The effect of flurbiprofen, a potent cyclo-oxygenase inhibitor, on histamine and methacholine reactivity was assessed in seven atopic subjects with asthma. Flurbiprofen 150 mg daily for three days displaced the histamine-FEV1 concentration-response curve to the right by 1.5 doubling doses, whereas no effect was observed on the response to methacholine. Subsequently the effects of flurbiprofen a...

P-glycoprotein (P-gp) plays an important role in determining net brain uptake of fexofenadine. Initial in vivo experiments with 24-h subcutaneous osmotic minipump administration demonstrated that fexofenadine brain penetration was 48-fold higher in mdr1a(-/-) mice than in mdr1a(+/+) mice. In contrast, the P-gp efflux ratio at the blood-brain barrier (BBB) for fexofenadine was only approximately...

The substrate structure-activity relationships described for the major human drug-metabolizing cytochrome P450 (P450 or CYP) enzymes suggest that the H1 receptor antagonist terfenadine could interact with CYP2D6 either as a substrate or as an inhibitor, in addition to its known ability to act as a substrate for CYP3A4. Based on this substrate structure-activity relationship, computer modeling s...

We have investigated the protective effect of oral terfenadine, a H1 antagonist, on the dermal and pulmonary response, and changes of circulating WBCs to injected and inhaled platelet activating factor. Nine men with mild asthma participated in a double-blind, crossover study using terfenadine, 120 mg, or placebo. Three hours after administration of study drug, pulmonary function was measured, ...

Ninety patients participated in a randomised, double blind, placebo controlled comparison of terfenadine with astemizole in the treatment of hay fever. They entered the trial as a cohort before the grass pollen season and recorded daily their symptoms of itching eyes, sneezing, running nose, and blocked nose on visual analogue scales in diary cards. Over the eight weeks of the trial astemizole ...

OBJECTIVE To evaluate whether 1 year of continuous treatment with intranasal fluticasone propionate would lead to atrophy in the nasal mucosa compared with an active control, oral terfenadine. DESIGN Prospective, randomized, multicenter, open-label, parallel-group study. SETTING Two tertiary care academic institutions. PATIENTS Seventy-five subjects older than 18 years with perennial alle...

Ten patients with stable chronic asthma completed a randomized double-blind placebo controlled crossover study examining the effect of 120mg terfenadine twice daily for 4 weeks on bronchial responsiveness. Bronchial responsiveness was measured by methacholine inhalation tests performed by the tidal breathing technique at 0, 2 and 4 weeks of active and placebo treatment periods separated by a on...

OBJECTIVE To develop topical gel preparations of astemizole and terfenadine and to investigate the actions of the gels on the healing of incision and excision wounds in male albino rats. MATERIALS AND METHODS Gels containing 1% astemizole, with varying concentrations of carbopol 934 (polymer), were prepared. Similarly, 1% terfenadine gels were made. The formulations were evaluated for release...

Ketoconazole, a widely used fungicide in patients, has been associated with Q-T prolongation and torsade de pointes when co-administered with terfenadine (Seldane). Both compounds use the same cytochrome-P450 metabolic pathway, resulting in an increase in plasma concentration of terfenadine. We previously showed that terfenadine blocked HERG (Human Ether-a-Gogo Related Gene), an important compo...

BACKGROUND/AIMS The antihistaminic drug Terfenadine may trigger apoptosis of tumor cells, an effect unrelated to its effect on histamine receptors. Similar to apoptosis of nucleated cells, erythrocytes may enter eryptosis, the suicidal death of erythrocytes characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Signaling tr...