BACTRIM (Antibiotique) : fiche médicament du Vidal de la famille précisant la composition, la posologie, les interactions possibles, les effets indésirables éventuels. taking bactrim when having long qt lovemuffin806 My cardiologist told me I have long qt syndrome not the congential kind and my family doctor prescribed the generic form of bactrim for my sinus and ear infection. This report describes a patient who presented on 2 occasions with QT-interval prolongation and torsades de pointes after oral administration of trimethoprim-sulfamethoxazole. Previous article in issue Ventricular repolarization disturbances. The QT interval, which is the traditional measurement for assessing the duration of ventricular de- and repolarization, is measured in milliseconds (ms) on the body surface electrocardiogram (ECG) from the Q-top, the beginning of the QRS complex, until the end of the T wave. Question. I have heard that trimethoprim / sulfamethoxazole (Septra, Bactrim) causes QT prolongation so is not a good alternative to fluoroquinolones in at-risk patients. The QT interval is dynamic, with a large variability that exists from beat-to-beat, diurnally, and from day-to-day. Other factors that influence the width of the QT interval include concomitant interacting drugs, electrolyte concentrations, and myocardial ischemia [ 10 , 11 ]. The prolonged QT interval is both widely seen and associated with the potentially deadly rhythm, Torsades de Pointes (TdP). While it can occur spontaneously in the congenital form, there is a wide array of drugs that have been implicated in the prolongation of the QT interval. Summary. Electrocardiogram qt corrected interval prolonged is found among people who take Bactrim, especially for people who are female, 40-49 old also take medication Propulsid, and have High blood pressure. For people with LQTS there are specific medications that can have a serious effect by further prolonging the QT interval. We give a list of these medicines below. This list includes drugs that can stimulate and irritate the heart by causing adrenaline-like effects. You must always check with your GP or cardiologist before taking any new medication, as this list will change with time. QT. TdP = United States Food and Drug Administration = intravenous = package insert = QT interval prolongation = torsades de pointes. ECG VF. TCA.