Doses of Captagon, an “amphetamine-type stimulant,” seized by French customs officials at the Roissy-Charles de Gaulle airport. (Douanes Francaises/AFP)

French authorities announced Tuesday that they have confiscated about 300 pounds of a drug known as Captagon this year. Officials said this marked the first time that the drug — infamous for its use by fighters in the Syrian war — has been discovered in the country.

According to French customs officials, 750,000 pills worth an estimated $1.7 million were found hidden in industrial molds being transported from Lebanon. Two separate discoveries of the pills were made in January and February at Charles de Gaulle airport, officials said, noting that the pills were remarkably well hidden and required industrial tools to find.

French officials say it is the first seizure of its kind in France.

The drug known as Captagon has been around for decades — the word “Captagon” itself is a former brand name that refers to the pharmaceutical drug fenethylline — but most countries gradually banned it due to its addictive qualities.

In the 1960s, fenethylline was widely recommended to people suffering from ailments like hyperactivity and narcolepsy. However, the United State classified fenethylline as a Schedule I drug under the federal Controlled Substances Act in 1981, according to the National Criminal Justice Reference Service. Most other countries made it illegal after 1986, when it was listed by the World Health Organization for international scheduling under the Convention on Psychotropic Substances.

While fenethylline died out in much of the world, Captagon appears to have lived on in the Middle East. Exactly what is now in it isn't always clear, however, and some experts doubt it has much link to fenethylline anymore — the United Nations Office on Drugs and Crime (UNODC) notes that pills marked with a Captagon logo tend to include amphetamine trafficked from Southeast Europe, although caffeine is often another ingredient.

As Syria descended into civil war, experts noted that production of Captagon surged in the country. The reason was twofold: Not only was the drug easy to produce and thus a relative easy line of income for militias and other groups, it also provided the euphoria, stamina and energy needed to keep fighters fighting. In a BBC Arabic documentary that aired in 2015, fighters described a feeling of invincibility when they took the drug.

“There was no fear anymore after I took Captagon,” one man said.

There has long been speculation that the drug was being used by large numbers of fighters for the Islamic State, an extremist group known internationally for its brutality. Given the large number of French citizens who have traveled to Syria to fight with the group, the presence of the drug in France may well cause widespread concern. In the aftermath of the horrific attacks in Paris on Nov. 13, 2015, that left 137 people dead, there were a number of reports that suggested that the attackers may have been taking Captagon, although such reports were later dismissed.

However, French customs officials noted that at least one of the shipments of Captagon they have seized was bound for the Czech Republic. After conducting an investigation with German and Czech authorities, French authorities now think “the cargo was actually destined for Saudi Arabia, passing through Turkey.” Use of the drug is believed to be widespread in the Saudi kingdom and predates the Syrian conflict — in 2010 and 2011, the UNODC found the country to have the highest number of amphetamine seizures, most of which was Captagon.

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