The Spanish Health Ministry has issued a warning regarding the misuse of metamizole, a painkiller whose most popular brand name in Spain is Nolotil.
Following reports of British citizens who died after being prescribed the medication in Spain, the country’s health authorities are reminding users about the risk of a dangerous and unpredictable side effect known as agranulocytosis, which drastically lowers the patient’s white cell count and can even lead to death.
We found to our surprise that the agranulocytosis rate was nearly three time higher among foreigners than among Spaniards
Vicente Faus, Costa del Sol Hospital
On October 30, the Spanish Medication and Health Products Agency (AEMPS) issued a reminder that metamizole can only be purchased with a doctor’s prescription, even though many Spanish pharmacies continue to sell it over the counter.
Last weekend, British news outlets reported that a dozen UK citizens had died after taking metamizole in Spain. It is one of the most commonly prescribed anti-inflammatory medications in Spain and Latin America, although it is banned in several European countries, including Sweden, the UK and Ireland.
“The AEMPS has reviewed the situation in Spain due to recent reports of agranulocytosis filed with the Spanish Pharmaceutical Monitoring System, particularly in patients of British origin,” said the note. “While there has been a years-long debate around a greater sensitivity among the population of northern Europe, and certain genetic factors have been studied, available information does not allow us to either rule out or confirm a greater risk for groups with specific ethnic characteristics.”
But the AEMPS insists that the drug should only be taken for “short-term treatments, seven days at the most.” If a longer course is necessary, the agency encourages periodic blood tests to monitor the patients’ white cell count, and recommends “not using metamizole on patients when it is not possible to conduct these checks,” such as tourists.
The warning also calls for “special precaution with patients of advanced age” because they tend to have lower defenses than the general population.
The agency notes that there has been a rise in reports of adverse effects running parallel to a spike in metamizole consumption in Spain. “The use of metamizole in Spain, based on prescription information from the National Healthcare System, has doubled in the last 10 years, with the biggest rise observed in the last five years,” says the statement.
The people most at risk of agranulocytosis are the elderly and those with depressed immune systems. “It occurs randomly, meaning that it does not depend on dosage, and each person can react differently to it,” explains Pedro J. Ibor, coordinator of the Pain Management Working Group at the Spanish Society of Primary Care Physicians (Semergen).
Available information does not allow us to either rule out or confirm a greater risk for groups with specific ethnic characteristics
And while there are no conclusive studies to prove it, many health specialists suspect that people from northern Europe may be more sensitive to metamizole than Spaniards.
For over a decade, the scientific literature has been describing cases of agranulocytosis in tourists from northern Europe who took the medication in Spain or Latin America. The oldest case that this newspaper has had access to dates back to 2002 and analyzes the adverse effects suffered by Swedish patients who were prescribed metamizole in Brazil. The drug was banned in Sweden in 1974.
In Spain, health professionals at Costa del Sol Hospital in Marbella published a study on the subject in 2009. Nearly 30% of the hospital’s activity involves patients from northern Europe who are either visiting the area or are residents.
“We ran into this randomly,” explains Vicente Faus, who co-wrote the study when he was head of pharmacology at the health center. “The hospital had a computer system that allowed us to explore the agranalucytosis cases we had seen. We analyzed the connection with metamizole, and found to our surprise that the rate was nearly three times higher among foreigners than among Spaniards,” he recalls.
The study concluded that “agranulocytosis from metamizole is an adverse effect that occurs more frequently among British patients, and its use must thus be avoided.” Faus underscores that theirs was “a preliminary recommendation in anticipation of further studies.”
A spokesman for Boehringer Ingelheim, the maker of Nolotil – although there are many generic brands as well – said that agranulocytosis is a rare adverse effect that only occurs in one out of 1,000 to 10,000 patients. “We are working closely with the AEMPS to provide information about the effectiveness and safety of this drug.”
English version by Susana Urra.