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Journal of Clinical Pharmacology Mar 1995The negative inotropic and chronotropic effects of beta-blocker therapy have been reported to reduce morbidity and mortality in patients with Marfan syndrome; however,... (Comparative Study)
Comparative Study
The negative inotropic and chronotropic effects of beta-blocker therapy have been reported to reduce morbidity and mortality in patients with Marfan syndrome; however, little is known about the pharmacokinetics of atenolol after oral administration of multiple doses to patients with the Marfan syndrome. We studied the pharmacokinetics of atenolol in 13 such patients aged 18.7 +/- 2.9 years who were receiving 1.78 +/- 0.58 mg/kg/day (70.1 +/- 20.3 mg/m2/day) of atenolol for 6 weeks or longer. Mean +/- SD percentage change in baseline heart rate after the administration of atenolol was -18.03 +/- 16.59% and mean +/- SD percentage change in exercise heart rate after atenolol was -33.22 +/- 14.75% (P < .01). Six to 8 atenolol serum concentrations were collected in each patient during a 12-hour dosing interval and were determined by high-performance liquid chromatography with ultraviolet detection. Serum atenolol concentrations at 0 (123 +/- 70 micrograms/L) and 12 (116 +/- 66 micrograms/L) hours were within 20% of each other and were thus assumed to be at steady-state. A one-compartment, steady-state pharmacokinetic model with first-order absorption and elimination was fitted to the concentration-time data for each patient using nonlinear regression. Maximal concentration was 343 +/- 120 micrograms/L, and the mean half-life was 4.72 hours.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Absorption; Administration, Oral; Adolescent; Adult; Atenolol; Drug Administration Schedule; Exercise Test; Half-Life; Heart Rate; Humans; Marfan Syndrome; Metabolic Clearance Rate
PubMed: 7608315
DOI: 10.1002/j.1552-4604.1995.tb04057.x -
Chemosphere Nov 2013Photoactivation of peroxymonosulfate (PMS) with UV (254nm) irradiation was used to generate the SO4(-)-based advanced oxidation process, which was adopted to degrade...
Photoactivation of peroxymonosulfate (PMS) with UV (254nm) irradiation was used to generate the SO4(-)-based advanced oxidation process, which was adopted to degrade atenolol (ATL) in water. The second-order reaction rate constants of ATL with HO and SO4(-) were determined, and the effects of operational parameters (dose of PMS, solution pH, HCO3(-), humic acids (HA), and N2 bubbling) were evaluated as well. Finally the main transformation intermediates were identified and possible degradation pathways were proposed. The results showed that there was a linear positive correlation between the degradation rate of ATL and specific dose of PMS (1-16M PMS/M ATL). Increasing solution pH from 3 to 9 promoted elimination of ATL due to the pH-dependent effect of PMS photodecomposition, while further pH increase from 9 to 11 caused slowing down of degradation because of apparent conversion of HO to SO4(-). 1-8mM HCO3(-) exerted no more than 5.3% inhibition effect on ATL destruction, suggesting HCO3(-) was a weak inhibitor. Absorption (or complexation) and photosensitized oxidation induced by HA improved ATL degradation during the first minute of degradation process, whereas photon competition and radical scavenging effects became the leading role afterward. Bubbling with nitrogen enhanced the degradation rate due to the stripping of dissolved oxygen. Hydroxylation of aromatic ring, cleavage of ether bond, oxidation of primary and secondary amine moieties, and dimerization were involved in the degradation mechanism of ATL by UV/PMS.
Topics: Atenolol; Kinetics; Peroxides; Photolysis; Ultraviolet Rays; Water Pollutants, Chemical; Water Purification
PubMed: 24083900
DOI: 10.1016/j.chemosphere.2013.08.090 -
Journal of Chromatographic Science 2012This paper describes a high-performance liquid chromatography method for the determination of atenolol in human plasma. Atenolol and the internal standard, metoprolol,...
This paper describes a high-performance liquid chromatography method for the determination of atenolol in human plasma. Atenolol and the internal standard, metoprolol, were extracted from plasma by using a liquid-liquid extraction method. The method was developed on an Ace C18 reverse-phase column using a mobile phase of methanol-water (50:50, v/v) containing 0.1% trifluoroacetic acid. The calibration curve was linear within the concentration range of 5-150 ng/mL. Intra-day and inter-day precision values for atenolol in plasma were less than 6.1, and accuracy (relative error) was better than 5.5%. The mean recovery of atenolol was 98.4% for plasma. The limits of detection and quantification of atenolol were 1.5 and 5 ng/mL, respectively. Also, this assay was successfully applied to six patients with hypertension who had been given an oral tablet of 50 mg atenolol.
Topics: Administration, Oral; Antihypertensive Agents; Atenolol; Chromatography, High Pressure Liquid; Drug Stability; Humans; Hypertension; Least-Squares Analysis; Limit of Detection; Male; Metoprolol; Reproducibility of Results; Turkey
PubMed: 22718748
DOI: 10.1093/chromsci/bms090 -
Biopharmaceutics & Drug Disposition 1991This double-blind randomized, crossover study was undertaken to determine the pharmacokinetic properties of nifedipine retard and atenolol when given separately, as a... (Clinical Trial)
Clinical Trial Comparative Study Randomized Controlled Trial
This double-blind randomized, crossover study was undertaken to determine the pharmacokinetic properties of nifedipine retard and atenolol when given separately, as a free or a fixed combination, compared with placebo in 15 healthy male volunteers. There was no difference between the three atenolol formulations in time to maximum blood concentration or elimination half-life. The fixed combination showed significant differences in both maximum observed blood concentrations (+16 per cent) and total area under the curve (+16 per cent) compared to atenolol alone. Urinary recovery of unchanged drug from the fixed combination was also slightly increased but the difference was not statistically significant. Furthermore, statistical evaluation of the plasma pharmacokinetics of nifedipine retard and urinary recovery of nifedipine metabolite showed that all three formulations were indistinguishable. Thus, it is concluded that the fixed combination of nifedipine and atenolol is bioequivalent to the free combination and that the bioavailability of both drugs in the fixed combination is equivalent to that of the single entities.
Topics: Adult; Atenolol; Biological Availability; Blood Pressure; Double-Blind Method; Drug Combinations; Drug Therapy, Combination; Heart Rate; Humans; Male; Nifedipine
PubMed: 2039814
DOI: 10.1002/bdd.2510120109 -
Clinical Pharmacy 1983The efficacy and safety of atenolol was evaluated in 16 patients with exertional angina pectoris in a single-blind, once daily, increasing dose study. All patients had... (Clinical Trial)
Clinical Trial
The efficacy and safety of atenolol was evaluated in 16 patients with exertional angina pectoris in a single-blind, once daily, increasing dose study. All patients had coronary artery disease documented by previous myocardial infarction, coronary angiography, or an abnormal exercise ECG. After a four-week placebo period, patients received 25, 50, and 100 mg of atenolol once daily during three two-week periods. This was followed by a three-week treatment period with 200 mg of atenolol once daily. The study was concluded with a two to four week posttreatment period. Antianginal efficacy was assessed by monitoring changes in treadmill exercise performance in each patient 3 and 24 hours after the administration of atenolol. The endpoint of the treadmill exercise was mild but definite chest pain. At 3 and 24 hours after all dosages, atenolol significantly prolonged the duration of exercise and increased the work performed. The pulse rate and double product at the endpoint of exercise were lower with all atenolol doses. Overall, at 24 hours after the administration of atenolol, exercise tolerance was progressively increased as the dose increased. The mean duration of exercise and work performed increased 28.5 and 35.4%, respectively, on the 25-mg dose; 36.9 and 45.5%, respectively, on the 50-mg dose; 45.1 and 59.5%, respectively, on the 100-mg dose; and 65.4 and 84.8%, respectively, on the 200-mg dose. Patient acceptance and compliance were good. Single daily doses of atenolol constitute effective therapy for exercise-induced angina.
Topics: Aged; Angina Pectoris; Atenolol; Clinical Trials as Topic; Dose-Response Relationship, Drug; Exercise Test; Humans; Male; Middle Aged; Physical Exertion; Propanolamines; Time Factors
PubMed: 6349909
DOI: No ID Found -
The New Zealand Medical Journal Nov 1980Thirty hypertensive patients treated with a drug regimen which contained a beta-receptor antagonist (either propranolol, pindolol or metoprolol) exhibited an improvement...
Thirty hypertensive patients treated with a drug regimen which contained a beta-receptor antagonist (either propranolol, pindolol or metoprolol) exhibited an improvement in blood pressure control when atenolol was substituted for the corresponding beta-blocker in the drug regimen. Additional benefits noted were a reduction in concomitant drug therapy and an improvement in reported side effects. Atenolol caused a significant decrease in heart rate in the group for which the mean follow-up period was 23.6 months.
Topics: Adult; Aged; Atenolol; Drug Evaluation; Drug Therapy, Combination; Female; Follow-Up Studies; Humans; Hypertension; Male; Metoprolol; Middle Aged; Pindolol; Propanolamines; Propranolol
PubMed: 6937768
DOI: No ID Found -
The British Journal of Ophthalmology May 1978Topical atenolol (a beta1-adrenoceptive antagonist), pilocarpine, and placebo were tested in a randomised double-blind crossover trial of 8 patients with ocular... (Clinical Trial)
Clinical Trial Comparative Study Randomized Controlled Trial
Topical atenolol (a beta1-adrenoceptive antagonist), pilocarpine, and placebo were tested in a randomised double-blind crossover trial of 8 patients with ocular hypertenion. Atenolol (2% 3 times a day) caused a fall in intraocular pressure (IOP) comparable to that achieved by topical application of pilocarpine (2% 3 times a day). The decrease in IOP by each compound was demonstrable on the second day of application and was significantly (P is less than 0.05) reduced on the seventh and 14th days of treatment. The combination of 2% pilocarpine and 2% atenolol administered 15 minutes apart (3 times a day) lowered the IOP significantly from the second day of treatment, and this reduction persisted throughout the trial period of 14 days. This combined of treatment, treatment lowered the IOP more than either substance alone. However, this further decrease was statistically significant only on the 14th day of treatment (atenolol versus atenolol + pilocarpine, P is less than 0.05). No change of the episcleral venous pressure was observed after 14 days' treatment with either atenolol or pilocarpine alone, or combined.
Topics: Adult; Aged; Atenolol; Clinical Trials as Topic; Double-Blind Method; Drug Therapy, Combination; Female; Humans; Intraocular Pressure; Male; Middle Aged; Ophthalmic Solutions; Pilocarpine; Propanolamines
PubMed: 350263
DOI: 10.1136/bjo.62.5.292 -
Headache Jul 1987
Clinical Trial
Topics: Adult; Atenolol; Clinical Trials as Topic; Double-Blind Method; Female; Humans; Male; Middle Aged; Migraine Disorders
PubMed: 3308768
DOI: 10.1111/j.1526-4610.1987.hed2707372.x -
International Journal of Pharmaceutical... 2012The purpose of this study was to formulate a 25-mg atenolol capsule starting from a commercial 100-mg atenolol tablet, given the fact that this strength is not available...
The purpose of this study was to formulate a 25-mg atenolol capsule starting from a commercial 100-mg atenolol tablet, given the fact that this strength is not available in Palestine and also because 50-mg atenolol tablets failed the splitting uniformity test of the European Pharmacopoeia, and to evaluate the chemical stability and dissolution behavior of the obtained capsules so as to ensure a high-quality product. A high-performance liquid chromatographic system was used for the analysis and quantification of atenolol in the samples studied. Samples of atenoIol for analysis were prepared as reported by the United States Pharmacopeia monograph. Disintegration and dissolution tests were performed according to the United States Pharmacopeia. The high-performance liquid chromatography assay indicated that the 25-mg atenolol capsules were stable for four months when stored at ambient temperature conditions. The disintegration time for all atenolol capsules was within the United States Pharmacopeia limits of 15 minutes. Atenolol release profile showed that approximately 90% of atenolol dissolved after 10 minutes. This study is important for patients who need to take one half of a 50-mg tablet, but for whom the splitting process doesn't give equal halves, and also for modifying the dose for patients with renal or hepatic problems. Therefore, it is possible for the community pharmacist to crush atenolol 100-mg tablets and refill them in new capsules with each containing a precise amount of atenolol, calculated according to body surface area and kidney and liver functions without affecting the chemical stability of the active ingredient nor its dissolution profile and also have a cost effective dosage form.
Topics: Adrenergic beta-Antagonists; Atenolol; Capsules; Chemistry, Pharmaceutical; Drug Stability; Quality Control; Solubility; Tablets
PubMed: 23050394
DOI: No ID Found -
European Journal of Clinical... Nov 1978Maternal and umbilical serum concentrations of atenolol, a hydrophilic, cardioselective beta-adrenoceptor antagonist, were studied at delivery in seven cases of...
Maternal and umbilical serum concentrations of atenolol, a hydrophilic, cardioselective beta-adrenoceptor antagonist, were studied at delivery in seven cases of pregnancy hypertension. The drug had been administered to each patient for at least one week. Atenolol was detected in both maternal and umbilical serum in six cases, showing that there is transplacental passage of the drug. In the seventh case, who had stopped taking atenolol more than one day before delivery, neither maternal nor umbilical serum contained a measurable quantity of the drug. Atenolol concentration varied 3- to 6-fold between individuals, but there was no systematic difference between maternal and umbilical levels. It seems reasonable to assume that during steady state conditions the blood level of atenolol in mother and fetus is approximately equal, and that fetal accumulation of the drug does not occur.
Topics: Adult; Atenolol; Female; Half-Life; Humans; Infant, Newborn; Maternal-Fetal Exchange; Placenta; Pregnancy; Propanolamines; Time Factors
PubMed: 720380
DOI: 10.1007/BF00607437