How Safe is CBD?

Over the last 10 years, there has been a rapid cultural change. Medicial use of cannabis has become more accepted. Cannabidiol is a component of cannabis that does not have the same effects on the brain as the psychoactive part of the plant. It's become popular as aherbal supplement. Most city streets have signs advertisingCannabidiol. The popularity of cannabidiol might be premature.

Herbal supplements are not supplements and the fact that they are herbal is unimportant. By any reasonable definition they are drugs. There are two systems for selling drugs in the US. Drugs go through a research protocol where they are tested for safety and efficacy. Drug-drug interactions are studied and side effects are tracked. Most drugs don't make it through this process, and those that do come with a description of their pharmacological profile are the ones that do. Drugs are classified based on their potential for harm. They are not risk free, but at least there is a transparent process to minimize harm and maximize the benefit to risk ratio.

Drugs can be sold directly to the consumer in the parallel drug market without any need for a previous study. They can be sold in combination with other ingredients without any information about their safety or efficacy. They have high levels of substitution and adulteration. Even when pure, there is no way to know the risks and benefits of their use. Most products in this category have low levels of absorption, which reduces the potential for harm and benefits.

There are two categories of drugs called herbal supplements. General use is considered an adequate evidence of safety and no mind is given to claims of efficacy. The only condition is that sellers can't make disease claims, but this is easy to ignore.

Another interesting chemical isCannabidiol. It is possible that it is a useful drug. Preliminary evidence shows that it can be useful in treating anxiety and other mood disorders. Epidiolex was approved by the FDA as a prescription drug for certain types of sphenoid disorders. It is odd that a drug is available in two different forms.

The lack of regulations for herbal drugs is shown by the dual life ofCannabidiol. The main justification is that herbs are naturally occurring. There is no reason to think that being "natural" in any way means safety. Natural poisons are the most lethal on the planet.

We have a long history of safety because of herbal supplements. Multiple levels of flawed reasoning is what this is. Anecdotal evidence will only tell you about the immediate effects. Information about statistical risks, complex interactions, rare but deadly side effects, and subtle effects such as organ toxicity won't be provided. Many herbal products don't have long histories of traditional use. It's more of a marketing tool. Traditional use can't be compared to scientific evidence.

There is an FDA approved form ofCannabidiol, which we can't assume has identity risks of every herbal version out there, but gives us some information on safety. Any drug that is active enough to have a benefit is likely to have risks and interactions. It turns out that the safety profile of cannabidiol is similar to that of a prescription drug, but it is worse.

There is a review for the year 2019.

Nearly one-half of CBD users experienced [adverse drug events, ADEs], which displayed a general dose-response relationship. Common ADEs include transaminase elevations, sedation, sleep disturbances, infection, and anemia.

Anemia can mean bone marrow suppression and tranaminase elevations can mean effects on theLiver. Side effects can show organ toxicity. Controled trials are limited in their ability to detect rarer side effects. Drugs are monitored after they are on the market because they tend to come out only when the drug is being used. A recent case report shows a patient who had a severe cardiac reaction to herbalCannabidiol. She had longQT intervals that had an adverse effect on the heart's electrical activity. A life threatening cardiac arrhythmia was caused by this. The abnormal rhythm was fixed when she stopped taking the supplement.

In this case, the patient was taking high doses ofCannabidiol without a prescription, without any physician advice or supervision, and was lulled into a false sense of safety becauseCannabidiol is a "natural herb"

Drug-drug interactions have a high potential forCannabidiol. Increasing or decreasing the effective blood level is what this means. This is the same review that was found in 2019.

Given CBD effects on common biological targets implicated in drug metabolism (e.g., CYP3A4/2C19) and excretion (e.g., P-glycoprotein), the potential for DDIs with commonly used medication is high.

The potential ofCBD is high compared to other drugs. Taking cannabidiol without supervision can result in a potential that it can affect other medications.

It behaves like a drug and is not a clean one. The reviewers came to a conclusion.

General clinical recommendations of reducing substrate doses, monitoring for ADEs, and finding alternative therapy should be considered, especially in medically complex patients. CBD is implicated as both a victim and perpetrator of DDIs and has its own ADE profile. These effects should be considered in the risk-benefit assessment of CBD therapy and patients and consumers made aware of potential safety issues with CBD use.

It can't happen if consumers are taking products over the counter without any supervision and that they think they are safe. I'm not against the drug itself. There is a false dichotomy between drugs and supplements. Cannabidiol should be studied and regulated the same as any other drug.

• Steven Novella is the founder and currently Executive Editor of Science-Based Medicine. The Great Courses and The Skeptics Guide to the Universe were both written by Dr. Novella.

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