Some products that might claim to be medical cannabis, such as “CBD oil” or hemp oil, are available to buy legally as food supplements from health stores. But there’s no guarantee these are of good quality or provide any health benefits.
Cannabis bought illegally off the street, where the quality, ingredients and strength are not known, is the most dangerous form to use.
Can I get a prescription for medical cannabis?
Currently, it is only likely to be prescribed for the following conditions:
They tend to only contain very small amounts of CBD, so it’s not clear what effect they would have.
Nabiximols (Sativex) is a cannabis-based medicine that is sprayed into the mouth.
Cannabis oils or concentrated extracts are obtained by the extraction of cannabinoids from the dried flowers (cannabis flos) of the cannabis plant. The purpose of producing cannabis oil is to make cannabinoids and other components (i.e. terpenes), available in a highly concentrated form.
Consequently, there is a significant need to standardise and control cannabis extracts and to regulate their distribution as potential medicinal products.
Oils are typically prepared for oral sublingual administration. They have become increasingly popular in recent years. This is because they are easy to use, compared to inhalation by vaporization. Prescribers and pharmacists are more familiar with oral dosing, which also promotes their use.
The preparation of cannabis oil or cannabis concentrates at home, or the use of unregulated cannabis oils or concentrates is not advised.
The pharmacist prepares medicinal cannabis oil at the Transvaal Pharmacy, the Netherlands
Four drugs based on cannabis compounds are already on the market in Europe. Among them are Nabilone, a synthetic compound that mimics THC, is prescribed for nausea and vomiting caused by chemotherapy, and Sativex, an oil that contains equal parts THC and CBD, is used to treat muscle spasms in multiple sclerosis. Both contain too much THC to administer to children. “The only medicines that are approved in the UK would get children stoned,” said David Nutt, professor of neuropsychopharmacology at Imperial College, London.
Cannabis oil can only be sold legally in Britain if it contains less than 0.05% THC. But the nation’s medicines regulator, the MHRA, announced recently that even pure CBD could not be sold as a medicine without first going through the usual clinical testing and safety checks required for all new medicines. This month, the US Food and Drug Administration will consider the approval of Epidiolex, a CBD-based medicine from GW Pharmaceuticals, which has completed such clinical trials. The European Medicines Agency (EMA) will rule on the drug early next year. If the EMA approves Epidiolex, it could be available to prescribe to named patients in Britain next year, Brexit notwithstanding.
CBD is an anticonvulsant, and some other compounds in the plant, including THC and cannabidivarin, may be too. There is good evidence from clinical trials in the US and Europe that pharmaceutical preparations of CBD can treat two severe forms of childhood epilepsy known as Dravet syndrome and Lennox-Gastaut syndrome. Both forms of epilepsy often fail to improve with existing epilepsy drugs. CBD is generally considered safe, but some trials have reported side effects including dry mouth, lightheadedness and altered liver enzyme activity.
Don’t we already have cannabis-based drugs?
Cannabis oils are extracts from cannabis plants. Unprocessed, they contain the same 100 or so active ingredients as the plants, but the balance of compounds depends on the specific plants the oil comes from. The two main active substances in cannabis plants are cannabidiol, or CBD, and delta-9 tetrahydrocannabinol, or THC. Oil extracted from hemp plants can contain a lot of CBD, while oil from skunk plants will contain far more THC. THC produces the high that recreational cannabis users seek, while oils for medical use contain mostly CBD.
Other forms of cannabis are solid and are usually sold either as resin or dried plant material. In commercially-produced medical cannabis oils, the concentrations of CBD and THC tend to be well-controlled, which makes it easy to calculate doses.
Europe is a patchwork of cannabis legislation. In the Netherlands, doctors can prescribe cannabis and cannabis preparations for symptoms caused by multiple sclerosis, HIV/AIDS, cancer, long-term pain and the tics associated with Tourette’s syndrome. Other European nations are following suit. In the US, at least 29 states allow medical uses of cannabis, and earlier this year, California became the eighth state to permit recreational use of the drug, too.