An increasing number of folks are using CBD to treat aches, pains, and other maladies… But what if you’re already taking other medications? Will CBD interact with them?

Here’s everything you need to know about how CBD is metabolized (or broken down) by your body, which drugs to be mindful of when taking CBD, which ones shouldn’t impact it, and more.

The Simple Answer

So… Does CBD interact with medications? In some cases, yes. In others, no.

CBD and many medications are broken down by the same family of liver enzymes (also known as CYP450). Because CBD inhibits some of the enzymes in this family and speeds up others, it means your body will break down a number of other drugs more slowly or quickly if you chose to use both. Therefore, CBD could increase side effects of the other drug… or make it less effective.

“There is still a lot of uncertainty about how CBD interacts with drug-metabolizing enzymes in the body,”  shares Dr. Nina M. Bemben, a specialist on the topic of drug interactions. “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.”

Best Course of Action

The above is why you should speak with your doctor and ask them to correctly adjust the dose of both drugs. Getting the appropriate amount will make both more effective, while cutting down on the risk of side effects.

Not only should you talk with your doctor about prescriptions, but mention any vitamins or supplements you take as well. You should also discuss your CBD use with your surgeon if you have an upcoming operation because an anesthesiologist might decide to adjust your dose of anesthesia or even switch the kind of anesthesia they administer.

Also be sure to carefully monitor your body throughout use. If you start noticing signs of drowsiness, nausea, diarrea, or any other symptom, check back with your doctor.

Which drugs do I need to be mindful of?

Some of the more common drugs you should be mindful of when also taking CBD include:

  • Antidepressants (like Fluoxetine and Prozac)
  • Medications causing drowsiness (like antipsychotics and benzodiazepines)
  • Macrolide antibiotics (like erythromycin or clarithromycin)
  • Heart medications (some calcium channel blockers, amiodarone)
  • Blood thinners (like warfarin)
  • Thyroid medication (levothyroxine)
  • Several seizure medications (including clobazam, lamotrigine, and valproate)

You can also choose to use an online databases to evaluate drug-drug interactions. Though there are free sources out there, they tend to be less reliable than paid services. One popular site, drugs.com, allows patients to check the possible interactions of cannabidiol or cannabis (both THC and CBD) with a number of other medications.

The Grapefruit Test

Here’s an odd little piece of advice: Avoid CBD if your medications come with a grapefruit warning on the label. Food and Drug AdministrationTrusted Source states that grapefruit with these medications can cause a higher concentration than desired to hit your bloodstream. For some reason, CBD inhibits the same CYP3A4 enzymes that grapefruit does. Don’t ask us why.

CBD and Arthritis Medication

If you’re treating arthritis with CBD and another drug (like methotrexate or most other nonsteroidal anti-inflammatory drugs  called NSAIDs), experts say you shouldn’t expect to see any significant drug-drug interactions. Be careful with one NSAID called diclofenac, however, because there isn’t any information on how CBD affects it.

One caveat: rheumatologists often look for liver problems resulting from arthritis medications of all kinds (CBD and NSAIDs included).

When To Avoid CBD

Which leads us to our next point… those who suffer liver damage should probably avoid CBD. The reason? Animal research has found that CBD might cause an increase in liver enzymes for those taking methotrexate. Epileptic patients taking Epidiolex are more likely to develop abnormal liver enzymes.

Seniors and CBD Drug Interaction

Also keep in mind that drug-drug interactions impact seniors differently. Because the livers and kidneys of the elderly take longer to eliminate drugs from their bodies, there should be more precautions taken.

This age group is also more likely to be using several medications simultaneously. Whenever more factors are in play, the risk of side effects increases–that applies to any and all drugs being used.

If your medication contains a side effect of dizziness, seniors should be particularly careful. The combination of antidepressant fluoxetine and CBD could significantly increase fall risks.

Do CBD Creams Impact Other Medications?

Probably. The impact will most likely be reduced because topical products are absorbed more minimally into the system. However, research has not been satisfactorily developed in this area.

Written by:

Johanna H25 Feb 2021@zpolitis@csumb.edu
@exclusivezoepolitis@gmail.com