“Marijuana in its natural form is one of the safest therapeutically active substances known to man. By any measure of rational analysis marijuana can be safely used within the supervised routine of medical care.”
—Francis L. Young at the 1988 ruling in the matter of “Marijuana Rescheduling Petition”
Is CBD safe? The answer to that is yes! Aside from the long list of medical applications and conditions CBD can help treat, another reason CBD has proven to be so powerful in the medical arena is that it is very safe.
Studies and scientific reviews confirm CBD’s safety: In a 2017 review, CBD’s safety profile was confirmed and even expanded.23 Not only that, but CBD was confirmed by the World Health Organization (WHO) in a 2017 report to pose no public health risk or potential for abuse. The WHO report deemed CBD to be very safe and well-tolerated across a wide spectrum of dosages. In 2011, a review found that long-term doses of up to 1,500 milligrams per day were well-tolerated in humans.1
In 2018, a WHO committee called for more scientific evidence and further review of CBD in response to the increase in interest from Member States in the use of cannabis for medical indications, including for palliative care, or specialized medical care for people with life-limiting illness. To that end, the Expert Committee on Drug Dependence (ECDD) did an initial review of CBD, and concluded:
“Recent evidence from animal and human studies shows that its use could have some therapeutic value for seizures due to epilepsy and related conditions. Current evidence also shows that cannabidiol is not likely to be abused or create dependence as for other cannabinoids (such as tetrahydrocannabinol (THC), for instance). The ECDD, therefore, concluded that current information does not justify scheduling of cannabidiol and postponed a fuller review of cannabidiol preparations to May 2018, when the committee will undertake a comprehensive review of cannabis and cannabis-related substances.”
Despite the intention to conduct a comprehensive review, when the ECDD met in June 2018 they conducted a more limited “pre-review.” The results of the pre-review were favorable, concluding that cannabis has therapeutic potential for conditions like chronic pain, appetite stimulation, epilepsy, opioid withdrawal, PTSD, and sleep disorders. They underscored that more robust clinical research and evidence is needed before they make a final determination on the efficacy of cannabis therapeutics for these conditions. They will submit the findings of their pre-review to the WHO, along with a recommendation that an in-depth review be carried out.
Cannabidiol’s nonaddictive properties are particularly provocative when considering the severe side effects and high rates of abuse with other prescription drugs, particularly opioids. According to the CDC, there were 32,445 opioid overdose deaths in America in 2016, about 89 per day. The National Cancer Institute states, “Because cannabinoid receptors, unlike opioid receptors, are not located in the brain stem areas controlling respiration, lethal overdoses from cannabis and cannabinoids do not occur.”
Another plus for cannabis therapeutics, and where CBD really shines, is in its ability to deliver a one-two punch when it comes to opioid use: not only can CBD treat pain, but it might also help lessen the cravings for and withdrawal symptoms associated with opioid addiction.
Cannabis and opioids are “co-agonists,” meaning they enhance each other’s effectiveness, and many people using cannabis in conjunction with opioids are either able to reduce their dosages or replace the opioids altogether. A survey of 984 patients who use opioids states, “97% percent of the sample ‘strongly agreed/agreed’ that they are able to decrease the amount of opiates they consume when they also use cannabis, and 81% ‘strongly agreed/agreed’ that taking cannabis by itself was more effective at treating their condition than taking cannabis with opioids. Results were similar for those using cannabis with nonopioid-based pain medications.”2
In a 2016 survey of opioid users with chronic pain, 64% reported a decreased use of opioids when adding cannabis to their treatment regimen.3 A first-of-its-kind, 18-month study will examine whether cannabis decreases the use of opioids in patients suffering from chronic pain at New York’s Albert Einstein College of Medicine, while a recent animal study showed that rats treated with CBD gel were less likely to relapse to opioid use.4
CBD is already being used to enhance the effects of antiepileptic drugs, often decreasing the dosage (along with reducing unpleasant side effects) or replacing them altogether. In the future, CBD might also become a useful addition to treatment regimens including prescription medications like antidepressant, antipsychotic, and anti-anxiety drugs.
The science supporting CBD has been widely accepted: CBD is safe and well-tolerated. It is all-natural, nontoxic, and non-addictive, and when compared to the side effects and safety profiles of traditional prescription medications, it’s no contest.
But other adverse effects (or no effects at all) can arise when it comes to the source, extraction methods, and manufacturing of CBD products.
Possible Side Effects
While there hasn’t been a lot of scientific study looking at the side effects of CBD, we do know for sure that impairment is definitely not one. In fact, studies show that CBD produces no impairment even at very high doses.
A 2017 scientific review shows that most clinical studies have focused on CBD treatment for epilepsy and psychotic disorders, and in these areas, the most common patient side effects included tiredness, diarrhea, and changes of appetite/weight.5
Anecdotally, the most common side effects patients report include dizziness, lethargy, sleepiness, hyperactivity, loose stools, jitteriness, and an increased heart rate. Less commonly reported side effects include irritability, increased seizure activity, decreased appetite, alertness, heart palpitations, and insomnia. Minor side effects like headache have also often been reported in conjunction with poor quality CBD oil tinctures.
If you want to start taking CBD but you’re also taking other prescription medications, you should be aware that there is a chance for drug interaction.
There is a family of liver enzymes, called the cytochrome P450 group, that works to metabolize roughly 60% of the pharmaceutical drugs we consume. At high enough doses, CBD inhibits the activity of these enzymes, which will increase the duration of action and effect of prescription drugs metabolized by the P450 group. Unfortunately, because of the individuality of each person’s endocannabinoid system and because each drug seems to have its own unique threshold for CBD sensitivity, there is no standard cut-off dose to avoid this interaction, meaning you will need to work with a doctor to monitor the blood levels of your medications while taking CBD.
If you want to try CBD with other prescription medications, be sure to talk to your doctor or pharmacist. A simple way of determining if you should be concerned about possible CBD interactions is to ask your doctor or pharmacist whether you should avoid eating grapefruit while taking the medication in question. CBD interacts with medications in the same way grapefruit does, only it has much more potent effects. So if the answer is yes, you will know interaction could be an issue for you.
Here are types of drugs that use the cytochrome P450 enzyme system and can interact with CBD:
- HMG-CoA reductase inhibitors
- Calcium channel blockers
- HIV antivirals
- Immune modulators
- Beta blockers
- Proton pump inhibitors (PPIs)
- Nonsteroidal anti-inflammatory drugs (NSAIDs)
- Angiotensin II blockers
- Oral hypoglycemic agents
If your doctor can’t advise you on taking CBD along with your prescription medications, seek out the advice of a licensed cannabis doctor or nurse.
- M. M. Bergamaschi et al., “Safety and Side Effects of Cannabidiol, a Cannabis Sativa Constituent,” Current Drug Safety 6, no. 4 (2011): 237–49, doi:10.2174/157488611798280924.
- Amanda Reiman, Mark Welty, and Perry Solomon, “Cannabis as a Substitute for Opioid-Based Pain Medication: Patient Self-Report,” Cannabis and Cannabinoid Research 2, no. 1 (2017): 160–66, doi:10.1089/can.2017.0012.
- Kevin F. Boehnke, Evangelos Litinas, and Daniel J. Clauw, “Medical Cannabis Use Is Associated with Decreased Opiate Medication Use in a Retrospective Cross-Sectional Survey of Patients with Chronic Pain,” The Journal of Pain 17, no. 6 (2016): 739–44, doi:10.1016/j.jpain.2016.03.002.
- Gustavo Gonzalez-Cuevas et al., “Unique Treatment Potential of Cannabidiol for the Prevention of Relapse to Drug Use: Preclinical Proof of Principle,” Neuropsychopharmacology (2018), doi:10.1038/s41386-018-0050-8.
- Kerstin Iffland and Franjo Grotenhermen, “An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies,” Cannabis and Cannabinoid Research 2, no. 1 (2017): 139–54, doi:10.1089/can.2016.0034.