EBASTINE

Introduction

Ebastine is a piperidine derivative,is non sedating anti-histamine. Eastine is 4-dipheylmethoxy-1-(3-(4-terbutylbezoyl)
propyl),long-acting, second generation, selective H1-receptor inverse agonist.

Ebastine has a chemical strcture which is different from other second generation anti-histamine. After over 18 years of use in more than 80 countries around the globe, the efficacy and safety of ebastine has been extensively demonstrated.

Small studies have found beneficial effect in patients suffering from allergic dermatitis, cold urticaria, atopic asthma, Mosquito bite, and the common cold.

Pharmacological action

Ebastine is a long-acting and selective H1-histamine receptor antagonist. After repeated administration, inhibition of peripheral receptor remains at a constant level. Ebastine is rapidly absorbed and undergoes extensive first pass metabolism following oral administration. Ebastine is almost tottly converted to the pharmacologically active acid metabolite, carebastine. Peak plasma level of the metabolites(80ng to 100ng/ml) occr within two to four hours. Food incresese the plasma level of carebastine 1.5-2.0 fold. Half life is in between 15-19 hours. Ebastine and carebastine are highly protein bound(>95%).

Indication

Allergic rhinitis ( Seasonal and perennial) whether or not associated with allergic conjunctivitis. Idiopathic chronic urticaria.

Adverse effect

Headache, dry mouth and drowsiness. Rearely abdominal pain, dyspepsia, asthenia, pharyngitis, epitaxis, sinusitis, nausea and insomnia may occurs.

Contra-indication

Patients with a known hypersensitivity to ebastine or any of it’s ingredients . The safety of eastine during pregnancy and lactation has not been established.

Interaction

Ebastine does not interact with the kinetics of the theophylline, warfarin, cimetidine, diazepam and alcohol. The sedation effect of alcohol and diazepam may be enhanced.

Interaction with ketoconazole or erythromycin increases QTc level.

Dose

Allergic rhinitis : 10 mg to 20 mg daily.
Urticaria : 10 mg daily.

In patients with mild to moderate hepatic impairment should not take more than 10 mg per day.

Warning

Exercise caution when using ebastine in patients with known long QT syndrome, hypokalamia, treatment with any drug known to produce an increases in QT intervals or inhibits CYP3A4 enzyme system such as azole antifungals and microlide antibiotics, moderate to severe hepatic and or renal impairement.