RESUMEN
OBJECTIVE To determine the pharmacokinetics of a single dose of meloxicam after IM and oral administration to healthy lesser flamingos (Phoeniconaias minor) by use of a population approach. ANIMALS 16 healthy captive lesser flamingos between 1 and 4 years of age. PROCEDURES A single dose of meloxicam (0.5 mg/kg) was administered IM to each bird, and blood samples were collected from birds at 3 (n = 13 birds), 2 (2), or 1 (1) selected point between 0 and 13 hours after administration, with samples collected from birds at each point. After a 15-day washout period, the same dose of meloxicam was administered PO via a red rubber tube and blood samples were collected as described for IM administration. Pharmacokinetic values were determined from plasma concentrations measured by high-performance liquid chromatography. RESULTS Plasma drug concentrations after IM administration of meloxicam reached a mean ± SD maximum value of 6.01 ± 3.38 µg/mL. Mean area under the concentration-versus-time curve was 17.78 ± 2.79 µgâ¢h/mL, and mean elimination half-life was 1.93 ± 0.32 hours. Plasma concentrations after oral administration reached a mean maximum value of 1.79 ± 0.33 µg/mL. Mean area under the curve was 22.16 ± 7.17 µgâ¢h/mL, and mean elimination half-life was 6.05 ± 3.53 hours. CONCLUSIONS AND CLINICAL RELEVANCE In lesser flamingos, oral administration of meloxicam resulted in higher bioavailability and a longer elimination half-life than did IM administration, but the maximum plasma concentration was low and may be insufficient to provide analgesia in flamingos. Conversely, IM administration achieved the desired plasma concentration but would require more frequent administration.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacocinética , Aves/metabolismo , Tiazinas/farmacocinética , Tiazoles/farmacocinética , Administración Oral , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Área Bajo la Curva , Disponibilidad Biológica , Aves/sangre , Femenino , Semivida , Inyecciones Intravenosas/veterinaria , Masculino , Meloxicam , Tiazinas/administración & dosificación , Tiazoles/administración & dosificaciónRESUMEN
BACKGROUND/AIMS: Several recent studies revealed an accumulation of ceramide in bronchial, tracheal and intestinal epithelial cells of mice and patients with cystic fibrosis (CF). Normalization of ceramide concentrations in lungs of CF mice employing the functional acid sphingomyelinase inhibitor amitriptyline also normalized mucociliary clearance, chronic inflammation and infection susceptibility to pulmonary P. aeruginosa in these mice. METHODS: To test for a beneficial effect of amitriptyline in vivo, we performed a phase IIb randomised, double-blind, placebo-controlled study. Twenty-one CF patients were treated with 25 mg/d amitriptyline twice daily for 28 days. The placebo consisted of 19 patients and was also treated twice per day. The primary endpoint was the change in lung function in the intention-to-treat (ITT) population. Secondary endpoints were ceramide levels in epithelial cells and safety. RESULTS: After treatment, forced expiratory volume in 1 sec predicted (FEV1) increased 6.3 ± 11.5% (p=0.08) in the ITT population (36 of 40 CF patients) and 8.5 ± 10% (p=0.013) in the per protocol (PP) population (29 of 40 patients). Ceramide levels decreased in nasal epithelial cells after amitriptyline treatment. Amitriptyline had no severe and only mild and mostly transient adverse effects, i.e. xerostomia and tiredness. CONCLUSION: Amitriptyline is safe in CF-patients, increases FEV1 and reduces ceramide in lung cells of CF patients.