Due to its anti-inflammatory properties, many people use CBD for pain. Moreover, due to their pain, rheumatology and pain patients often suffer from and take medications for psychiatric comorbidities, such as depression.

Patients often supplement their prescribed medications with CBD products. As such, patients are increasingly interested in and concerned about the safety of CBD oil and CBD drug interactions.

Harold Wilson-Morkeh and colleagues performed a thorough research in a number of medical databases that contain information about drugs and drug interactions. They identified:

• 15 pain and psych medications with potential CBD drug interactions and

• 13 pain and psych medications with no suspected CBD interactions

Note: No reports of actual cases of adverse events exist that are due to the concomitant use of CBD and the following medications. However, due to the potential CBD drug interactions, doctors should monitor patients who take both CBD and these medications. Additionally, patients should also be on alert for potential adverse side effects.

In summary, CBD inhibits the breakdown (metabolism) of the following 15 medications, so there is a risk of overdose-like symptoms of the medications when taken together with CBD.

1. Amitriptyline

Amitriptyline is used to treat mental illnesses, such as depression and anxiety. However, CBD inhibits the enzymes that metabolize amitriptyline (cytochrome P450 isozymes CYP2D6, CYP2C19, CYP3A4, CYP1A2 and CYP2C9). As such, taking CBD along with amitriptyline may lead not only to added therapeutic effects, but also to adverse effects as well, such as:

drowsiness,anticholinergic syndrome, andheart problems (QT prolongation).

2. Celecoxib

Celecoxib is a COX-2 selective nonsteroidal anti-inflammatory drug (NSAID). CBD inhibits the liver enzymes that metabolize celecoxib (CYP2C9 and CYP3A4). So far, however, no reports of adverse effects in humans linked to concomitant use of CBD exist, but it nevertheless is a possibility.

3. Citalopram

Citalopram is a selective serotonin reuptake inhibitor (SSRI) antidepressant medication. CBD inhibits the liver enzymes that metabolize citalopream (CYP2C9 and CYP3A4). Because CBD inhibits two enzymes together, it might decrease levels of the citalopram in the blood and increase the risk of adverse events.

4. Etoricoxib

The CBD – drug interaction risk with etoricoxib is similar to that with celecoxib.

5. Fluoxetine

Fluoxetine is an SSRI antidepressant. Cannabidiol inhibits the enzymes that metabolize fluoxetine (CYP2D6 and CYP2C9). Again, no adverse effects reported so far exist that have resulted from taking CBD with fluoxetine, but this possibility is something that we need to keep in mind.

6. Gabapentin

The CBD – drug interaction risk with gabapentin is similar to that with amitriptyline.

7. Hydrocortisone

Hydrocortisone (cortisol) and prednisolone are steroid medications to treat inflammatory conditions. CBD inhibits the enzyme that metabolizes hydrocortisone and prednisolone (cytochrome CYP3A). Concomitant CBD use might decrease cortisol breakdown and increase the risk of corticosteroid side effects. As such, doctors should monitor patients who take both cannabidiol and steroid medications, and they should decrease their steroid medication doses if the is any sign of adverse effects.

8. Mirtazapine

Mirtazapine is an antidepressant. CBD inhibits the liver enzymes that metabolize mirtazapine (CYP1A2, CYP2D6 and CYP3A4). No adverse event reports exist yet, but given the possibility, doctors should monitor patients who take both CBD and mirtazapine.

9. Naproxen

Naproxen is an NSAID used to treat pain. CBD inhibits the enzyme that metabolizes naproxen (cytochrome CYP2C9). Although no information exists, but this might increase the risk of side effects due to taking both naproxen and CBD.

10. Paroxetine

Paroxetine is an SSRI antidepressant. CBD inhibits the enzyme that metabolizes paroxetine (cytochrome CYP2D6). Again, no reports about increased risk exist due to taking both CBD and paroxetine, but doctors should nevertheless monitor such patients.

11. Prednisolone

The CBD – drug interaction risk with prednisolone is similar to that with hydrocortisone.

12. Pregabalin

The CBD – drug interaction risk with pregabalin is similar to that with amitriptyline.

13. Sertraline

Sertraline is in SSRI antidepressant. CBD inhibits the enzyme that metabolizes sertraline (CYP3A4). Again, no reports about adverse events exist yet, but patients who take both CBD and sertraline should be cautious.

14. Tofacitinib

Tofacitinib is a medication used to treat arthritis and colitis. CBD inhibits the enzymes that metabolize tofacitinib (CYP3A4 and CYP2C19). Wilson-Morkeh and colleagues suggest that the treating physician reduces the dose of tofacitinib to 5 mg once a day if the patient also takes CBD.

15. Tramadol

Tramadol is an opioid pain medication. CBD inhibits the enzyme that metabolizes tramadol (CYP2D6). As such, adverse side effect might happen.

13 medications with no expected CBD drug interactions

Wilson-Morkeh and colleagues do not expect to have any potential CBD – drug interactions with the following medications:

1. Abatacept,

2. Adalimumab,

3. Anakinra,

4. Baricitinib,

5. Etanercept,

6. Infliximab,

7. Hydroxychloroquine,

8. Mesalazine,

9. Methotrexate,

10. Mycophenolate,

11. Rituximab,

12. Sulfasalazine

Reference: Wilson-Morkeh H, Al-Abdulla A, Sien L, Mohamed H, Youngstein T. Important drug interactions exist between cannabidiol oil and commonly prescribed drugs in rheumatology practice. Rheumatology (Oxford). 2020 Jan 1;59(1):249-251.

Original Article: https://treatmentwithcbd.com/15-medications-cbd-drug-interactions/