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Relationships among timolol doses, plasma concentrations and beta-adrenoceptor blocking activity.

R K Ferguson·P H Vlasses·J R Koplin·G I Holmes·P Huber·J Demetriades·W B Abrams
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Abstract

1 We investigated the relationships among dose, plasma concentration and beta-adrenoceptor blockade after single and repeated doses (0.5-20 mg) of timolol and placebo in six normal men. 2 Maximal suppression of exercise-induced tachycardia (bicycle ergometry) was dose-dependent and greater at 2 than at 6 h after dosing; activity up to 12 h was evident on the last dosing day. 3 Attenuation of exercise-induced tachycardia was strongly correlated with the timolol dosage over the 0.5 to 5-10 mg range. 4 A plasma timolol concentration of 27 ng/ml was associated with maximal suppression of exercise-induced tachycardia. 5 Suppression of exercise-induced tachycardia and areas under the plasma concentration-time curves did not differ significantly on the first and last dosing days.

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Adrenergic beta-AntagonistsAdultDose-Response Relationship, DrugHeart RateHumansMalePhysical ExertionPropanolaminesReninTimololClinical TrialControlled Clinical TrialJournal Article

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R K Ferguson, P H Vlasses, J R Koplin, G I Holmes, P Huber, J Demetriades, W B Abrams. 1982. Relationships among timolol doses, plasma concentrations and beta-adrenoceptor blocking activity.. https://doi.org/10.1111/j.1365-2125.1982.tb04963.x

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