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Pharmacotherapy. 1984 Jul-Aug;4(4):205-10.
Selectivity of bevantolol hydrochloride, a beta 1-adrenoceptor antagonist, in asthmatic patients.

Lofdahl CG, Svedmyr K, Svedmyr N.

Bevantolol hydrochloride, a new beta-adrenoceptor antagonist, has been shown to be cardioselective in animals. To evaluate its selectivity in humans, a double-blind, crossover study was conducted in 8 asthmatics. Following a single oral dose of placebo, bevantolol 75 or 150 mg or propranolol hydrochloride 40 mg, forced expiratory volume in 1 second (FEV1), heart rate, blood pressure and skeletal muscle tremor were measured before and after 4 increasing intravenous doses of terbutaline sulfate to establish terbutaline dose-response curves. The FEV1 decreased after all active treatments. During terbutaline infusions there was an increase in FEV1 after both bevantolol doses and placebo. The terbutaline dose-response curve after bevantolol shifted to the right, however. After propranolol, there was no increase in FEV1 during terbutaline stimulation. Heart rate and skeletal muscle tremor showed a similar pattern during the experiment. In dosages that have previously been shown to produce at least the same degree of blockade of exercise-induced tachycardia, bevantolol has less influence on terbutaline-induced bronchodilation, heart rate increase and skeletal muscle tremor than did propranolol. Thus bevantolol has relative beta 1-adrenoceptor antagonist selectivity. Drawing upon the results of a previous study in the same patients, we believe bevantolol, atenolol and metoprolol have similar beta 1-selectivity.

online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6148733&dopt=Abstract

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The stability of drugs commonly prescribed for use in oral liquid dosage forms but not commercially available as such was studied. Labetalol hydrochloride 40 mg/mL, metoprolol tartrate 10 mg/mL, verapamil hydrochloride 50 mg/mL, and spironolactone 5 mg/mL plus hydrochlorothiazide 5 mg/ mL were prepared in a 1:1 mixture of Ora-Sweet and Ora-Plus (Paddock Laboratories), a 1:1 mixture of Ora-Sweet SF and Ora-Plus (Paddock Laboratories), and cherry syrup and placed in polyethylene terephthalate bottles. The sources of the drugs were tablets. Six bottles were prepared per liquid; three were stored at 5 degrees C and three at 25 degrees C, all in the dark. A sample was removed from each bottle initially and at intervals up to 60 days and analyzed for drug concentration by stability-indicating high-performance liquid chromatography. At least 91% of the initial drug concentration was retained in all the oral liquids for up to 60 days. There were no substantial changes in the appearance or odor of the liquids, or in the pH. Labetalol hydrochloride 40 mg/mL, metoprolol tartrate 10 mg/mL, verapamil hydrochloride 50 mg/mL, plus hydrochlorothiazide 5 mg/ mL in three oral liquids compounded extemporaneously from sweetened vehicles and tablets were stable for up to 60 days when stored without light at 5 and 25 degrees C.

online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8893069&dopt=Abstract




J Chromatogr A. 2001 Jan 5;905(1-2):3-17.
Influence of the solute hydrophobicity on the enantioselective adsorption of beta-blockers on a cellulase protein used as the chiral selector.

Gotmar G, Fornstedt T, Andersson M, Guiochon G.

Department of Pharmacy, BMC, Uppsala, Sweden.

Adsorption isotherm data were acquired at different eluent pH values for the enantiomers of several beta-blockers on cellobiohydrolase I on silica gel. They fit well to the biLangmuir model, allowing the determination of the equilibrium constants and the monolayer capacities for chiral and nonselective adsorption. The adsorption of the S-enantiomers (eluted second) is exothermic at low pH, endothermic at high pH, and athermal in a narrow pH range depending on the beta-blocker. This transition pH range is lower for S-alprenolol than for the more hydrophobic S-propranolol, although their endothermic adsorption originates from hydrophobic interactions. This surprising observation is explained by the relative values of the isotherm coefficients. S-Alprenolol seems to have a more pronounced endothermic behavior than S-propranolol because the nonselective interactions of both compounds with the stationary phase are exothermic but their contribution to retention, relative to that of the endothermic chiral interactions, is less important for alprenolol. The order of increasing energy of the chiral interactions is the same as that of hydrophobicity, propranolol>alprenolol>metoprolol.

online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11206798&dopt=Abstract













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