Ebastine is a newer second-generation H1 blocker that gets converted quickly to the active metabolite carebastine, with a t½ of 10–14 hours. It is non-sedating and effective for nasal and skin allergies. It has been shown in animal studies to prolong Q-Tc interval, making it liable to arrhythmogenic potential and CYP3A4 interaction, however there are few actual reports.
Drug class
H1 antihistamine, 2nd generation
Available preparations
ebastine
- Tablet: 10 mg, 20 mg
- Syrup: 5 mg/5 ml
Dosage
- Adult: 10-20 mg once daily
- Children: 5 mg once daily (not recommended below 6-year age)
Common uses
- Seasonal and perennial allergic rhinitis
- Chronic idiopathic urticaria
Side effects
- Animal studies have found it to prolong Q-Tc interval
- Mild headedness
- Nausea
Pharmacological characteristics
- Onset of action: 1-3 hours
- Duration of action: 24-28 hours
- Half-life (t1/2): 10-14 hours
- Metabolized by CYP 3A4 to active metabolite carebastine, hence metabolism inhibited by CYP 3A4 inhibitors