Drugs to treat nausea and vomiting raise clotting risk

LONDON - Common drugs to treat nausea and vomiting increase the risk of deadly blood clots by a third, say researchers.

Hundreds of thousands of people in England take the new atypical antipsychotics, mainly for schizophrenia, but they are also used to treat common complaints like nausea, vomiting and vertigo.

Researchers said the drugs should be used more cautiously after findings from a study of more than 100,000 people detected they were associated with an increased risk of blood clots, according to the British Medical Journal.

The use of antipsychotics is controversial as evidence shows that their effectiveness is limited, and charities have warned they are used as a “chemical cosh” to subdue difficult elderly patients with dementia, reports the Telegraph.

Around 7.2 million prescriptions were dispensed for antipsychotics in England last year, including the newer atypical drugs examined in the study.

The team from the University of Nottingham investigated around 25,000 people who had suffered a blood clot, either in the legs or in the lung, and compared them with similar people who had not suffered one.

They found around three quarters of the people studied had taken prochlorperazine which is widely used to treat vertigo, nausea and vomiting. It is not effective at treating travel or motion sickness.

The results showed that those prescribed antipsychotics in the previous two years were 32 percent more likely to have had a blood clot. The more prescriptions a person had received the greater their risk of a clot.

People who had started taking the drugs in the previous three months were at even higher risk of clots, and were twice as likely to have had one than those not on the drugs.

Lead author Julia Hippisley-Cox at the University of Nottingham, wrote: “If other studies replicate these findings, antipsychotic drugs should be used more cautiously for nausea and agitation etc.”