The most comment side effects of CBD include drowsiness, gastrointestinal issues, dry mouth, reduced appetite, nausea, and interaction with other medications. Those are outlined in detail below.
In some cases, those who ingest CBD supplements might experience nausea, says Dr. Matharu-Daley. This depends on how sensitive the person is to CBD, as well as the amount they ingest.
Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital.
Also known as “cotton mouth,” CBD can potentially cause your mouth and eyes to feel very dry, notes Dr. Brent A. Bauer via Mayo Clinic. Though this side effect is more likely to occur with THC, it can happen with CBD, as well.
“Since discovering the endocannabinoid system (ECS) in the body in the 1990s, CBD has been researched more extensively. The ECS is a central regulatory system restoring normal balance and homeostasis in a range of human physiologic systems throughout the body and brain and has cannabinoid receptors and chemicals in its function,” explains Dr. Matharu-Daley.
For this study, nine healthy men took either 600 mg of CBD or the same dose of a placebo. According to the researcher, those treated with CBD had lower blood pressure before and after exposure to stressful stimuli (including exercise or extreme cold).
CBD oil is an extract of Cannabis indica or Cannabis sativa—the same plants that, when dried, make marijuana. CBD oil is believed by some to treat pain, reduce anxiety, and stimulate appetite in the same way that marijuana does, but without its psychoactive effects. CBD has also shown promise in treating certain types of seizures.
Part of this response could be explained by the way that CBD acts in the brain. In low doses, CBD may act as an agonist to several receptor sites, meaning it acts similarly to surrounding molecules that normally bind to the receptor, enhancing the signalling of those receptor sites. At higher doses, however, too much activity at the receptor site can lead to an opposite effect, negating the beneficial effects of CBD.
CBD oil should be avoided during pregnancy and breastfeeding. A 2018 study from the American Academy of Pediatrics warned women to avoid marijuana during pregnancy due to the potential risks to a baby’s development. Although it is unclear how CBD contributes, CBD is known to pass through the placental barrier.
To use CBD oil, place one or more drops under the tongue and hold the dose there for 30 to 60 seconds without swallowing. Capsules and gummies are easier to dose, although they tend to be more costly. CBD sublingual sprays are available as well.
Among the few human trials evaluating CBD’s anxiolytic effects was one published in the Brazilian Journal of Psychiatry in 2019. For this study, 57 men were given either CBD oil or a placebo before a public-speaking event. Anxiety was evaluated using physiological measures (such as blood pressure, heart rate, etc.) and a relatively reliable test for mood states known as the Visual Analog Mood Scale (VAMS).
Potential drug-drug interactions with CBD include:
If you’re suspicious about the safety of your current CBD products, do yourself a favor and throw them away. CBD oil is a concentrated plant-based extract that goes into your body — expect its quality to be at least as high as the foods you eat.
So we thought we’d compile all the negative scientific evidence into one handy guide, to help you decide whether CBD is right for you. We’ll cover the different side effects you might encounter and what they could mean, as well as what current research says about trying CBD if you are:
You’re immune compromised. (Most evidence disproves this concern) CBD is known as an immunomodulator because it can calm down a hyperactive immune system , but some worry this could harm people whose immune systems are already impaired, like HIV sufferers. Although we don’t have evidence specifically testing CBD against this fear, many studies have been done using the whole cannabis plant. Research shows that cannabis helps relieve pain and other HIV-related symptoms without causing severe side effects . And when marijuana is tested against specific HIV symptoms like liver fibrosis, cannabinoids do not appear to worsen it . Although current evidence suggests that CBD could be more helpful than harmful for immune-compromised individuals, the jury is still out.
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If you check the US government’s clinical trials database , you’ll see that more than 50 trials are either currently active or recruiting participants for conditions ranging from arthritis to drug abuse disorders. (Foria is participating in this movement with a 400-person study on the efficacy of our CBD suppositories for menstrual cramps and pain — although this isn’t a clinical trial, but a less-expensive self-reported survey.)
You’re trying to conceive. (Not enough evidence) Natural cannabinoids are produced and used throughout our bodies as messengers. One of their most important uses is to help our bodies coordinate conception and pregnancy . At the moment, it’s a complete mystery what extra cannabinoids do to our bodies’ reproductive capabilities. Some evidence suggests that regular cannabis users have slightly lower fertility rates , although more comprehensive assessments of the data generally agree that this effect is minimal at most — and is more likely caused by THC than CBD. However, if you are having difficulty conceiving, discuss your use of CBD or cannabis products with your doctor.
Side effects based on high-dose clinical trials
Sometimes CBD products don’t contain any CBD at all — in which case you won’t experience any effects, positive or negative.