Terfenadine A Review of its Pharmacodynamic Properties and Therapeutic Efficacy

Abstract

Terfenadine is a selective H1-histamine receptor antagonist. The lack of significant terfenadine penetration into the CNS is probably responsible for its lack of CNS effects. Terfenadine neither impairs psychomotor performance nor adversely affects subjective feelings, nor enhances the depressant effects of concomitantly administered alcohol or benzodiazepines. In controlled studies, the incidence of sedation due to terfenadine was comparable with that of placebo and significantly less than that with conventional antihistamines. Clinical studies have shown terfenadine to be comparable in efficacy with other antihistamines while being superior to placebo in alleviating the symptoms of seasonal allergic rhinitis. Additionally, there is good evidence that it is similarly as effective when used in the treatment of perennial rhinitis and histamine-mediated skin diseases. Thus, terfenadine offers a worthwhile improvement in side effect profile over 'traditional' antihistamines, and could well become an 'agent of choice' (along with other non-sedating antihistamines) in many patients in whom a histamine H1-receptor antagonist is indicated.

Evidence for a Regulatory Role for Histamine in Gastric Enterochromaffin-Like Cell Proliferation Induced by Hypergastrinemia

“…We have therefore investigated the effects of a specific, se lective histamine Hpreceptor antagonist, terfenadine [25], on the development of ECL cell hyperplasia elicited by the pharmacologically irreversible Hi-receptor antago nist, loxtidine. The results suggest that histamine, acting through an H| receptor, is involved in the genesis of gas tric ECL cell hyperplasia.…”

Treatment of bronchial asthma with terfenadine; a randomized controlled trial.

“…However, the high doses required to produce such effects were associated with pronounced somnolence, precluding their use in routine therapy. Newer antihistamines like terfenadine (Sorkin & Heel, 1985) enable the question of the value of H1-receptor blockade in asthma to be re-assessed since higher doses can be used without causing sedative side effects (Moser & Huther, 1978;Brandon & Weiner, 1980).…”

Hi̇droksi̇zi̇n Ve Terfenadi̇ni̇n Allerjen Ve Hi̇stami̇nle Yapi̇lan Deri̇ Testleri̇ne Etki̇leri̇

“…Baskılanma birinci haftada % 83.8 iken, ikinci haftada % 87.8 bulunmuştur.Yine bu çalışma-da antijenle testler yapılmamış ve ilaç kesildikten sonraki baskılanmanın ne kadar sürdüğü araştırılma-mıştır (18). Terfenadinin etkisinin 2 saat içinde baş-ladığı ve histaminle yapılan deri testlerinin %100'e varan oranlarda baskıladığı bazı çalışmalarda öne sürülmüştür (8,17). Fakat bu oranlarda baskılanma bizim çalışmamızda ve başka çalışmalarda görül-memiştir (1,4).…”