The first prescription drug made from marijuana is now available for prescription in all 50 states - a milestone that could spur more research into a drug that remains illegal under federal law.
In June, the Food and Drug Administration approved the twice-daily oral medication, Epidiolex, to treat two rare forms of epilepsy that begin in childhood.
Today, the drug became available for prescription.
The move was hailed by the medical marijuana industry as a sign of acceptance - though Epidiolex is not quite medical marijuana.
The strawberry-flavored syrup is a purified form of a chemical ingredient found in the cannabis plant - but not the one that gets users high. It's not yet clear why the ingredient, called cannabidiol, or CBD, reduces seizures in some people with epilepsy.
Epidiolex is now available in all 50 states. GW Pharmaceuticals studied the drug in more than 500 children and adults with hard-to-treat seizures, overcoming numerous legal hurdles that have long stymied research into cannabis
'Because these patients have historically not responded well to available seizure medications, there has been a dire need for new therapies that aim to reduce the frequency and impact of seizures,' said Justin Gover, CEO of Epidiolex manufacturer, the British firm GW Pharmaceuticals.
'We are committed to ensuring that these patients can access this novel cannabinoid medicine that has been thoroughly studied in clinical trials, manufactured to assure quality and consistency, and is eligible to be covered by insurance for appropriate patients.'
GW Pharmaceuticals studied the drug in more than 500 children and adults with hard-to-treat seizures, overcoming numerous legal hurdles that have long stymied research into cannabis.
FDA officials said the drug reduced seizures when combined with older epilepsy drugs.
The FDA has previously approved synthetic versions of another cannabis ingredient for medical use, including severe weight loss in patients with HIV.
Epidiolex is essentially a pharmaceutical-grade version CBD oil, which some parents already use to treat children with epilepsy. CBD is one of more than 100 chemicals found in marijuana. But it doesn't contain THC, the ingredient that gives marijuana its mind-altering effect.
Physicians say it's important to have a consistent, government-regulated version.
'I'm really happy we have a product that will be much cleaner and one that I know what it is,' said Dr Ellaine Wirrell, director of the Mayo Clinic's program for childhood epilepsy. 'In the artisanal products there's often a huge variation in doses from bottle to bottle depending on where you get it.'
Side effects with the drug include diarrhea, vomiting, fatigue and sleep problems.
Several years ago, Allison Hendershot considered relocating her family to Colorado, one of the first states to legalize marijuana and home to a large network of CBD producers and providers. Her 13-year-old daughter, Molly, has suffered from severe seizures since she was 4 months old. But then Hendershot learned about a trial of Epidiolex at New York University.
'I preferred this to some of those other options because it's is a commercial product that