Down a dingy back alley in Beirut to an open garage for a meeting with an amphetamine dealer who is out on bail on terrorism charges, it's not your usual assignment, even for the Middle East, writes correspondent Matt Brown.

Lebanese drug dealer Abu Hamid (not his real name) has an important story to tell.

He is selling between 1,500 and 2,000 amphetamine pills in Beirut each month as the Syrian civil war drives a surge in drug manufacture and use.

Amphetamines marketed as Captagon, the little pill with a lot of punch, have made their mark far beyond Syria's frontlines.

Abu Hamid agrees with reports that made global headlines last year: Islamic State (IS) fighters are taking amphetamines to fuel their reign of terror. But the real story is much broader, much deeper and crosses the borders from Syria into Lebanon.

IS fighters are not the only ones getting high to get violent.

Abu Hamid says abuse of the drug is widespread among all Syrian factions.

"All fighters are taking it. They all have to take it. Maybe their leader, he doesn't take it so he can sleep and wake up as he wishes, but all the fighters take it to be able to go into combat," he says.

That makes sense, because soldiers have abused amphetamines since they were invented and it is a common thing in warfare, and in Syria the market has expanded dramatically.

Sorry, this video has expired Islamic State group fighters are using drugs while waging their fight, experts say

"The dealer who used to sell 1,000 pills is now selling 10,000 pills in Syria, even 20,000, and he's happy!" Abu Hamid says.

"And maybe he's not even producing as much as he could sell. It is widespread now."

Perhaps more importantly, the Syrian conflict has caused a dramatic shift in drug manufacturing from Syria into Lebanon.

"Lots of laboratories have relocated into Lebanon, they are not in Syria anymore," Abu Hamid says.

The Syrian conflict has seen drug labs move to Lebanon. ( ABC: Aaron Hollett )

Like much of Syria's infrastructure and legitimate manufacturing capacity, a lot of drug labs have been destroyed or forced to shut down.

For legitimate businesses, the war has been devastating. But when it comes to drugs, smugglers and dealers, where there's a war and a will, there's a way.

Lebanese police confirm there has been an explosion in the number of drug labs churning out unprecedented quantities of amphetamines for sale domestically, as well as for export back into Syria and to traditional markets in the Gulf states.

The evidence is piling up. In the basement of a Beirut police station I clamber over cases full of cocaine and boxes full of hashish to find a mini-mountain of amphetamine pills.

Police drug busts have escalated in an effort to dismantle the trade. ( ABC: Aaron Hollett )

Lebanese police say they have seized more than 80 million pills in the past three years.

Beirut Police General Ghassan Shamsedine says drug manufacturing activity has shifted from Syria into Lebanon.

"After 2013, we can say that it has changed. Sixty per cent is still produced in Syria and maybe 40 or 35 per cent is produced in Lebanon," he says.

Drug busts are through the roof. All factions of Lebanon's sectarian political system are now said to be involved in a lucrative trade that will not be easy to dismantle.