It has been banned in Britain for decades due to safety fears.
Even in countries where metamizole is still available, it is only provided with a doctor’s prescription due to its possible side effects.
Yet outraged campaigners say rules designed to keep patients safe in countries where metamizole is available are being flouted, meaning Britons can still buy the painkiller over the counter in Spain for just £4.
This week, attention was drawn to the dangers of the little-known drug following the death of a British expat living in Spain.
Mark Brooks, originally from Derbyshire, was playing golf near his home in Alicante in October when he started experiencing shoulder pain.
Father-of-one Mark Brooks from Derbyshire is believed to be the drug’s latest victim
Mr Brooks’ death is the latest in a series of deaths in Spain linked to the drug. Nolotil is banned in more than 30 countries, including Britain
The father-of-one, 42, went to his local health clinic where he is believed to have been given Nolotil, the branded version of the drug.
Four days later the gardener was dead, believed to be the last victim of the drug.
Mark’s death is one of 40 British fatalities in Spain that campaigners have linked to the use of metamizole.
Others include those of husband and wife Gloria and Alan Robson, both in their 80s, with their son blaming their deaths on the Nolotil they were prescribed while on holiday in 2017.
A year later, Lorna Vincent, 75, a British expat living in Spain, died after being given the painkiller following surgery in hospital, while her family believed the two were related.
Another British holidaymaker, William Smith, 66, also died in Torrevieja in February 2016 after developing sepsis as a result of taking a five-day Nolotil treatment.
However, there is no concrete evidence yet that the drug is responsible for many of the reported deaths, but families suspect a link.
Most Britons have never heard of metamizole as it has been banned in Britain since international safety concerns arose in the 1960s and 1970s.
But it is the painkiller of choice for doctors in countries such as Spain, where many doctors work with the expression ‘Nolotil for pain’.
In theory, metamizole, which can come in the form of tablets or injections, is only available by prescription in Spain, meaning it should only be dispensed after consulting a doctor.
But there are reports from the field that this is not being enforced.
Spanish medics have also been told by the country’s regulators since 2018 not to prescribe the drug to British tourists.
The guidance emerged after an unpublished study found that Britons have an ’80 to 120 times higher’ risk of agranulocytosis compared to Spanish patients.
The rare side effect occurs when the number of white blood cells, which are crucial in helping the body prevent and fight dangerous infections, collapses. This can lead to potentially fatal sepsis and organ failure.
Gloria and Alan Robson’s family claim they died after taking Nolotil in Spain
Lorna Vincent, left, with her daughter Kim Glasby. Lorna died of multi-organ failure in April 2018 after receiving metamizole following surgery in Spain
Even survivors can suffer lifelong injuries from the complications, including amputations.
However, rigorous scientific analysis of this specific issue has yet to be conducted and experts say further work is needed to confirm the findings.
Estimates of the risk of developing agranulocytosis from taking metamizole vary, but previous studies have calculated this at around 0.6-0.7 percent, or seven in 1,000 patients.
There is also a rare risk of an allergic reaction to metamizole, similar to other medications.
Campaign groups, such as the Association for Drug Affected People (ADAF), have called for greater awareness of the dangers of Nolotil for tourists in Spain.
The group’s president, Cristina Garcia del Campo, told MailOnline: ‘Something has to be done or people will continue to die.’
Del Campo claims the recommendation to stop handing out the drugs to Britons in 2018 did not work and they are often given them without being aware of the potential increased risk.
The campaigner has now filed a negligence complaint with the Spanish public prosecutor, claiming it is a matter of ‘human rights’.
She claims that in many cases Nolotil is not listed in patients’ medical records because doctors use it so often.
The ADAF criminal file asks: ‘What happens in Spain if the product is banned in countries such as Great Britain, the United States and Ireland, to name just three of more than forty examples, because it is very dangerous?’
The filing mentions the “crime of gross negligence affecting public administration officials,” claiming that “the negligent actions of these officials are currently causing harm and even deaths.”
It says the “people responsible for patient safety…are not doing their jobs responsibly.”
The document also calls on Spanish health officials to “urgently conduct a thorough investigation into the matter.”
Del Campo has vowed not to give up her fight to protect people from the drug’s potentially deadly effects, saying: “More and more people will die unless something is done immediately.”
Brits looking for the Spanish sun aren’t the only ones at risk of getting metamizole on a European holiday.
The painkiller is available in many other favorite European holiday destinations, including Portugal, Italy, Belgium and Germany.
Metamizole is also commonly sold, sometimes without a prescription, in developing countries, especially in Mexico and South America.
Britain isn’t alone in banning the drug; forty other countries, including the US, Canada and Australia, also ban doctors from dispensing the drug due to safety concerns.
A spokesperson for Boehringer Ingelheim, the manufacturer that makes Nolotil, said in a statement: ‘We take patient safety and public health seriously and work closely with regulators on product safety-related issues.
‘We believe that the current approved prescribing information adequately reflects current knowledge of identified risks.’