Lack of effect of P-glycoprotein inhibition on renal clearance of dicloxacillin in patients with cystic fibrosis.

Study Objective: To determine whether upregulation of P-glycoprotein is responsible for the enhanced renal clearance of dicloxacillin in patients with cystic fibrosis.

Design: Single-center, prospective, open-label, randomized, three-part crossover pharmacokinetic study.

Setting: General clinical research center.

Probenecid, but not cystic fibrosis, alters the total and renal clearance of fexofenadine.

This study aims to evaluate renal P-glycoprotein (P-gp) activity in patients with cystic fibrosis. P-gp efflux activity in peripheral T cells was measured by flow cytometry in 10 cystic fibrosis and 15 healthy volunteers. Eight cystic fibrosis patients and 8 healthy volunteers were recruited into a crossover pharmacokinetic study in which participants received 180 mg fexofenadine with or without 1 g probenecid twice a day.

Absolute bioavailability and intracellular pharmacokinetics of azithromycin in patients with cystic fibrosis.

Chronic pulmonary infections with Pseudomonas aeruginosa are the primary cause of morbidity and mortality in patients with cystic fibrosis (CF). The macrolide antibiotics exhibit immunomodulatory and antivirulence activity. Clinical trials with azithromycin in CF have demonstrated significant improvements in pulmonary function and decreased hospitalizations.

Pharmacokinetics of Ibuprofen in children with cystic fibrosis.

An exaggerated inflammatory response is responsible for the decline of lung function in patients with cystic fibrosis (CF). Ibuprofen is a potent anti-inflammatory agent that demonstrates inhibition of neutrophil activity in vitro at concentrations between 50 and 100 mg/L, whereas lower concentrations result in an increase in inflammatory mediators. Significant decline in the rate of deterioration of pulmonary function and increased nutritional status were observed in children with CF who were administered long-term high-dosage ibuprofen therapy.