticaria (CIU) is often difficult to treat. Although histamine-releasing activity is detectable for up to 50% of CIU patients, antihistamine therapy provides only a limited response.

OBJECTIVE: This study aimed to assess the clinical efficacy of combined leukotriene receptor antagonist (LRA) and H1 antihistamine, H1 and H2 antihistamine, and two H1 antihistamines as a synergistic therapeutic regimen for treating CIU compared with a matched placebo modality.

METHODS: A total of 120 newly diagnosed adult patients were evaluated. Patients were single blinded and randomly assigned to one of four medication groups that received the following regimens for 4 weeks: Group A, combination of sedating H1 antihistamine and non-sedating H1 antihistamine; Group B, combination of H1 antihistamine and H2 antihistamine; Group C, combination of H1 antihistamine and LRA; and Group D, matched placebo medication. The primary measure of treatment efficacy was the daily urticaria activity score (UAS) of 'wheal and itch'. A positive therapeutic response was defined as a reduction to < 25% of baseline weekly UAS, while a relapse was a return to > 75% of baseline weekly UAS.

RESULTS: In all, 107 patients completed the trial medication. At the end of 4 weeks, the UAS score as a response to treatment was 23.3% for Group A, 63.3% for Group B, 53.3% for Group C, and no real change for the placebo treatment group.

CONCLUSIONS: The combination of LRA and H1 receptor antagonist is promising for CIU treatment and is reasonably well tolerated by patients. The combination of H1- and H2-receptor antagonists provided the greatest treatment efficacy by the measures used in this small study.