Most cannabis enthusiasts know CBD is relatively benign. But are there CBD oil side effects? Here’s our full explainer.
Photography by Georgia Love for Herb
A rapidly growing number of Americans are turning to CBD oil to help with things like pain, anxiety, and sleep—and many of them are ditching prescription drugs in the process. But does CBD oil have any side effects?
The short answer is yes. There has never been a recorded casualty from CBD, and most people could take a lot of CBD oil without any noticeable side effects. In fact, according to a 2011 study, 1,500 mg of CBD daily was “well-tolerated in humans,” which is more CBD oil than most people take in a month.
What’s more, the World Health Organization (WHO) recently found that CBD oil is not likely to be abused. In fact, it’s been found to help addicts stay away from more dangerous substances, like cocaine and opioids. Compared to many of the prescription drugs people are replacing with CBD oil—like Klonopin for anxiety, Ambien for sleep, Vicodin for pain, and even Adderall for ADHD—all of which are addictive – CBD oil is a much safer alternative.
Not to mention, CBD doesn’t produce the same intoxicating, euphoric effects as its cousin, THC. Therefore, one of CBD’s most desirable qualities for folks seeking medical relief is the fact that getting high is not one of the side effects.
Although CBD doesn’t produce a high like THC, it does affect the body’s endocannabinoid system as well as modulate the speed of certain neurotransmitters. That’s what makes it so beneficial for conditions like anxiety, insomnia, epilepsy, ADHD, and chronic pain.
A 2017 scientific review looked at CBD’s safety and side effects and found the most commonly reported CBD oil side effects were:
According to the recent book, Healing with CBD: How Cannabidiol Can Transform Your Health Without the High, authors Eileen Konieczny, RN and Lauren Wilson found, anecdotally, that the most common CBD oil side effects are “dizziness, lethargy, sleepiness, hyperactivity, loose stools, jitteriness, and an increased heart rate.”
In the book, Konieczny and Wilson also explore some less common CBD side effects, including: “irritability, increased seizure activity, decreased appetite, alertness, heart palpitations, and insomnia. Minor side effects like headaches have also been reported in conjunction with poor quality CBD oil tinctures.”
Many of CBD oil’s side effects are caused by either the dose or poor quality of the oil. Therefore, it’s important to be thorough when researching CBD products and make sure to use this handy checklist before making a purchase.
CBD’s effects depend on the dose because of cannabis’ biphasic effect—a drug’s ability to produce opposite effects depending on whether a low or high dose is taken. For high-THC cannabis, the biphasic effect becomes most apparent when thinking about the plant’s potential to create euphoric, relaxing experiences in low to moderate doses, but also paranoid, anxiety-ridden experiences in the same person at a high dose.
With CBD, the biphasic effect becomes clear when considering CBD oil’s ability to make a person either alert or sleepy, depending on the dose. At one to 10 mg of CBD, many people report feeling better able to concentrate, especially those with anxiety or attention issues. However, before bed, those same people will want to take a higher dose of CBD oil, so they’re not stimulated before bed. Plus, because of CBD’s biphasic effect, it becomes sedating at higher doses.
One important CBD oil side effect we can’t forget to mention is the cannabinoid’s potential to interact with prescription drugs. According to Konieczny and Wilson’s book, 60 percent of the pharmaceutical drugs people consume are metabolized in the liver by a certain family of enzymes called the cytochrome P450 group. The thing is, CBD inhibits the activity of those enzymes, which can alter the effectiveness of prescription meds.
Therefore, it’s important to talk to your doctor before adding CBD oil to your daily routine. A good rule of thumb is to check if your prescription has a warning about a drug interaction with grapefruit. If so, that prescription will likely also have an interaction with cannabis and CBD, and so your dose may need to be adjusted by a doctor to account for the CBD.
CBD oil is proven safe and many studies are showing it’s effective too, but every individual’s endocannabinoid system is different. Therefore, CBD oil side effects are possible, but they’ll be generally very mild, especially in comparison to their pharmaceutical drug counterparts. It’s important to “start low and go slow,” as Konieczny and Wilson recommend, and in time, you’ll learn the optimal CBD doses for your body and needs.