'Marijuana refugees' give cannabis to epileptic children
7 May 2014 Last updated at 01:32 BST
Parents in the US with severely epileptic children are turning to marijuana for treatment.
Oil produced from a strain of the plant, which doesn't make the children high, appears to be having a dramatic effect on reducing seizures. It's being produced in Colorado, one of the two US states which has legalised cannabis.
Although not scientifically proven, families think it's making a big difference - and a British pharmaceutical company is trialling a new epilepsy drug based on cannabis extract, which has been approved by the US Federal Drug Administration.
The BBC's Alastair Leithead reports.
Filmed and edited by the BBC's Luke Winsbury
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