The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
P J Neuvonen - One of the best experts on this subject based on the ideXlab platform.
-
Effects of orange juice on the pharmacokinetics of Atenolol
European Journal of Clinical Pharmacology, 2005Co-Authors: Jari J. Lilja, K Raaska, P J NeuvonenAbstract:Objective Fruit juices can significantly change the pharmacokinetics of several drugs. Our objective was to investigate the effect of orange juice on the pharmacokinetics of the beta-blocking agent Atenolol. Methods In a randomized cross-over study with two phases and a washout of 2 weeks, ten healthy volunteers took either 200 ml orange juice or water thrice daily for 3 days and twice on the fourth day. On the morning of day 3, each subject ingested 50 mg Atenolol with an additional amount of either 200 ml orange juice or water. The plasma concentrations of Atenolol and the cumulative excretion of Atenolol into urine were measured up to 33 h after its dosing. Systolic and diastolic blood pressures and heart rate were recorded in a sitting position before the intake of Atenolol and 2, 4, 6, and 10 h after. Results Orange juice decreased the mean peak plasma concentration ( C _max) of Atenolol by 49% (range 16–59%, P
-
Effects of orange juice on the pharmacokinetics of Atenolol.
European journal of clinical pharmacology, 2005Co-Authors: Jari J. Lilja, K Raaska, P J NeuvonenAbstract:Fruit juices can significantly change the pharmacokinetics of several drugs. Our objective was to investigate the effect of orange juice on the pharmacokinetics of the beta-blocking agent Atenolol. In a randomized cross-over study with two phases and a washout of 2 weeks, ten healthy volunteers took either 200 ml orange juice or water thrice daily for 3 days and twice on the fourth day. On the morning of day 3, each subject ingested 50 mg Atenolol with an additional amount of either 200 ml orange juice or water. The plasma concentrations of Atenolol and the cumulative excretion of Atenolol into urine were measured up to 33 h after its dosing. Systolic and diastolic blood pressures and heart rate were recorded in a sitting position before the intake of Atenolol and 2, 4, 6, and 10 h after. Orange juice decreased the mean peak plasma concentration (C(max)) of Atenolol by 49% (range 16-59%, P<0.01), and the mean area under the plasma Atenolol concentration-time curve (AUC(0-33 h)) by 40% (range 25-55%, P<0.01). The time of the peak concentration (t(max)) and the elimination half-life (t(1/2)) of Atenolol remained unchanged by orange juice. The amount of Atenolol excreted into urine was decreased by 38% (range 17-60%, P<0.01), but the renal clearance remained unaltered. The average heart rate was slightly higher during the orange juice+Atenolol phase than during the water+Atenolol phase. Orange juice moderately interferes with the gastrointestinal absorption of Atenolol. This food-drug interaction can be of clinical significance.
Jari J. Lilja - One of the best experts on this subject based on the ideXlab platform.
-
Effect of Itraconazole on the Pharmacokinetics of Atenolol
Basic & Clinical Pharmacology & Toxicology, 2005Co-Authors: Jari J. Lilja, Janne T. BackmanAbstract:Abstract: Our objective was to evaluate the effect of itraconazole on the pharmacokinetics of Atenolol in healthy volunteers. In a randomized cross-over study with two phases, 10 healthy volunteers had 200 mg itraconazole orally or placebo for 2 days b.i.d., and in the morning of day 3, one hour after the last ingestion of itraconazole or placebo, each subject received 50 mg Atenolol. The plasma concentrations of Atenolol and its excretion into urine were measured up to 33 hr. Blood pressures and heart rate were recorded up to 10 hr. Itraconazole had no statistically significant effect on any of the pharmacokinetic or pharmacodynamic variables of Atenolol. If anything, itraconazole increased the area under the plasma concentration-time curve (+12%; P=0.159), peak plasma concentration (+19%; P=0.165), and amount of Atenolol excreted into urine (+13%; P=0.166) suggesting a slight increase of Atenolol bioavailability. It can be concluded that itraconazole does not have a clinically relevant effect on the pharmacokinetics of Atenolol.
-
Effects of orange juice on the pharmacokinetics of Atenolol
European Journal of Clinical Pharmacology, 2005Co-Authors: Jari J. Lilja, K Raaska, P J NeuvonenAbstract:Objective Fruit juices can significantly change the pharmacokinetics of several drugs. Our objective was to investigate the effect of orange juice on the pharmacokinetics of the beta-blocking agent Atenolol. Methods In a randomized cross-over study with two phases and a washout of 2 weeks, ten healthy volunteers took either 200 ml orange juice or water thrice daily for 3 days and twice on the fourth day. On the morning of day 3, each subject ingested 50 mg Atenolol with an additional amount of either 200 ml orange juice or water. The plasma concentrations of Atenolol and the cumulative excretion of Atenolol into urine were measured up to 33 h after its dosing. Systolic and diastolic blood pressures and heart rate were recorded in a sitting position before the intake of Atenolol and 2, 4, 6, and 10 h after. Results Orange juice decreased the mean peak plasma concentration ( C _max) of Atenolol by 49% (range 16–59%, P
-
Effects of orange juice on the pharmacokinetics of Atenolol.
European journal of clinical pharmacology, 2005Co-Authors: Jari J. Lilja, K Raaska, P J NeuvonenAbstract:Fruit juices can significantly change the pharmacokinetics of several drugs. Our objective was to investigate the effect of orange juice on the pharmacokinetics of the beta-blocking agent Atenolol. In a randomized cross-over study with two phases and a washout of 2 weeks, ten healthy volunteers took either 200 ml orange juice or water thrice daily for 3 days and twice on the fourth day. On the morning of day 3, each subject ingested 50 mg Atenolol with an additional amount of either 200 ml orange juice or water. The plasma concentrations of Atenolol and the cumulative excretion of Atenolol into urine were measured up to 33 h after its dosing. Systolic and diastolic blood pressures and heart rate were recorded in a sitting position before the intake of Atenolol and 2, 4, 6, and 10 h after. Orange juice decreased the mean peak plasma concentration (C(max)) of Atenolol by 49% (range 16-59%, P<0.01), and the mean area under the plasma Atenolol concentration-time curve (AUC(0-33 h)) by 40% (range 25-55%, P<0.01). The time of the peak concentration (t(max)) and the elimination half-life (t(1/2)) of Atenolol remained unchanged by orange juice. The amount of Atenolol excreted into urine was decreased by 38% (range 17-60%, P<0.01), but the renal clearance remained unaltered. The average heart rate was slightly higher during the orange juice+Atenolol phase than during the water+Atenolol phase. Orange juice moderately interferes with the gastrointestinal absorption of Atenolol. This food-drug interaction can be of clinical significance.
Xiaomei Chen - One of the best experts on this subject based on the ideXlab platform.
-
revisiting Atenolol as a low passive permeability marker
Fluids and Barriers of the CNS, 2017Co-Authors: Xiaomei Chen, Tim Slattengren, Elizabeth C M De Lange, David C Smith, Margareta HammarlundudenaesAbstract:Atenolol, a hydrophilic beta blocker, has been used as a model drug for studying passive permeability of biological membranes such as the blood–brain barrier (BBB) and the intestinal epithelium. However, the extent of S-Atenolol (the active enantiomer) distribution in brain has never been evaluated, at equilibrium, to confirm that no transporters are involved in its transport at the BBB. To assess whether S-Atenolol, in fact, depicts the characteristics of a low passive permeable drug at the BBB, a microdialysis study was performed in rats to monitor the unbound concentrations of S-Atenolol in brain extracellular fluid (ECF) and plasma during and after intravenous infusion. A pharmacokinetic model was developed, based on the microdialysis data, to estimate the permeability clearance of S-Atenolol into and out of brain. In addition, the nonspecific binding of S-Atenolol in brain homogenate was evaluated using equilibrium dialysis. The steady-state ratio of unbound S-Atenolol concentrations in brain ECF to that in plasma (i.e., Kp,uu,brain) was 3.5% ± 0.4%, a value much less than unity. The unbound volume of distribution in brain (Vu, brain) of S-Atenolol was also calculated as 0.69 ± 0.10 mL/g brain, indicating that S-Atenolol is evenly distributed within brain parenchyma. Lastly, equilibrium dialysis showed limited nonspecific binding of S-Atenolol in brain homogenate with an unbound fraction (fu,brain) of 0.88 ± 0.07. It is concluded, based on Kp,uu,brain being much smaller than unity, that S-Atenolol is actively effluxed at the BBB, indicating the need to re-consider S-Atenolol as a model drug for passive permeability studies of BBB transport or intestinal absorption.
K Raaska - One of the best experts on this subject based on the ideXlab platform.
-
Effects of orange juice on the pharmacokinetics of Atenolol
European Journal of Clinical Pharmacology, 2005Co-Authors: Jari J. Lilja, K Raaska, P J NeuvonenAbstract:Objective Fruit juices can significantly change the pharmacokinetics of several drugs. Our objective was to investigate the effect of orange juice on the pharmacokinetics of the beta-blocking agent Atenolol. Methods In a randomized cross-over study with two phases and a washout of 2 weeks, ten healthy volunteers took either 200 ml orange juice or water thrice daily for 3 days and twice on the fourth day. On the morning of day 3, each subject ingested 50 mg Atenolol with an additional amount of either 200 ml orange juice or water. The plasma concentrations of Atenolol and the cumulative excretion of Atenolol into urine were measured up to 33 h after its dosing. Systolic and diastolic blood pressures and heart rate were recorded in a sitting position before the intake of Atenolol and 2, 4, 6, and 10 h after. Results Orange juice decreased the mean peak plasma concentration ( C _max) of Atenolol by 49% (range 16–59%, P
-
Effects of orange juice on the pharmacokinetics of Atenolol.
European journal of clinical pharmacology, 2005Co-Authors: Jari J. Lilja, K Raaska, P J NeuvonenAbstract:Fruit juices can significantly change the pharmacokinetics of several drugs. Our objective was to investigate the effect of orange juice on the pharmacokinetics of the beta-blocking agent Atenolol. In a randomized cross-over study with two phases and a washout of 2 weeks, ten healthy volunteers took either 200 ml orange juice or water thrice daily for 3 days and twice on the fourth day. On the morning of day 3, each subject ingested 50 mg Atenolol with an additional amount of either 200 ml orange juice or water. The plasma concentrations of Atenolol and the cumulative excretion of Atenolol into urine were measured up to 33 h after its dosing. Systolic and diastolic blood pressures and heart rate were recorded in a sitting position before the intake of Atenolol and 2, 4, 6, and 10 h after. Orange juice decreased the mean peak plasma concentration (C(max)) of Atenolol by 49% (range 16-59%, P<0.01), and the mean area under the plasma Atenolol concentration-time curve (AUC(0-33 h)) by 40% (range 25-55%, P<0.01). The time of the peak concentration (t(max)) and the elimination half-life (t(1/2)) of Atenolol remained unchanged by orange juice. The amount of Atenolol excreted into urine was decreased by 38% (range 17-60%, P<0.01), but the renal clearance remained unaltered. The average heart rate was slightly higher during the orange juice+Atenolol phase than during the water+Atenolol phase. Orange juice moderately interferes with the gastrointestinal absorption of Atenolol. This food-drug interaction can be of clinical significance.
Margareta Hammarlundudenaes - One of the best experts on this subject based on the ideXlab platform.
-
revisiting Atenolol as a low passive permeability marker
Fluids and Barriers of the CNS, 2017Co-Authors: Xiaomei Chen, Tim Slattengren, Elizabeth C M De Lange, David C Smith, Margareta HammarlundudenaesAbstract:Atenolol, a hydrophilic beta blocker, has been used as a model drug for studying passive permeability of biological membranes such as the blood–brain barrier (BBB) and the intestinal epithelium. However, the extent of S-Atenolol (the active enantiomer) distribution in brain has never been evaluated, at equilibrium, to confirm that no transporters are involved in its transport at the BBB. To assess whether S-Atenolol, in fact, depicts the characteristics of a low passive permeable drug at the BBB, a microdialysis study was performed in rats to monitor the unbound concentrations of S-Atenolol in brain extracellular fluid (ECF) and plasma during and after intravenous infusion. A pharmacokinetic model was developed, based on the microdialysis data, to estimate the permeability clearance of S-Atenolol into and out of brain. In addition, the nonspecific binding of S-Atenolol in brain homogenate was evaluated using equilibrium dialysis. The steady-state ratio of unbound S-Atenolol concentrations in brain ECF to that in plasma (i.e., Kp,uu,brain) was 3.5% ± 0.4%, a value much less than unity. The unbound volume of distribution in brain (Vu, brain) of S-Atenolol was also calculated as 0.69 ± 0.10 mL/g brain, indicating that S-Atenolol is evenly distributed within brain parenchyma. Lastly, equilibrium dialysis showed limited nonspecific binding of S-Atenolol in brain homogenate with an unbound fraction (fu,brain) of 0.88 ± 0.07. It is concluded, based on Kp,uu,brain being much smaller than unity, that S-Atenolol is actively effluxed at the BBB, indicating the need to re-consider S-Atenolol as a model drug for passive permeability studies of BBB transport or intestinal absorption.