“Generally speaking, you can safely use CBD supplements when you’re taking antidepressants. However, there are a couple of concerns,” Dr. Peter Grinspoon, M.D., an instructor in medicine at Harvard Medical School, and the author of the memoir Free Refills: A Doctor Confronts His Addiction, tells Bustle. “The first concern is that CBD isn’t regulated by the FDA. You have to be careful that the CBD you’re getting is from a reliable supplier. For example, Consumer Reports recently put out an article on how to go shopping for CBD because they’ve done tests, and found some [supplement] formulations had no CBD. Some were inaccurately labeled, and other formulations even had some THC in them.” (THC is the cannabis compound that, unlike CBD, can get you high.)
According to statistics from the National Alliance on Mental Illness (NAMI), one in five U.S. adults live with a mental illness in any given year. Furthermore, as NBC News reported, a 2016 study revealed one in six people in the U.S. take some type of psychiatric medication, with antidepressants being the most widely prescribed. Limited research has shown that CBD may help alleviate symptoms of anxiety and sleep issues, as well as lower levels of inflammation in the body, though this research (and the dosages needed for these effects) is nowhere near conclusive. And that means you need to be careful if you’re choosing to consume it.
What’s more, Grinspoon says that CBD also inhibits “the system that metabolizes a lot of serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, and antipsychotics as well.” Meaning, taking CBD supplements while on these psychiatric medications could hypothetically interfere with how these medications are metabolized.
Dr. Patel worries in particular about any side effects or interactions that result in dizziness and may increase the risk of falls in the elderly. For example, using the antidepressant fluoxetine together with cannabis products can increase dizziness and drowsiness.
Tell your rheumatologist and anyone else who prescribes medication for you. If you need surgery, an anesthesiologist may choose a different dose or type of anesthesia if you’re using CBD.
People who take Epidiolex for epilepsy are more likely to develop abnormal liver enzymes, as well as sleepiness and other symptoms, if they are also using valproic acid to control seizures.
Are there some people who should stay away from CBD?
One common concern among people with chronic illness who use CBD is whether CBD can interfere with prescription drugs you may take for arthritis or other conditions.
CBD (cannabidiol) is seemingly everywhere, with oils, tinctures, pills, chocolates, gummy bears, and creams available all over the internet, at national drugstore chains, and perhaps at your local farmer’s market — even if you don’t live in a state where medical or recreational marijuana is legal.
Which health professionals need to know I’m trying CBD?
Yes, for several reasons. “As we age, our livers and kidneys may be slower to eliminate drugs from the body. In addition, older patients and those with chronic health problems are more likely to be using multiple medications, so the risk for drug interactions increases,” says Dr. Bemben.
“There is still a lot of uncertainty about how CBD interacts with drug-metabolizing enzymes in the body. We know that there are some drug-metabolizing enzymes that are affected by CBD, some that are not, and many others where we just don’t have any information yet,” says Dr. Bemben.
Many drugs are broken down by enzymes in the liver, and CBD may compete for or interfere with these enzymes, leading to too much or not enough of the drug in the body, called altered concentration. The altered concentration, in turn, may lead to the medication not working, or an increased risk of side effects. Such drug interactions are usually hard to predict but can cause unpleasant and sometimes serious problems.
While generally considered safe, CBD may cause drowsiness, lightheadedness, nausea, diarrhea, dry mouth, and, in rare instances, damage to the liver. Taking CBD with other medications that have similar side effects may increase the risk of unwanted symptoms or toxicity. In other words, taking CBD at the same time with OTC or prescription medications and substances that cause sleepiness, such as opioids, benzodiazepines (such as Xanax or Ativan), antipsychotics, antidepressants, antihistamines (such as Benadryl), or alcohol may lead to increased sleepiness, fatigue, and possibly accidental falls and accidents when driving. Increased sedation and tiredness may also happen when using certain herbal supplements, such as kava, melatonin, and St. John’s wort. Taking CBD with stimulants (such as Adderall) may lead to decreased appetite, while taking it with the diabetes drug metformin or certain heartburn drugs (such as Prilosec) may increase the risk of diarrhea.
CBD can alter the effects of other drugs
Products containing cannabidiol (CBD) seem to be all the rage these days, promising relief from a wide range of maladies, from insomnia and hot flashes to chronic pain and seizures. Some of these claims have merit to them, while some of them are just hype. But it won’t hurt to try, right? Well, not so fast. CBD is a biologically active compound, and as such, it may also have unintended consequences. These include known side effects of CBD, but also unintended interactions with supplements, herbal products, and over-the-counter (OTC) and prescription medications.
The researchers further warned that while the list may be used as a starting point to identify potential drug interactions with marijuana or CBD oil, plant-derived cannabinoid products may deliver highly variable cannabinoid concentrations (unlike the FDA-regulated prescription cannabinoid medications previously mentioned), and may contain many other compounds that can increase the risk of unintended drug interactions.
Doubling up on side effects
CBD has the potential to interact with many other products, including over-the-counter medications, herbal products, and prescription medications. Some medications should never be taken with CBD; the use of other medications may need to be modified or reduced to prevent serious issues. The consequences of drug interactions also depend on many other factors, including the dose of CBD, the dose of another medication, and a person’s underlying health condition. Older adults are more susceptible to drug interactions because they often take multiple medications, and because of age-related physiological changes that affect how our bodies process medications.