Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Inhibition of soluble catechol-O-methyltransferase and single-dose pharmacokinetics after oral and intravenous administration of entacapone (1994)
    Springer
    European journal of clinical pharmacology 46 (1994), S. 151-157 
    Details
    ISSN: 1432-1041
    Keywords: Entacapone ; catechol-O-methyltransferase ; pharmacokinetics ; healthy volunteers ; adverse effects ; metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Abstract The inhibition of soluble catechol-O-methyltransferase (S-COMT) in red blood cells (RBCs) by entacapone, and the pharmacokinetics of entacapone after single oral (5–800 mg) and IV (25 mg) doses have been examined in an open study in 12 healthy young male volunteers. Oral entacapone dose-dependently decreased the activity of S-COMT in RBCs with a maximum inhibition of 82% after the highest dose (800 mg). The inhibition of S-COMT in RBCs was reversible and the activity recovered within 4–8 h. Entacapone showed linear pharmacokinetics over the dose range studied: Cmax and AUC were correlated with the dose of the drug. Oral absorption of entacapone was fast, with a tmax ranging from 0.4 to 0.9 h, depending on the dose. Systemic availability of entacapone varied between 30 and 46%. Entacapone was rapidly eliminated by metabolism with a half-life of 0.27–0.30 h after oral doses of 5 to 50 mg. After doses from 100 to 800 mg the disposition was best described by two phases with a t1/2α of 0.27–0.37 h and t1/2β of 1.59–3.44 h. Over the dose range studied, the single oral and IV doses of entacapone were well tolerated. No haematological, biochemical or haemodynamic adverse effects were seen. The results show that entacapone is an orally effective and reversible COMT inhibitor in man and has simple, linear pharmacokinetics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00199880
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of chlormethiazole in healthy volunteers and patients with cirrhosis of the liver (1980)
    Springer
    European journal of clinical pharmacology 17 (1980), S. 275-284 
    Details
    ISSN: 1432-1041
    Keywords: chlormethiazole ; cirrhosis of the liver ; antipyrine ; protein binding ; pharmacokinetics ; healthy volunteers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The pharmacokinetics of chlormethiazole after oral and intravenous administration was studied in six healthy volunteers and eight patients with alcoholic cirrhosis of the liver. Plasma concentration-time curve after the intravenous infusion could adequately be described by two- or three-compartment open models both in healthy volunteers and in the patients. Based on the areas under the plasma concentration-time curves, the systemic bioavailability of oral chlormethiazole was about ten times greater in the patients than in healthy controls. The elimination of chlormethiazole was relatively less retarded in the patients, as indicated by a decrease of about 30% in its plasma clearance. In the patients the plasma protein binding of chlormethiazole was decreased, but the volume of distribution and half-life of elimination were unchanged. The increase in bioavailability of chlormethiazole was associated with significant alteration in the serum levels of bilirubin, albumin, alkaline phosphatase, prothrombin-proconvertin activity (P + P) and elimination rate of antipyrine or14C-aminopyrine. The increased bioavailability of oral chlormethiazole was due to impaired first-pass metabolism in the cirrhotic liver. A considerable reduction in dose seems to be indicated if oral chlormethiazole is used in patients with advanced cirrhosis of the liver. A substantial fraction of dose, averaging 15%, was lost during the intravenous infusion, presumably due to adsorption to the infusion tubing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00625801
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of oral mexiletine in patients with acute myocardial infarction (1983)
    Springer
    European journal of clinical pharmacology 25 (1983), S. 773-777 
    Details
    ISSN: 1432-1041
    Keywords: mexiletine ; myocardial infarction ; pharmacokinetics ; gastro-intestinal absorption ; protein binding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary To study the effects of acute myocardial infarction on its pharmacokinetics a single oral dose of 400 mg mexiletine HCl was administered to seven patients. The study was performed within 24 h of the onset of pain (Study I) and was repeated 10–14 days later, during the recovery phase (Study II). Mexiletine in plasma and urine was quantified by a GLC method. The peak plasma concentrations of mexiletine were 0.65±0.05 (SEM) µg/ml and 1.08±0.11 µg/ml (p〈0.05) in Studies I and II, respectively. The corresponding peak times were 4.68±2.04 h and 1.46±0.17 h (N.S.). The lag time averaged 0.48±0.08 h in Study I and 0.39±0.05 h in Study II (N.S.). The area under the plasma concentration-time curve remained unchanged. The elimination half-life was 15.03±0.61 h and 11.75±0.80 h (p〈0.01) in Studies I and II, respectively. The recovery of unchanged mexiletine in urine and its renal clearance was also the same in both studies. The plasma protein binding of mexiletine was similar in Studies I and II (61±2% and 63±3%; N.S.). Thus, the rate of gastrointestinal absorption of mexiletine was definitely slowed in the acute phase of myocardial infarction, whereas the extent of absorption was not altered. The prolongation of the elimination half-life of mexiletine in the acute phase of myocardial infarction is probably related to an increase in its volume of distribution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00542518
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Disopyramide pharmacokinetics in patients with acute myocardial infarction (1985)
    Springer
    European journal of clinical pharmacology 28 (1985), S. 45-51 
    Details
    ISSN: 1432-1041
    Keywords: disopyramide ; myocardial infarction ; antiarrhythmic agent ; pharmacokinetics ; protein binding ; intravenous administration ; oral administration ; gastro-intestinal absorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary To study the effects of acute myocardial infarction on the pharmacokinetics of disopyramide a single oral dose of disopyramide base (200 mg) was administered to 6 patients with myocardial infarction both in the acute (Study I) and recovery (Study II) phases. An intravenous tracer dose of14C-disopyramide (2.5 µg/0.3 mg) was given simultaneously with the oral dose. On the basis of the intravenous tracer data, the volume of distribution, binding to plasma proteins, total plasma clearance, renal clearance and elimination half-life of disopyramide and mono-N-dealkyl disopyramide were the same in Studies I and II. The peak serum concentrations of disopyramide after oral dosing in Studies I and II were 2.6±1.2 (SEM) and 6.4±1.9 µg/ml, respectively (p〈0.05), the peak times 3.29±1.22 and 1.21±0.39 h (N.S.) and the AUCINF 38.0±7.7 and 60.7±9.9 µg·h·ml−1 (p〈0.05). The recovery of disopyramide in urine over 3 days averaged 46% and 47% of dose, and that of mono-N-dealkyl disopyramide 22% and 16% of the dose, respectively. Thus, the gastrointestinal absorption of disopyramide was disturbed, resulting in low plasma concentrations after oral dosing, whereas the elimination of disopyramide was unaltered in the acute phase of myocardial infarction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00635707
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Cirrhosis of the liver markedly impairs the elimination of mexiletine (1986)
    Springer
    European journal of clinical pharmacology 30 (1986), S. 83-88 
    Details
    ISSN: 1432-1041
    Keywords: mexiletine ; cirrhosis of the liver ; antiarrhythmic agents ; pharmacokinetics ; intravenous administration ; protein binding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary To study the effects of cirrhosis of the liver on the pharmacokinetics of mexiletine a single i.v. dose of 200 mg was administered to six cirrhotic patients and to six healthy controls. The distribution of mexiletine in both study groups was similar, as indicated by similar values of V1 and Vss, but it tended to occur more slowly in the cirrhotics. The plasma protein binding of mexiletine was unchanged in the patients with cirrhosis. The elimination of mexiletine was markedly retarded in the cirrhotics, as indicated by its lower total clearance (2.31 vs. 8.27 ml/kg/h,) lower total elimination rate constant (0.059 vs 0.353 h−1), and longer elimination half-life (28.7 vs 9.9 h). The antipyrine half-life was 38.3 h in the patients and 14.7 h in the controls. One healthy volunteer had a Morgagni-Stokes-Adams type of syncopal attack 5 min after administration of mexiletine due to disturbance of AV conduction induced by the drug. Thus, on a pharmacokinetic basis the loading dose of mexiletine need not be modified in cirrhotic patients, whereas the maintenance dosage should be reduced to one fourth — one third of the usual dose.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00614201
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...