ISIS fighters are being fuelled by a cheap amphetamine-like drug which can keep soldiers on their feet for days.

‘Captagon’ - which is actually scientifically known as fenethylline - is a banned drug which is popular in the Middle East and is now thought to be being produced on a large scale in Syria, and used by several groups in the civil war.

View photos ‘Captagon’ - which is actually scientifically known as fenethylline - is a banned drug which is popular in the Middle East and is now thought to be being produced on a large scale in Syria, and used by several groups in the civil war. More

Trade in the drug is thought to bring millions into Syria and possibly to finance weapons and ammunition for groups such as ISIS.

The drug was used to treat conditions such as hyperactivity in the West but has been banned in most countries since the Eighties.

It is easy to make using basic knowledge of chemistry and can be made from legally available chemicals. It’s effects make users feel ‘superhuman’, according to the Washington Post.

"You're talkative, you don't sleep, you don't eat, you're energetic," Lebanese psychiatrist Ramzi Haddad told The Guardian.

View photos Trade in the drug is thought to bring millions into Syria and possibly to finance weapons and ammunition for groups such as ISIS. More

A Syrian police officer in Homs told Reuters he had witnessed its effects on anti-government protesters.

"We would beat them, and they wouldn't feel the pain," he said.

"Many of them would laugh while we were dealing them heavy blows.

"We would leave the prisoners for about 48 hours without questioning them while the effects of Captagon wore off, and then interrogation would become easier."

View photos Turkish soldiers in a tank observe the Syrian town of Ain al-Arab, known as Kobane by the Kurds, from a hill at the Turkish-Syrian border, in the southeastern Turkish village of Mursitpinar, Sanliurfa province. Photo: AFP More

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