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cbd and plavix

Cbd and plavix

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.

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.

CBD can alter the effects of other drugs

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.

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.

Does the form of CBD matter?

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.

Conversely, for patients already taking a strong CYP3A4 or 2C9 inhibitor, the addition of THC should also be approached with caution. In these patients, starting with a smaller, sub-psychoactive dose should prevent accidental intoxications from occurring. The literature often suggests a starting dose of approximately 2.5 mg of THC, often considered to be the "psychoactive threshold".[1] However, I start all my patients with a smaller dose of THC, in the 1 mg range, thus avoiding not only the possible drug interactions, but also the possible genetic CYP3A4 and 2C9 polymorphisms which can also increase THC levels in certain individuals.

2. Collin, C., et al. “A Double-Blind, Randomized, Placebo-Controlled, Parallel-Group Study of Sativex, in Subjects with Symptoms of Spasticity Due to Multiple Sclerosis.” Neurological Research, vol. 32, no. 5, June 2010, pp. 451–59, doi:10.1179/016164109X12590518685660.

As for the topic of interactions with smoked cannabis (CYP 1A2), this too should not be a concern if we properly counsel our patients to avoid this route of administration. Vapourizers are just as effective and do not produce the compounds responsible for these interactions.

This is a very thorough article and is a good reminder of several significant drug interactions such as those seen with dabigatran, warfarin and clopidogrel.

However, though the data is biochemically accurate, it leaves the reader with an alarmist impression of many possible drug interactions with cannabinoids found in the cannabis plant. It is important to remember that most of these events occur very rarely in clinical practice, and I suggest taking a more pragmatic approach to address this problem. The following explanation should reassure the readers, and hopefully the authors!