-
Views
-
Cite
Cite
Peter A. Meredith, Andrew Koren, P-172: A placebo-controlled comparison of the effects of doxazosin GITS 4mg and doxazosin standard 1mg on blood pressure and heart rate, American Journal of Hypertension, Volume 18, Issue S4, May 2005, Page 69A, https://doi.org/10.1016/j.amjhyper.2005.03.190
Close - Share Icon Share
Abstract
One of the primary aims of the development of the doxazosin GITS was to allow the initiation of therapy at a higher dose than with the conventional formulation of doxazosin and thereby to reduce the need for dose titration. This characteristic has potential importance for initiating therapy in hypertension and benign prostatic hyperplasia.
This study investigated the hemodynamic responses to single doses of doxazosin GITS 4 mg, doxazosin standard 1 mg, and placebo administered at one week intervals in a double blind, placebo controlled, randomized, 3-way crossover study in 24 normotensives aged 40–70 years (mean 52.6±8.2).
The blood pressure and heart rate responses to doxazosin (standard and GITS) were analysed following individual placebo correction of each data point. The orthostatic changes over the 24-hour period, were calculated from standing BP or heart rate minus supine BP or heart rate. maximum orthostatic change in blood pressure and pulse rate. There were no statistically significant differences between the two doxazosin formulations for supine and erect BP and hear rate. The mean maximum falls in supine BP were −6.4/−2.6mmHg (systolic/diastolic) for doxazosin GITS (8–11 hours post dose) and −7.6/−4.1mmHg for doxazosin standard (6–9 hours post dose). The values for standing BP were −7.9/−5.6mmHg and −7.9/−5.8mmHg for doxazosin GITS and standard, respectively. No statistically significant differences between the two formulations were observed in the maximum orthostatic changes in systolic and diastolic BP over the 24-hour period. Orthostatic heart rate was increased by both treatments to a similar extent with maximum increases that did not exceed 10 beats per minute.
The study demonstrated that single doses of doxazosin GITS 4 mg were as safe and as well tolerated as single doses of doxazosin standard 1 mg and placebo based on orthostatic responses and reported adverse events. This provides reassurance treatment may be initiated at a higher dose using the GITS formulation even in patients with normotensive BP levels.
