EBASTINE IN CHRONIC SPONTANEOUS URTICARIA IN HIGHER DOSES

Sir,

Nonsedating antihistamines are recommended as first-line treatment for patients with urticaria. The current European Academy of Allergology and Clinical Immunology/Global Allergy and Asthma European Network/European Dermatology Forum (EAACI/GA²LEN/EDF) guidelines call for updosing of nonsedating antihistamines (up to four times the standard dose) in those urticaria patients who do not respond satisfactorily to the standard doses.[1] There are a few studies to assess the efficacy of such a recommendation.

Ebastine is a selective, long-acting, nonsedating, second-generation antihistamine. It has been reported to be safe and effective in the treatment of allergic rhinitis and chronic idiopathic urticaria.[2] Ebastine is a second-generation H₁-receptor antagonist with an oxypiperidine-based structure, whose active form is the metabolite carebastine. Ebastine is administered orally once daily and is indicated for the treatment of the symptoms of allergic rhinitis and chronic idiopathic urticaria.[3]

We tried ebastine in chronic spontaneous urticaria in higher doses. Thirty patients (16 females and 14 males, age group 20–60 years, mean age 30.2 years) with chronic spontaneous urticaria for at least 6 weeks and pruritus, weal score of more than two were enrolled after an informed written consent. The exclusion criteria included physical urticaria, urticarial vasculitis, pregnant or lactating women, gastritis, a history of sensitivity to aspirin or NSAIDs and a history of aggravation of symptoms by pressure. Routine investigations like complete blood count, blood sugar, thyroid-stimulating hormone (TSH), and urine examination were done to rule out infections before starting therapy. All 30 patients had chronic spontaneous urticaria of duration ranging from 3 months to 2 years (mean duration 15.8 months).

After a 1-day washout without treatment, we graded symptoms using the urticaria activity score (UAS). The UAS measures two symptoms-quantity of wheals and intensity of itching-each on a 0-3 scale each day. The UAS was recorded by each patient on daily basis, and obtained from patients weekly. The number of weals was scored from 0 to 3: 0, no weals; 1, less than 20 weals; 2, 20: 50 weals; 3, >50 weals almost covered or large confluent areas of weals. Severity of itch was scored as 0, none; 1, mild; 2, moderate; and 3, severe. One has to add each score together for both number of weals and the severity of itching on a given day for each the 7 days in a given week to get the weekly UAS. The possible weekly aggregate UAS thereby ranged from 0 to 42.[1] Sedation was graded from 0 to 3 (0, none; 1, mild; 2, moderate; and 3, severe). We recorded UAS at 0, 2, and 4 weeks to monitor urticaria.

All patients were started with ebastine 10 mg tablet at bedtime. Patients were reviewed on weekly intervals for four weeks. For symptomatic patients, the dose of ebastine was doubled to 20 mg of ebastine tablet at bedtime at the end of 1 week, and two tablets of ebastine 20 mg in two divided doses at the end of 2 weeks. Investigations revealed microcytic anemia in three patients and raised TSH in two patients. Average UAS was 4.6 at 0 weeks which came down to 2.2 at 1 week. Three patients were lost to follow up at the end of 1 week possibly due to poor response. At the end of 1 week, 10 patients out of 27 were symptomatic. We doubled the dose to 20 mg of ebastine at bedtime. At two weeks, UAS was 1.1. At the end of 2 weeks, two out of 10 patients were symptomatic whose dose was doubled to 20 mg of ebastine twice a day. At the end of 4 weeks, UAS came down to less than 1.

Sedation was recorded as 0, mild, or moderate or severe. One patient with 40 mg of ebastine complained of sedation, which was mild. Seventeen, eight, and two patients became symptom-free when administered 10, 20, and 40 mg ebastine, respectively.

We have reported updosing with levocetirizine to control chronic urticaria in Indian patients.[4]

A superior efficacy of 20 mg of ebastine is observed compared with 10 mg of ebastine and 10 mg of cetirizine on the skin wheal response 24 h after the last dose of a 6-day-long treatment. This study clearly proved ebastine to be an effective, truly once-daily antihistamine.[5] Study from Germany showed that 20 mg of ebastine is safe and effective in preventing the symptoms of dermographic urticaria. This study also found ebastine had no negative effective on cognitive performance or mood.[6] Ebastine at doses up to five times the recommended therapeutic dose did not cause clinically relevant changes in QTc interval.[7] In addition to the regular ebastine tablet, a fast-dissolving tablet (FDT) formulation, which disintegrates in the mouth without the aid of a drink, is also available.

Summarizing ebastine is safe and effective in higher doses to control chronic spontaneous urticaria.