In some cases, this is due to over-correction with Bazett's formula.

For some drugs, such as sotalol, amisulpride and citalopram or escitalopram, there is a lot of information on the risk of QT prolongation and torsades de pointes (QT prolongation may be due to multiple factors or more than one drug. Haverkamp W, Eckardt L, Monnig G, et al. Standard ECG machines can be unreliable and taking the automated reading from the ECG machine in clinical practice may be inaccurate, particularly in patients with a long QT. The following drugs have beeen added to the Possible Risk of TdP list because we have found evidence of QT prolongation with their use but, at this time, we have not found convincing evidence of torsades de pointes (TdP). Additionally, some of these medications are more likely to cause QT prolongation than others. In order for us to create your customized HealthSavvy programs, we need a little more information about the health topic(s) that you are interested in.

Also, QT-prolonging medications should generally not be used in combination, as this increases the risk of problems.

Philadelphia (PA); 2000.

Fluothane (halothane) package insert.
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