The injectable form of dolasetron mesylate (Anzemet) should not be used to prevent nausea or vomiting related to chemotherapy because the drug increases the risk for torsade de pointes, the FDA announced on Friday.

The FDA recommends against using Anzemet injections in patients with congenital long-QT syndrome.

The warning does not apply to Anzemet tablets because the risks for developing an abnormal heart rhythm are not as high as with the injections