"This approval serves as a reminder that advancing sound development programs that properly evaluate active ingredients contained in marijuana can lead to important medical therapies".
CBD oil is now sold online and in specialty shops across the US, though its legal status remains murky.
While most hemp-derived CBD companies are rapidly growing their businesses without repercussion or worry, many cannabis CBD businesses are hesitant about selling products in states where marijuana is not yet legal.
Gover said the approval signals "validation of the science of cannabinoid medication".
Nasdaq-listed GW Pharmaceuticals, which grows its own marijuana plants in glass houses in Britain, hopes the drug will be approved in the United Kingdom next year. Cannabidiol would still be considered a controlled substance, but it would be permitted for legal medical use under certain circumstances.
Still, Jackson is glad that her family's experience could now provide new treatment options for other childhood seizure sufferers.
A company representative said the list price for the medication had not been set yet.
In the meantime, it is possible that once on the market, Epidiolex could be prescribed for conditions other than the ones it's approved for.
The FDA previously cleared medications containing synthetic versions of THC for nausea for patients getting chemotherapy and for other uses, but it had not approved any drug derived from the plant itself.More news: North Korea skips annual 'anti-US imperialism' rally
The FDA notes that it will still "take action" against illegal CBD products making "serious, unproven medical claims".
Patients, parents of children suffering from severe epilepsy, and some researchers have long suspected CBD's potential to treat the devastating seizure disorders.
Epidiolex was approved for patients age 2 and older who suffer from Lennox-Gastaut and Dravet syndromes.
For their part, GW Pharmaceuticals executives say they are not trying to disrupt products already on the market. "Because of the adequate and well-controlled clinical studies that supported this approval, prescribers can have confidence in the drug's uniform strength and consistent delivery".
Despite increasing acceptance, there is little rigorous research on the benefits and harms of marijuana. The administration would then presumably reclassify cannabidiol in a less restrictive schedule (the DEA has five drug schedules, with Schedule I being the most restrictive and Schedule V being the least restrictive).
Still, this approval comes as the White House is said to be reconsidering federal prohibition of marijuana and as more and more states approve it for recreational and medicinal use. A study at the end of previous year found that almost 70 percent of CBD products sold online were mislabeled. The decision caps decades of work by the company to gain approval in the US for a medicine derived from the cannabis plant.
Epidiolex was recommended for approval by an advisory committee in April, and the agency had until this week to make a decision.
The European Medicines Agency is expected to rule on the therapy in early 2019.