Bilastine for allergic rhinoconjunctivitis, urticaria
- First published 1 September 2022
- Aust Prescr 2022;45:179
- 4 October 2022
- DOI: 10.18773/austprescr.2022.057
Approved indication: allergic rhinoconjunctivitis, urticaria
20 mg tablets
Bilastine is a long-acting antihistamine that has been available in Europe for more than a decade. It is an antagonist of peripheral H1 receptors, has no effect on muscarinic receptors and probably has limited transit across the blood–brain barrier. Bilastine therefore adds to the choice of less-sedating antihistamines for allergic conditions.1
Tablets of bilastine should not be taken with food or fruit juice as its bioavailability may be reduced. There is minimal metabolism with most of the drug being excreted unchanged, mainly in the faeces. No dose adjustment is recommended for patients with hepatic or renal impairment. The mean elimination half-life is 14.5 hours so only one dose a day is needed.
The approval of bilastine includes both seasonal and perennial allergic rhinitis. There have been several trials of bilastine for allergic rhinitis and five of them were included in a systematic review. These were placebo-controlled trials, but four of them also included other antihistamines for comparison. A total of 3329 patients participated.2
Bilastine reduced the total symptom score more than a placebo did. It had favourable effects on nasal and non-nasal symptoms. These effects were similar to those of cetirizine, desloratadine and fexofenadine.2
The main double-blind trial of bilastine in urticaria involved 525 patients with chronic idiopathic urticaria. They were randomised to take a daily dose of bilastine 20 mg, levocetirizine 5 mg or placebo for 28 days. Both active treatments reduced pruritus and the number and size of wheals.3
Most of the efficacy trials were short, but there are now several years of experience with the drug overseas. An open-label extension of a trial in perennial allergic rhinitis followed 513 patients for a year and found bilastine was well tolerated.4 Common symptoms include headache, dizziness and abdominal pain, but their incidence is similar to that seen with other antihistamines and placebo. Somnolence can occur, but in the systematic review there was no difference from placebo.2 Bilastine has been reported not to enhance the effects of lorazepam or add to the effects of alcohol on psychomotor performance. Bilastine does not prolong the QT interval on the ECG. While data in pregnancy are limited, animal studies suggest only very high doses affect embryofetal development. Bilastine does enter animal breast milk. The drug is not yet approved for children under 12 years old.
There seems to be no difference in efficacy between bilastine and other antihistamines. It may cause less somnolence than cetirizine, but the incidence is similar to that seen with desloratadine and fexofenadine.2
At the time the comment was prepared, information about this drug was available on the websites of the Food and Drug Administration in the USA, the European Medicines Agency and the Therapeutic Goods Administration.
Some of the views expressed in the following notes on newly approved products should be regarded as preliminary, as there may be limited published data at the time of publication, and little experience in Australia of their safety or efficacy. However, the Editorial Executive Committee believes that comments made in good faith at an early stage may still be of value. Before new drugs are prescribed, the Committee believes it is important that more detailed information is obtained from the manufacturer’s approved product information, a drug information centre or some other appropriate source.