The Potential Side Effects of CBD
Wendy Rose Gould is a lifestyle reporter with over a decade of experience covering health and wellness topics.
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Generally speaking, CBD is considered a safe substance when applied topically or taken orally. There are, however, some potential side effects to keep in mind when using this substance, the majority of which are mild.
Common Side Effects of CBD
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.
Some common side effects when using CBD include drowsiness and sedation. This is also considered a benefit, but Dr. Jas Matharu-Daley, a physician and chief medical officer for a CBD brand, notes that the effects might be too strong if you’re also taking CBD with other sedating medications.
Some people may get diarrhea or liver problems [when using CBD]. This is dependent on the individual and their medical history, so monitoring is important,” says Dr. Matharu-Daley.
Also known as “cotton mouth,” CBD can potentially cause your mouth and eyes to feel very dry. Though this side effect is more likely to occur with THC, it can happen with CBD as well.
Can Interact With Other Medications
CBD might interfere with the other medications you take. Dr. Matharu-Daley says it’s important to talk to your doctor about whether CBD could affect your existing prescriptions.
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.
Because CBD supplements come in so many different forms—such as oils, gummies, tinctures, and vapors—the amount that’s actually absorbed can vary drastically. This, combined with each person, will ultimately affect which (if any) CBD side effects you might experience.
What Is Cannabidiol (CBD)?
CBD—the abbreviation for cannabidiol, a substance that’s generally derived from the hemp plant—has skyrocketed in popularity over the last five years. In fact, according to research, “CBD” as a Google search term remained stable from 2004 to 2014 but has since ballooned by up to 605%.
CBD is one of the many chemical compounds that is found in the cannabis plant—referred to as cannabis sativa. There are two primary parts of the plant that humans use. One is THC, or Delta-9-Tetrahydrocannabinol, and the other is CBD. Though they’re from the same plant, THC and CBD are quite different from each other.
“CBD is not an intoxicating substance, whereas THC is a psychoactive that can get you high,” explains Dr. Jas Matharu-Daley, a physician and consultant for a brand that specializes in CBD production.
Are There Any Benefits Associated With Using CBD?
There are several reasons why someone might want to use CBD. The substance can be found in a multitude of products ranging from pain-relieving creams to edible tinctures to skincare. Research is still underway, but over the last few decades scientists have become more aware of how CBD might be beneficial when applied either topically or ingested.
“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.
CBD benefits include the following:
- CBD can have positive impact on the brain. In fact, Dr. Matharu-Daley says that the substance is legally prescribed in a specific medication for certain severe forms of epilepsy in children.
- It has also been shown to have anti-inflammatory properties, which is why you often see CBD in topical products such as oils, creams, and lotions.
- Some research points to CBD’s ability to relieve stress and anxiety.
- It has been used as a nausea treatment in some countries.
- CBD may potentially reduce pain symptoms.
- It has antioxidant properties, which means it can help fight off free radical damages that leads to premature aging.
- Regarding skincare, CBD may help reduce excessive oil production in those with very oily skin types.
Ultimately, the primary reasons why people use CBD is because it tends to have calming, relaxing, pain-reducing effects. It has been used to alleviate joint pain and nerve pain, reduce anxiety and stress, treat insomnia, improve migraines, and address nausea.
CBD Is Still an Unregulated Substance
It’s important to point out that CBD is not regulated by the FDA and therefore dosages might not be accurate. It’s also difficult to know what an appropriate dose is the first time you try a new product.
“If the CBD is from a reputable source and one that has been inspected by a third-party independent lab, the content of CBD is more reliable,” notes Dr. Matharu-Daley. “The CBD should be organically grown, free of pesticides and heavy metals, and not sourced in food which can affect absorption. Generally, CBD is safe and side effects are few at low doses.”
A Word From Verywell
CBD is technically an unregulated substance in the United States and therefore it ought to be used with caution. This is especially important for those taking additional medications and/or those with ongoing medical issues. That said, preliminary research on CBD and its benefits are promising in relation to helping with mild to moderate health concerns and it is generally considered a safe substance. Health professionals do not consider CBD a cure-all for serious medical issues, including cancer.
As with any sort of supplement, we recommend speaking to your medical doctor about whether using CBD makes sense for you. Your doctor can also recommend certain products that align with your needs and help ensure you get the correct dosage.
What Are the Benefits of CBD?
More than 60 percent of CBD users were taking it for anxiety, according to a survey of 5,000 people. Does it help?
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By Dawn MacKeen
The CBD industry is flourishing, conservatively projected to hit $16 billion in the United States by 2025. Already, the plant extract is being added to cheeseburgers, toothpicks and breath sprays. More than 60 percent of CBD users have taken it for anxiety, according to a survey of 5,000 people, conducted by the Brightfield Group, a cannabis market research firm. Chronic pain, insomnia and depression follow behind. Kim Kardashian West, for example, turned to the product when “freaking out” over the birth of her fourth baby. The professional golfer Bubba Watson drifts off to sleep with it. And Martha Stewart’s French bulldog partakes, too.
What is CBD?
Cannabidiol, or CBD, is the lesser-known child of the cannabis sativa plant; its more famous sibling, tetrahydrocannabinol, or THC, is the active ingredient in pot that catapults users’ “high.” With roots in Central Asia, the plant is believed to have been first used medicinally — or for rituals — around 750 B.C., though there are other estimates too.
Cannabidiol and THC are just two of the plant’s more than 100 cannabinoids. THC is psychoactive, and CBD may or may not be, which is a matter of debate. THC can increase anxiety; it is not clear what effect CBD is having, if any, in reducing it. THC can lead to addiction and cravings; CBD is being studied to help those in recovery.
Cannabis containing 0.3 percent or less of THC is hemp. Although last year’s Farm Bill legalized hemp under federal law, it also preserved the Food and Drug Administration’s oversight of products derived from cannabis.
What are the claims?
CBD is advertised as providing relief for anxiety, depression and post-traumatic stress disorder. It is also marketed to promote sleep. Part of CBD’s popularity is that it purports to be “nonpsychoactive,” and that consumers can reap health benefits from the plant without the high (or the midnight pizza munchies).
Just as hemp seedlings are sprouting up across the United States, so is the marketing. From oils and nasal sprays to lollipops and suppositories, it seems no place is too sacred for CBD. “It’s the monster that has taken over the room,” Dr. Brad Ingram, an associate professor of pediatrics at the University of Mississippi Medical Center, said about all the wild uses for CBD now. He is leading a clinical trial into administering CBD to children and teenagers with drug-resistant epilepsy.
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- Removing the Stigma: Misconceptions about how PTSD develops and its symptoms, can prevent people from seeking treatment.
- Psychedelic Drugs: As studies explore the therapeutic value of substances like MDMA, veterans are becoming unlikely advocates for their decriminalization.
- Virtual Reality: A treatment using new technology to immerse patients in a simulation of a memory could helpthemovercome trauma.
- Pandemic Trauma: Covid-19 has exacerbated mental health issues among medical workers, putting them at great risk of developing PTSD.
Does CBD work?
“It’s promising in a lot of different therapeutic avenues because it’s relatively safe,” said James MacKillop, co-director of McMaster University’s Michael G. DeGroote Center for Medicinal Cannabis Research in Hamilton, Ontario.
Last year, the F.D.A. approved Epidiolex, a purified CBD extract, to treat rare seizure disorders in patients 2 years or older after three randomized, double-blind and placebo-controlled clinical trials with 516 patients that showed the drug, taken along with other medications, helped to reduce seizures. These types of studies are the gold standard in medicine, in which participants are divided by chance, and neither the subject nor the investigator knows which group is taking the placebo or the medication.
While there is hope for treating other conditions with the plant extract, Epidiolex remains the only CBD-derived drug approved by the F.D.A. Most of the research on cannabidiol has been in animals, and its current popularity has outpaced science. “We don’t have the 101 course on CBD quite figured out yet,” said Ryan Vandrey, an associate professor of psychiatry and behavioral sciences at Johns Hopkins University School of Medicine.
Does CBD help anxiety and PTSD?
For students with generalized social anxiety, a four-minute talk, with minimal time to prepare, can be debilitating. Yet a small experiment in the journal Neuropsychopharmacology found that CBD seemed to reduce nervousness and cognitive impairment in patients with social anxiety in a simulated public speaking task.
However, a double-blind study found healthy volunteers administered CBD had little to no change in their emotional reaction to unpleasant images or words, compared to the placebo group. “If it’s a calming drug, it should change their responses to the stimuli,” said Harriet de Wit, co-author of the study and a professor in the University of Chicago’s department of psychiatry and behavioral neuroscience. “But it didn’t.”
Many soldiers return home haunted by war and PTSD and often avoid certain activities, places or people associated with their traumatic events. The Department of Veterans Affairs is funding its first study on CBD, pairing it with psychotherapy.
“Our top therapies attempt to break the association between reminders of the trauma and the fear response,” said Mallory Loflin, an assistant adjunct professor at the University of California, San Diego and the study’s principal investigator. “We think that CBD, at least in animal models, can help that process happen a lot faster.” While large clinical trials are underway, psychologists say there isn’t compelling evidence yet as to whether this is a viable treatment.
Does CBD help sleep and depression?
Up in the wee hours of the night, stuck watching videos of puppies? CBD may be promising as a sleep aid; one of the side effects of the Epidiolex trials for epilepsy was drowsiness, according to Mr. MacKillop, a co-author of a review on cannabinoids and sleep. “If you are looking for new treatments for sleep, that may be a clue,” he said.
But he cautions that the side effects could have been because of an interaction with other medications the children were taking to control the seizures. So far, there hasn’t been a randomized, placebo-controlled, double-blind trial (the gold standard) on sleep disorders and CBD.
A recent chart review of 72 psychiatric patients treated with CBD found that anxiety improved, but not sleep. “Over all, we did not find that it panned out as a useful treatment for sleep,” said Dr. Scott Shannon, assistant clinical professor of psychiatry at the University of Colorado, Denver and the lead author of the review in The Permanente Journal.
Sleep can be disrupted for many reasons, including depression. Rodents seemed to adapt better to stressful conditions and exhibited less depressive-like behavior after taking CBD, according to a review in Journal of Chemical Neuroanatomy. “Surprisingly, CBD seems to act faster than conventional antidepressants,” wrote one of the authors of a new review, Sâmia Joca, a fellow at the Aarhus Institute of Advanced Studies in Denmark and an associate professor at the University of São Paulo in Brazil, in an email interview. Of course, it’s difficult to detect depression in animals, but the studies that Ms. Joca and her colleagues reviewed suggested that in models of chronic stress exposure, the mice and rats treated with CBD were more resilient.
But without clinical trials in humans, psychologists say CBD’s effect on depression is still a hypothesis, and not an evidence-based treatment.
Is CBD harmful?
“If you take pure CBD, it’s pretty safe,” said Marcel Bonn-Miller, an adjunct assistant professor at the University of Pennsylvania’s Perelman School of Medicine. Side effects in the Epidiolex trial included diarrhea, sleepiness, fatigue, weakness, rash, decreased appetite and elevated liver enzymes. Also, the safe amount to consume in a day, or at all during pregnancy, is still not known.
Recently, the F.D.A. sent a warning letter to Curaleaf Inc. about its “unsubstantiated claims” that the plant extract treats a variety of conditions from pet anxiety and depression to cancer and opioid withdrawal. (In a statement, the company said that some of the products in question had been discontinued and that it was working with the F.D.A.)
Dr. Smita Das, chair of the American Psychiatric Association’s Council on Addiction Psychiatry’s cannabis work group, does not recommend CBD for anxiety, PTSD, sleep or depression. With patients turning to these to unproven products, she is worried that they may delay seeking appropriate mental health care: “I’m dually concerned with how exposure to CBD products can lead somebody into continuing to cannabis products.”
Some CBD products may contain unwanted surprises. Forensic toxicologists at Virginia Commonwealth University examined nine e-liquids advertised as being 100 percent natural CBD extracts. They found one with dextromethorphan, or DXM, used in over-the counter cough medications and considered addictive when abused; and four with a synthetic cannabinoid, sometimes called Spice, that can cause anxiety, psychosis, tachycardia and death, according to a study last year in Forensic Science International.
Earlier research found fewer than a third of 84 products studied contained the amount of CBD on their labels. Some users of CBD have also failed drug tests when the product contained more THC than indicated.
This year, 1,090 people have contacted poison control centers about CBD, according to the American Association of Poison Control Centers. Over a third are estimated to have received medical attention, and 46 were admitted into a critical care unit, possibly because of exposure to other products, or drug interactions. In addition, concern over 318 animals poured into the American Society for the Prevention of Cruelty to Animals’ Animal Poison Control Center.
Is CBD a scam or not?
A few drops of CBD oil in a mocha or smoothie are not likely to do anything, researchers contend. Doctors say another force may also be at play in people feeling good: the placebo effect. That’s when someone believes a drug is working and symptoms seem to improve.
“CBD is not a scam,” said Yasmin Hurd, director of the Addiction Institute of Mount Sinai in New York City who led a double-blind study of 42 recovering heroin addicts and found that CBD reduced both cravings and cue-based anxiety, both of which can cycle people back into using. “It has a potential medicinal value, but when we are putting it into mascara and putting it into tampons, for God’s sake, to me, that’s a scam.”