Search results for "PHARMACOKINETICS"
showing 10 items of 458 documents
Comparing metoclopramide electrotransport kinetics in vitro and in vivo.
2010
The purpose of this work was to investigate the transdermal iontophoretic delivery of metoclopramide and to determine (i) the dependence of electrotransport on current density and drug concentration, (ii) the relative contributions of electromigration and electroosmosis and (iii) the feasibility of administering therapeutic amounts of drug, using a drug-sparing iontophoretic configuration. Iontophoretic delivery of metoclopramide (MCL) across dermatomed porcine ear skin was investigated in vitro as a function of concentration (10, 20, 40, 80 and 100mM) and current density (0.1, 0.2 and 0.3mAcm(-2)) using vertical flow-through diffusion cells. In vivo studies were performed in Wistar rats (4…
Biowaiver monograph for immediate-release solid oral dosage forms: fluconazole.
2014
Literature data pertaining to the decision to allow a waiver of in vivo bioequivalence (BE) testing requirements for the approval of immediate release (IR) solid oral dosage forms containing fluconazole as the only active pharmaceutical ingredient (API) are reviewed. The decision is based on solubility, dissolution, permeability, therapeutic index, pharmacokinetic parameters, pharmacodynamic properties, and other relevant data. BE/bioavailability (BA) problems and drug-excipients interaction data were also reviewed and taken into consideration. According to the biopharmaceutics classification system (BCS), fluconazole in polymorphic forms II and III is a BCS class I drug and has a wide ther…
Pharmacokinetic evaluation of oral fenofibrate nanosuspensions and SLN in comparison to conventional suspensions of micronized drug.
2007
An increasing number of newly developed drugs show bioavailability problems due to poor water solubility. Formulating the drugs as nanosuspensions may help to overcome these problems by increasing saturation solubility and dissolution velocity. In the present study the bioavailability of the poorly soluble fenofibrate following oral administration was investigated in rats. Four formulations were tested: a nanosuspension type DissoCube(R), one solid lipid nanoparticle (SLN) preparation and two suspensions of micronized fenofibrate as reference formulations, one suspension in sirupus simplex and a second in a solution of hydroxyethy-cellulose in physiological saline. Both colloidal drug deliv…
Polypharmacy and the risk of drug-drug interactions and potentially inappropriate medications in hospital psychiatry.
2021
PURPOSE The aim of this study was to analyze the epidemiology of polypharmacy in hospital psychiatry. Another aim was to investigate predictors of the number of drugs taken and the associated risks of drug-drug interactions and potentially inappropriate medications in the elderly. METHODS Daily prescription data were obtained from a pharmacovigilance project sponsored by the Innovations Funds of the German Federal Joint Committee. RESULTS The study included 47 071 inpatient hospital cases from eight different study centers. The mean number of different drugs during the entire stay was 6.1 (psychotropic drugs = 2.7; others = 3.4). The mean number of drugs per day was 3.8 (psychotropic drugs …
Biowaiver Monographs for Immediate-Release Solid Oral Dosage Forms: Nifedipine
2015
Literature data relevant to the biopharmaceutical properties of the active pharmaceutical ingredient (API) nifedipine are reviewed to evaluate whether a waiver of in vivo bioequivalence (BE) testing of immediate-release (IR) dosage forms formulated as tablets and soft gelatin capsules is warranted. Nifedipine's solubility and permeability, its therapeutic use and index, pharmacokinetics, food drug interactions, and any reported BE/bioavailability problems were all taken into consideration. Solubility and BA data indicate conclusively that nifedipine is a class II substance of biopharmaceutics classification system (BCS) and that the formulation of drug product plays a key role on the dissol…
Response to Agomelatine Treatment is Independent of Smoking Status and Dosage: Results From the AGOPSYCH Study.
2018
Abstract Introduction Cigarette smoking influences response to antidepressant treatment. It accelerates the metabolism of several cytochrome P450 (CYP) subtypes, including CYP1A2, and therefore bears the risk of pharmacokinetic interactions with psychotropic drugs using that pathway. Agomelatine is a substrate of CYP1A2; the association between nicotine use and agomelatine dosage, however, has never been studied before. Methods Smoking habits were correlated with agomelatine doses and treatment outcomes in a sample of 27 patients with lifetime diagnoses within the schizophrenia spectrum who received agomelatine treatment in addition to their stable antipsychotic treatment regimen because of…
A multilevel object-oriented modelling methodology for physiologically-based pharmacokinetics (PBPK): Evaluation with a semi-mechanistic pharmacokine…
2019
Abstract Background and objective The aims of this study are (i) to assess the predictive reliability of the physiologically based software PhysPK versus the well-known population approach software NONMEM for the cited semi-mechanistic PK model, (ii) to determine whether these modelling approaches are interchangeable and (iii) to compare acausal with causal modelling approaches in the framework of semi-mechanistic PK models. Methods A semi-mechanistic model was proposed, which assumed oral administration of a solid dosage form with a peripheral compartment and two active metabolites. The model incorporates intestinal transit, dissolution limited by solubility, variable efflux transporter ex…
Biopartitioning micellar separation methods: modelling drug absorption
2003
The search for new pharmacologically active compounds in drug discovery programmes often neglects biopharmaceutical properties as drug absorption. As a result, poor biopharmaceutical characteristics constitute a major reason for the low success rate for candidates in clinical development. Since the cost of drug development is many times larger than the cost of drug discovery, predictive methodologies aiding the selection of bioavailable drug candidates are of profound significance. This paper has been focussed on recent developments and applications of chromatographic systems, particularly those systems based on amphiphilic structures, in the frame of alternative approaches for estimating t…
Ketamine in acute phase of severe traumatic brain injury “an old drug for new uses?”
2021
AbstractMaintaining an adequate level of sedation and analgesia plays a key role in the management of traumatic brain injury (TBI). To date, it is unclear which drug or combination of drugs is most effective in achieving these goals. Ketamine is an agent with attractive pharmacological and pharmacokinetics characteristics. Current evidence shows that ketamine does not increase and may instead decrease intracranial pressure, and its safety profile makes it a reliable tool in the prehospital environment. In this point of view, we discuss different aspects of the use of ketamine in the acute phase of TBI, with its potential benefits and pitfalls.
Isosorbide dinitrate: pharmacokinetics after intravenous administration.
1982
Isosorbide dinitrate (ISDN) is an important organic nitrate found therapeutically useful in its sublingual and oral forms in various cardiovascular diseases such as angina pectoris (1) and congestive heart failure (2). Recently Distante et al. (3) showed that an intravenous infusion of this drug, at 0.021–0.083 mg/min is also effective in managing unstable angina. The availability of an intravenous dosage form of ISDN not only affords the opportunity to characterize the pharmacokinetics of this drug after this particular mode of therapy, but also gives the possibility of assessing the bio-availability of this drug after other (e.g., oral) routes of administration in patients. This latter po…