Search results for "Biological availability"
showing 10 items of 182 documents
Atenolol interaction with aspirin, allopurinol, and ampicillin.
1983
Atenolol kinetics were investigated in six healthy subjects after 100 mg orally, as monotherapy a 6-day treatment began 48 hr later. After a therapy-free interval of 4 wk, the same subjects received the same dose of atenolol with 1 gm ampicillin, 500 mg aspirin, and with 300 mg allopurinol. Allopurinol and aspirin did not substantially alter the kinetics of atenolol. After a single oral dose of 100 mg atenolol combined with 1 gm ampicillin, the bioavailability of atenolol was reduced to 36 +/- 5% compared to 60 +/- 8% after monotherapy. During long-term treatment with atenolol and ampicillin the bioavailability of atenolol fell to 24% (P less than 0.01). Mean peak plasma levels were lowered…
Relationship between rheological properties, in vitro release and in vivo equivalency of topical formulations of diclofenac.
2019
Determination of bioequivalence remains a challenge in generic topical drug development. To support pharmacokinetic studies, strategies to demonstrate microstructure sameness of the products being compared include in vitro evaluations, such as the comparison of rheological properties, droplet size and in vitro release rates. Nevertheless, defining the appropriate acceptance range to consider equivalence between test and reference formulation is complex. To shed more light into this issue, in vitro release and rheological properties were compared to in vivo bioequivalence data (systemic blood measurements within a clinical trial) after topical application of a single dose. Test and reference…
Effects of a plant-based fatty acid supplement and a powdered fruit, vegetable and berry juice concentrate on omega-3-indices and serum micronutrient…
2020
The major aim of this controlled, randomised, open-labelled, parallel-grouped, clinical trial was to investigate whether supplementation with different dosages of omega-3 fatty acids (0.5 g/d and 1 g/d) from a plant-based fatty acid supplement affected omega-3-indices (O3I) in well-nourished, healthy people. In addition, the combined ingestion of the plant-based fatty acid supplement, together with an encapsulated fruit, vegetable and berry (FVB) juice powder concentrate, was applied in order to observe the absorption of certain micronutrients and to examine some aspects related to the safe consumption of the products. The data demonstrate that the intake of only 0.5 g/day of omega-3 fatty …
Pharmacokinetics and bioavailability of benperidol in schizophrenic patients after intravenous and two different kinds of oral application
1994
Pharmacokinetics and bioavailability of benperidol were determined in 13 schizophrenic patients after acute administration of 6 mg benperidol as an intravenous (i.v.) bolus injection, orally as liquid, and orally as tablets using a partially randomized cross-over design. Drug plasma levels were determined by high performance liquid chromatography with electrochemical detection and subjected to model independent pharmacokinetic analyses. After i.v. dosing the geometric means (mean-g) were 3.2 min for the distribution half-life, 5.80 h for the elimination half-life (t1/2 beta), 4.21 l/kg for the distribution volume, 7.50 h for the mean residence time (MRT), and 0.50 l/(h*kg) for the clearance…
Pharmacokinetics of triamterene after i.v. administration to man: determination of bioavailability.
1983
With a new formulation, which made intravenous infusion of triamterene (TA) possible, plasma levels and urinary excretion rates of TA and its main metabolite (OH-TA-ester) were measured in a randomized, cross-over trial in 6 healthy volunteers given triamterene 10 mg i.v. and 50 mg p.o. TA and OH-TA-ester were determined by densitometric measurement of native fluorescence after thin layer chromatography. Distribution volumes of the central compartment of TA and OH-TA-ester were 1.49 l/kg and 0.11 l/kg, respectively. Terminal half-lives were 255 min for TA and 188 min for OH-TA-ester after i.v. administration. For TA total plasma clearance was 4.5 l/min and renal plasma clearance 0.22 l/kg. …
The tomato sauce making process affects the bioaccessibility and bioavailability of tomato phenolics: A pharmacokinetic study
2013
Tomato sauce is the most commonly consumed processed tomato product worldwide, but very little is known about how the manufacturing process may affect the phenolic composition and bioavailability after consumption. In a prospective randomised, cross-over intervention study, we analysed the plasma and urinary levels of tomato phenolic compounds and their metabolites after acute consumption of raw tomatoes and tomato sauce, enriched or not with refined olive oil during production. Respectively, eleven and four phenolic metabolites were found in urine and plasma samples. The plasma concentration and urinary excretion of naringenin glucuronide were both significantly higher after the consumptio…
IVIVC for fenofibrate immediate release tablets using solubility and permeability as in vitro predictors for pharmacokinetics.
2010
The goal of this study was to investigate the in vitro-in vivo correlation (IVIVC) for fenofibrate immediate release (IR) tablet formulations based on MeltDose-technique. The in vitro determined drug solubility and permeability data were related to the C(max) values observed from two in vivo human studies. Solubility and permeation studies of fenofibrate were conducted in medium simulating the fasted state conditions in the upper jejunum, containing the surfactant compositions of the six formulations at different concentrations. The behavior of all surfactant compositions was characterized by surface tension, dynamic light scattering, and cryo-TEM. The obtained solubility and permeation dat…
Oral versus intravenous vinorelbine: clinical safety profile
2005
The availability of chemotherapeutic drugs administrable by oral route represents a step forward in the management of cancer patients. Among oral agents, vinorelbine is particularly interesting for its pharmacological characteristics and clinical efficacy. Oral vinorelbine is rapidly absorbed (1.5-3 hours) with an elimination half-life of approximately 40 hours. It shows a low level of binding to plasma proteins (13%), is highly bound to platelets (78%) and has a hepatic metabolism and an absolute bioavailability of 40% with a moderate and similar interpatient variability for the two forms. Food has no influence on the pharmacokinetic profile of oral vinorelbine even if nausea/vomiting is l…
Pharmacokinetics of Droloxifene and Its Metabolites in Breast Cancer Patients
1991
Pharmacokinetics and metabolism of droloxifene, a new antiestrogenic drug, have been investigated by single- and multiple-dose studies in postmenopausal patients with advanced breast cancer. Short terminal elimination half-life, low accumulation, and improved drug tolerability are the most striking features of this safe and effective new antiestrogen. Bioequivalence of film-coated tablet, tablet, and standard solution of droloxifene has been shown. The concentrations of droloxifene and its metabolites have been determined by a highly selective HPLC method.
Properties of Resveratrol:In VitroandIn VivoStudies about Metabolism, Bioavailability, and Biological Effects in Animal Models and Humans
2015
Plants containing resveratrol have been used effectively in traditional medicine for over 2000 years. It can be found in some plants, fruits, and derivatives, such as red wine. Therefore, it can be administered by either consuming these natural products or intaking nutraceutical pills. Resveratrol exhibits a wide range of beneficial properties, and this may be due to its molecular structure, which endow resveratrol with the ability to bind to many biomolecules. Among these properties its activity as an anticancer agent, a platelet antiaggregation agent, and an antioxidant, as well as its antiaging, antifrailty, anti-inflammatory, antiallergenic, and so forth activities, is worth highlightin…