Do not take Cardoreg 4 mg prolonged release tablets and associated names • if you are allergic to doxazosin or to any of the ingredients listed above • if you know that you are sensitive to quinazolines (e. g. prazosin, terazosin) which is the chemical family of medicines to which doxazosin belongs • if you suffer or have suffered from any form of obstruction of the digestive tract • if you have an infection or an obstruction of the urinary tract or bladder stones • if you suffer from kidney problems, overflow incontinence (you do not feel the urge to urinate) or anuria (your body is not producing any urine) • if you are breast-feeding