Using medical cannabis and Lamictal may increase side effects such as dizziness, confusion, drowsiness, and difficulty concentrating. Elderly consumers may also experience impairment in judgment. That being said, none of these side effects were proven to result from CBD use per se. When it comes to interactions between CBD and Lamictal, it can make the medication more or less effective, depending on the dosage.
Scientists call it the ‘first-pass effect’ or ‘first-pass metabolism.’
CBD Oil and Omeprazole
Studies from the Indiana University Department of Medicine have provided a list of pharmaceutical drugs and medications which shouldn’t be taken with CBD.
There’s also a group of drugs called “prodrugs” that first need to be processed into their therapeutic compounds instead of being therapeutic compounds on their own. In plain English, the inactive compound is consumed, and once in the body, it turns into the active compound.
How Drugs Interact: Understanding Drug Metabolism
The list of drugs that we’ve mentioned above is by no means definite and doesn’t include all the pharmaceutical substances that may interact with CBD. Similarly, not all the medication from these categories will necessarily cause an interaction — as is the case for antibiotics and Ibuprofen.
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.
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.
Does the form of CBD matter?
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.
As for other drugs, well, most haven’t been studied yet. There is preliminary evidence that CBD could have a similar effect to grapefruit juice, impairing how your body metabolizes drugs, and raising serum levels of those medications in your body. And, because cytochrome P450 is responsible for the metabolism of numerous medications , proceed with caution before mixing any prescription pharmaceutical with CBD, Dr. Alloway says.
Despite the not-so-great news about CBD for patients using tacrolimus, for some people, CBD is actually life-changing in a positive way. In 2018, for example, the CBD-derived medication Epidiolex received FDA approval for the treatment of Lennox-Gastaut syndrome and Dravet syndrome, two very rare and very severe forms of epilepsy.
Furthermore, most prescription medications used to manage these conditions are metabolized by cytochrome P450, making it entirely possible that CBD could interfere with—rather than enhance—treatment.
Does CBD interact with medications?
“There is no role right now for CBD in managing mental disorders that I [treat], such as depression, bipolar disorder … anxiety and ADHD,” he says. “We just don’t have the evidence that supports [it].”
But claims that CBD aids in the treatment of certain mental health and psychiatric conditions, don’t pass muster, says Roger McIntyre, MD , professor of psychiatry and pharmacology at the University of Toronto.
Is CBD marijuana?
“Herbal products are drugs,” says Rita Alloway, Pharm.D. , research professor of nephrology at the University of Cincinnati College of Medicine. “Just because [something] is herbal … doesn’t mean it can’t interact with any of the pharmaceutically manufactured drugs that you may be taking.”
While CBD is one of the active ingredients in marijuana, using CBD itself will not get you high (the component that does that is called tetrahydrocannabinol, or THC). CBD is really just a molecule within the hemp variety of the cannabis plant, and there is at least some anecdotal evidence and preliminary research suggesting that the extraction created from this molecule has some health benefits.