The doxazosin gastrointestinal therapeutic system (GITS) tablet (Cardura
XL) has a half-life of 16-30 hours and is designed to provide a controlled rate of delivery into the GI lumen, independent of pH or GI motility.
You may recall that several years ago there was a trial that showed that one prescription medication, doxazosin (Cardura
), was as good as other anti-hypertensive drugs at lowering blood pressure; but unlike those drugs, doxazosin did not decrease heart attacks and strokes.
Briefly, 33,000 patients were randomly studied using chlorthalidone, a thiazide diuretic available generically; amlodipine (Norvasc); lisinopril (Prinivil); and doxazosine (Cardura
This is another instance in a long line of postmarketing disasters including Rezulin, Cardura
, and Posicor.
(Commonly used alpha blockers include Minipress, Hytrin, Cardura
Reserve the far costlier alternatives, doxazosin (Cardura
) and tamsulosin (Flomax), for men who experience unacceptable side effects on terazosin.
doxazosin mesylate (Cardura
) guanfacine HCI (Tenex) hydralazine HCI (Apresoline) labetalol HCI (Normodyne, Trandate) metoprolol tartrate (Lopressor, Toprol XL) nadolol (Corgard) prazosin HCI (Minipress) terazosin HCI (Hytrin) valsartan (Diovan) Psychotherapeutic medications amitriptyline HCI (Elavil) Treats depression.
The NIH is recruiting men for a five-year trial set to begin in 1995 that will study the effects of Proscar and the drug doxazosin (Cardura
) on BPH.
The plant, which will produce Cardura
monomer, a Versatic acid derivative, will be constructed within an existing manufacturing complex of the company in Onsan.
The results from the terazosin (Hytrin) and doxazosin (Cardura
) studies were included with the tamsulosin studies.
The company has also announced that it is terminating a supply and distribution agreement for Cardura
XL (Pfizer Inc.), since the Food and Drug Administration had failed to approve the medication by the end of last year.
The FDA's Cardiovascular and Renal Durgs Advisory Committee addressed the issue in response to a citizen's petition filed on behalf of men on doxazosin, The drug is marketed as Cardura
by Pfizer Inc.
The list--a veritable pharmaceutical hit-parade--includes loratadine (Claritin), astemizole (Hismanal), cetirizine (Zyrtec), fluoxetine (Prozac), doxazosin (Cardura
), itraconazole (Sporanox), bupropion (Zyban), amlodipine (Norvasc), and formoterol (Foradil).
Use PDE-5s with caution if you already take drugs known as alpha-blockers--doxazosin (Cardura
) and terazosin (Hytrin) are examples--or other blood pressure-lowering medications.
ALLHAT, the largest hypertensive trial ever conducted, randomized 15,255 patients to chlorthalidone, 9061 to doxazosin (Cardura
), 9048 to amlodipine, and 9054 to lisinopril (Prinivil/Zestril).