Taking anti-vomiting drugs could more than triple your risk of a stoke, a study suggests.
The drugs, called antidopaminergic antiemetics, are often prescribed on the NHS to treat nausea due to conditions like migraines, or sickness resulting from cancer care.
But a study of more than 30,000 people prescribed three types of the drugs suggested users may have between a 2.5 and 3.5 times increased risk of a ischaemic stroke.
Ischaemic strokes are the most common type and occur when a blood clot blocks the flow of blood and oxygen to the brain.
The authors of the study, from Bordeaux University, suggested the drugs could be influencing the flow of blood in the brain and thereby increasing stroke risk.
Antidopaminergic antiemetics work by blocking the pleasure chemical dopamine, which is also involved in feeling nauseous, from activating in the brain.
French researchers have found people on antidopaminergic antiemetics which are prescribed to combat nausea were associated with a three times increased risk of a stroke (stock image)
WHAT IS A STROKE?
There are two kinds of stroke:
1. ISCHAEMIC STROKE
An isachemic stroke – which accounts for 80 percent of strokes – occurs when there is a blockage in a blood vessel that prevents blood from reaching part of the brain.
2. HEMORRHAGIC STROKE
The more rare, a hemorrhagic stroke, occurs when a blood vessel bursts, flooding part of the brain with too much blood while depriving other areas of adequate blood supply.
It can be the result of an AVM, or arteriovenous malformation (an abnormal cluster of blood vessels), in the brain.
Thirty percent of subarachnoid hemorrhage sufferers die before reaching the hospital. A further 25 percent die within 24 hours. And 40 percent of survivors die within a week.
Age, high blood pressure, smoking, obesity, sedentary lifestyle, diabetes, atrial fibrillation, family history, and history of a previous stroke or TIA are all risk factors for having a stroke.
SYMPTOMS OF A STROKE
- Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
- Sudden confusion, trouble speaking or understanding
- Sudden trouble seeing or blurred vision in one or both eyes
- Sudden trouble walking, dizziness, loss of balance or coordination
- Sudden severe headache with no known cause
Of the roughly three out of four people who survive a stroke, many will have life-long disabilities.
This includes difficulty walking, communicating, eating, and completing everyday tasks or chores.
Both are potentially fatal, and patients require surgery or a drug called tPA (tissue plasminogen activator) within three hours to save them.
Previous studies had found a link between antipsychotic medications, which work similarly, and stroke risk so the researchers wanted to explore if anti-nausea drugs were the same.
They looked at three types of medication – domperidone, metopimazine, and metoclopramide.
The researchers analysed French healthcare system data and found 2,612 patients who had suffered their first ischaemic stroke between 2012 and 2016 and had been prescribed one of the three anti-nausea drugs within 70 days of their stroke.
They then matched these patients to a healthy group of nearly 22,000 who did not have a stroke but had taken medications within the same timeframe.
When patients took the antidopaminergic antiemetics was also considered so researchers noted how long before a stroke people took one of the medications.
Publishing their findings in the BMJ, the researchers found the majority of stroke sufferers had their stroke within 14 days of taking the medication.
This increased risk stroke was observed across all three medications, but was highest in metopimazine with 3.6 times higher risk, and metoclopramide, with a 3.5 times higher risk.
The last of the three anti-nausea drugs, domperidone, had the least inflated risk at 2.5 times higher.
Lead author of the study, Anne Bénard-Laribière, a pharmacologist at Bordeaux University, said: ‘The higher risk found for drugs crossing the blood-brain barrier suggests a potential central effect, possibly through an action on cerebral blood flow.’
However, she added further research was needed to determine the exact reason being the increased stroke risk.
The study was limited by the healthcare database not recording the dosage of the anti-nausea drugs patients were prescribed meaning this aspect could be influencing the stroke risk observed.
More than 100,000 strokes happen every year in the UK, about one every five minutes. About 35,000 Britons die each year from strokes.
In the US, about 795,000 people have strokes annually and some 140,000 of them die – about one out of every 20 deaths is caused by stroke. I
Ischaemic stroke accounts for 80 per cent of strokes with the remainder being hemorrhagic.
Hemorrhagic strokes occur when a blood vessel bursts, flooding part of the brain with too much blood while depriving other areas of adequate blood supply.