Efficacy of popular period pain drug Spasfon questioned in France

The effectiveness of a popular drug used in France for period and stomach pain is being questioned after a specialist queried its scientific basis in a new book.

Spasfon is a popular anti-spasm (antispasmodic) medication, of which 25 million boxes were prescribed in France in 2021.

However medicine philosophy specialist, Juliette Ferry-Danini, has questioned its effectiveness and scientific basis in her new book Pilules Roses, de l’ignorance en médecine (‘Pink pills: Ignorance in medicine’), saying there is a lack of reliable data.

Vidal, the French medicine dictionary, states that Spasfon “combats abnormal and painful contractions of the intestines, bile ducts, urinary tract and uterus”.

It was first reviewed by the l'Agence nationale de sécurité du médicament in 1963, and marketed to the public after clinical trials. It is partially reimbursed by the state in France.

But Ms Ferry-Danini told Libération that the basis of the scientific trials was less than rigorous.

She said: “They gave the drug to around 15 people and observed if it worked. The worst thing was that they were originally testing it for bladder and urinary tract pain but in the process, they ended up giving it to nine women who were menstruating. No further work was done on this aspect.”

‘Low medical services rendered’

The French health authority Haute autorité de santé (HAS) admitted in 2017 that the “medical service rendered remains low” for the treatment of “functional disorders of the digestive tract, acute urinary tract pain” and painful periods.

‘Medical service rendered’ is an official measurement - le service médical rendu (SMR) - used by public health authorities to measure whether a drug should be considered effective for public health, and reimbursed.

The French health authority HAS also said that the SMR was considered to be “insufficient” for the “symptomatic treatment of pain associated with functional disorders of the bile ducts”. As a result, reimbursement was removed for the treatment of biliary pain. Another study in 2018 found similar results.

Why then is the medicine used?

This could be explained by the fact that 60 years ago when the medicine was first approved, thresholds for marketing drugs were lower.

Laurent Beaugerie, head of the gastroenterology and nutrition department at Saint-Antoine hospital in Paris, said that the ‘absence of proof’ does not “necessarily mean that the product is [completely] ineffective”. He said that some people are “convinced that it works”, and said it could be due to a placebo effect. He said that he does not believe it is medically effective.

He added that while authorisations for drugs can be withdrawn, they are usually only taken off the market if patients report negative effects. This has not happened with this drug, he said.

Spasfon ‘safe and effective’, says lab

Spasfon is marketed by the laboratory Teva Pharmaceutical Industries.

In a statement it told BFMTV that Spasfon had been used safely “for almost 60 years in gastroenterology, urology and gynaecology” and said that “knowledge of the efficacy of these drugs on spasms of various origins is based on several decades of use in clinical research”.

This “attests to the effectiveness and safety of the drug”, it said.

It also said that the drug had been judged to have a ‘positive benefit/risk ratio’ in the latest risk assessment from the drug safety committee le Comité d'évaluation des risques en matière de pharmacovigilance.

This means that the risk of taking the drug is considered justified compared to the condition it is aiming to treat.

However, Ms Ferry-Danini has said that the continued prescription of the pills conceals a “sexist issue at the crossroads of health and marketing”, and said that the drug has been “overwhelmingly prescribed to women… despite the poor scientific data”.

Sexist overtones?

Data from the HAS shows that in 2016 10% of the prescriptions for Spasfon were for painful periods - making it the second-most common reason for its use, behind gastroenteritis - despite the lack of evidence that it works.

Ms Ferry-Danini believes that “sexism was an undeniable driving force behind this success, which should not have happened. The worst thing is that no one ever listened to the women who spoke out about this drug”, she said.

She also said that the very existence of the product is based on sexist overtones, and comes from the idea that “women are biliary” and that period pain is a form of ‘female hysteria’.

This was a common theory that persisted for centuries pre-1900, in which doctors believed that women’s wombs (‘hystera’ in Greek) moved around their body, causing “hysteria”.

Teva did not comment on this point.

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