Two years ago, the mother of a patient suffering from schizophrenia and cannabis addiction was desperately searching for cannabis rich in Cannabidiol (CBD). He knew that one of the components of cannabis, Tetra-hydro-cannabinol (THC), worsened the psychosis that affected his son and he had read that CBD could have a certain protective effect.
The only information we were able to give you was that, according to our research, the marijuana sold in Barcelona in 2017 had 7 mg of THC and 3 mg of CBD per cigarette. In contrast, the circulating hash had only traces of CBD and 7 mg of THC.
Surely that mother will be happy that the United Nations Commission on Narcotics has recently decided to reclassify cannabis derivatives. That reclassification does not legalize cannabis, but it does facilitate medical research on the potential therapeutic effects of CBD. In recent years, there have been multiple studies (not always rigorous) suggesting possible therapeutic applications of CBD.
It is no coincidence that the popularity of CBD goes hand in hand with the progressive legalization of cannabis in the Western world. In all ‘legal’ drugs (such as alcohol or tobacco) there is a marketing interested in exalting their supposed benefits, often with little scientific basis.
By way of example, resveratrol is an antioxidant present in red wine whose beneficial effects have been extolled ad nauseam. But it has not been mentioned that to take an effective dose of this substance we should drink until we reach an ethyl coma.
Cannabis is a plant with more than 2,500 varieties. In its composition we find more than 500 compounds and among them, more than 100 cannabinoids. Here we find THC, the main responsible for neurotoxicity, and CBD, which we will analyze in more detail in the following lines.
What is CBD
CBD is a cannabinoid very similar to THC, but without psychotropic properties. Its side effects include diarrhea, lack of appetite, drowsiness and sedation, although the latter are probably related to drug interactions with medication.
One of the proven therapeutic effects of CBD is in the treatment of especially difficult forms of childhood epilepsy. A recent meta-analysis with a sample of 550 children showed that those on CBD treatment had 20% fewer seizures. These results cannot be generalized to all types of epilepsies and not even to all types of seizures in childhood.
There are at least three more areas where the potential utility of CBD is being explored, although the evidence is less consistent: chronic pain, mental health, and neoplasms. We will review them below.
Therapeutic uses of CBD
The use of cannabis to relieve pain has been advocated since ancient times. However, scientific data shows that it is not the best therapeutic alternative when we weigh pros and cons.
One of the problems in evaluating the efficacy of CBD in treating pain is that most studies use preparations containing CBD and THC in identical proportions, with the risks of toxicity that this entails.
The data available to date is surprising. In well-designed studies, CBD has shown effectiveness in controlling pain in fibromyalgia, kidney transplantation, multiple sclerosis, and spinal cord injury. Instead, the results have been negative for Crohn’s disease and chronic widespread pain.
In the field of mental health, the use of CBD has been promoted for the treatment of depressive and mood disorders, as well as in the treatment of addictions.
Unfortunately, the systematic reviews published in the last two years conclude that there is no consistent evidence to justify its use in conditions such as depression, bipolar disorder and schizophrenia. An interesting aspect, but still little studied, is its possible use in the treatment of cannabis addiction.
Finally, CBD is also being studied as a possible antineoplastic agent, although in this case the investigations are at more preliminary levels and there is no proven evidence in humans.
In the laboratory, however, a positive effect of CBD has been observed in cell cultures of liver, prostate and breast cancer, although the mechanisms of action have yet to be confirmed and its transfer to the clinic does not seem close.
Although, as we have just seen, the scientific evidence on the alleged benefits of CBD is rather limited, this has not been an obstacle to its popularity growing enormously in recent years. Explaining this phenomenon is also important.
Why is CBD getting popular?
To understand the good press that CBD enjoys, it is necessary to analyze the social and economic circumstances linked to the cannabis business. In the process of progressive normalization of the use of cannabis derivatives in the Western world, the actors who aspire to obtain a great economic benefit in this new framework play an important role.
The cannabis industry has been trying for years to improve the social perception of marijuana. The presence in their products of a non-addictive substance with a therapeutic potential constitutes a powerful marketing weapon. And they don’t forget to make the most of it.
CBD is now being sold in body creams, serums and soft drinks and is “flooding”, in the words of Isabella Kwai, the wellness industry. To the point that it is estimated that by 2025 its turnover in the United States will reach 16 billion dollars.
As with alcohol – and it happened before with tobacco – the loudspeakers for disseminating information about the supposed beneficial effects of cannabis are more powerful than those that warn about its risks.
Not all that glitters is gold
If we remove ourselves from this pressure and focus on what we really know, CBD is a promising substance, with few side effects, and that can be useful in the treatment of some diseases.
In the same way that recognizing morphine as a very useful drug does not mean validating the use of heroin, the therapeutic usefulness of CBD should not imply a change of position compared to cannabis derivatives in general.
We must not forget that when marijuana or other cannabis derivatives are consumed, in addition to CBD, other cannabinoids with widely demonstrated neurotoxicity are consumed.
CBD products under review
Going back to the beginning of the article, when the patient’s mother was searching for CBD in the market, she hardly knew what she was going to find. Being a product without sanitary approval, there is little quality control with the consequent discrepancy between the label and the actual content.
For example, the American Food and Drug Administration (FDA) found that many products sold as CBD contain little or no CBD.
In the Netherlands, 3 years ago, 8 products labeled as CBD were analyzed and, of these, only 4 presented a variability of less than 10% between what the label put and what it really was. One of them even contained 98% less CBD than advertised.
Although it is not usual, you can also find products that contain THC in amounts higher than recommended or even include synthetic cannabinoids that are much more powerful than THC.
In short, knowing the dose of CBD that you are really taking can be a challenge and a real complication if what you want to do is a treatment. The only exception is the drug approved by the Spanish Agency for Medicines and Health Products for the treatment of refractory epilepsy in children.
Antoni Gual Solé, Research Professor, University of Barcelona and Hugo López Pelayo, Specialist in Psychiatry and Clinical Researcher, August Pi Sunyer Biomedical Research Institute – Hospital Clínic Barcelona / IDIBAPS
This article was originally published in The Conversation. Read the original.
