US FDA has put a class of antiemetic drugs, including ondansetron on its
latest quarterly list of products to monitor because of potential
signals of an increased risk for serotonin syndrome.
beta blocker metoprolol succinate also landed on the list because of reports
that suggested therapeutic ineffectiveness.
on the watch list does not mean that the agency has concluded that the drug
poses the health risk reported through FAERS. What it does mean is that the FDA
will investigate whether there is a causal connection.
antiemetics on the watch list belong to a subtype of serotonin blockers that
bind to the 5-HT3 receptor. Serotonin syndrome is caused by excessive levels of
the neurotransmitter. It can be fatal. Symptoms include confusion, agitation,
dilated pupils, headache, rapid heart rate, and changes in blood pressure and
Product name: active
ingredient (trade) or product class
Potential signal of a serious
risk/new safety information
Additional information (as of
May 1, 2013)
Lack of therapeutic effect,
possibly related to product quality issues
FDA is continuing to evaluate
this issue to determine the need for any regulatory action.