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CBD might not mix with your meds

The Portland Clinic pharmacy team offers important cautions

CBD oil

If you’ve been thinking about trying cannabidiol — more commonly known as CBD — welcome to the rapidly growing club. Interest in CBD as a treatment for pain, insomnia, anxiety and other complaints has been rising steadily ever since Oregon and other states legalized cannabis (marijuana).

CBD is one of many natural chemical compounds found in cannabis, but unlike the plant’s other well-known chemical, THC, it has no psychoactive or mind-altering effects. Instead, CBD owes its popularity to its therapeutic effects. Before you try it, however, be aware that it carries potential risks, as well — especially if you take other medications or have liver problems.

CBD benefits

To date, the only FDA-approved use of CBD is a prescription medication called Epidiolex, which treats seizure disorders. Other over-the-counter uses, while widely promoted, need further study to support their claims. These include the following:

Insomnia

With its naturally sedating effects, CBD is used by many people as a sleep aid.

Anxiety and depression

CBD has shown promising results for many people with these issues.

Pain and inflammation

Some patients with arthritis and cancer find CBD helpful in reducing these symptoms.  

CBD risks

Much remains unknown about how CBD works, its therapeutic benefits and its safety. For your own safety, it’s important to be aware of the known risks. They include the following:

CBD liver harm

CBD can be harmful to the liver. People with liver impairment should be cautious or avoid it.

CBD medication interactions

Because of its effect on the liver and liver enzymes, CBD can interfere with many medications, either increasing their levels in the blood to potentially toxic levels, or decreasing levels and reducing their effectiveness. Certain seizure medications, antidepressants, muscle relaxers, and drugs that can suppress the central nervous system (such as benzodiazepines, sleeping pills and opioids), among many other medications, may have strong interactions.

It’s important to talk to your doctor or pharmacist before using CBD to make sure you’re not taking a medication that will interact badly with it.

CBD drowsiness and other side effects

Because CBD causes drowsiness on its own, it also increases the drowsiness caused by other medications, including antihistamines (such as Benadryl), benzodiazepines (Xanax, Ativan, Valium), antipsychotics, antidepressants and opioids, as well as alcohol and supplements such as kava, melatonin and St. John’s Wort.

CBD’s sedating effects are similar to alcohol, so it’s not a good idea to use it if you need to drive or to do anything that requires mental alertness. Other common side effects of CBD include diarrhea and changes in appetite and mood.

CBD safety and regulation

Over-the-counter CBD products are not regulated by the FDA. Although most are extensively tested, there is still a possibility of error (such as the mix-up reported last September in The Oregonian), so be wary that products might not be 100% CBD as labeled.

Considering CBD? Talk to your doctor or pharmacist first

If you have questions about how your medications will interact with CBD, reach out to your doctor or local pharmacist for help. Pharmacists are great resources and can help come up with alternative therapies if CBD is not a good option for you.