Drug & supplement interaction

Cannabidiol (cbd) + Treprostinil (Inh)

Treprostinil (Inh) brand name: Tyvaso.

Moderate Interaction
Medically reviewed by · Updated October 2026
The bottom line Moderate

Cannabidiol (cbd) has a moderate interaction with Treprostinil (Inh). Theoretically, cannabidiol might increase levels of drugs metabolized by CYP2C8.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Cannabidiol (cbd) and Treprostinil (Inh)

Here is the interaction we found between these two, with the evidence behind it.

Moderate

CYTOCHROME P450 2C8 (CYP2C8) SUBSTRATES

Why this applies to Treprostinil (Inh)

Treprostinil (Inh) falls under CYTOCHROME P450 2C8 (CYP2C8) SUBSTRATES — the group Cannabidiol (cbd) interacts with.

Theoretically, cannabidiol might increase levels of drugs metabolized by CYP2C8.
In vitro research shows that cannabidiol inhibits CYP2C8. However, this interaction has yet to be reported in humans. Until more is known, use with caution. Theoretically, concomitant use of cannabidiol with CYP2C8 substrates might increase the risk for adverse effects from these substrates.
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the simple version: your inhaled treprostinil (Tyvaso) is cleared from your body partly by a liver enzyme called CYP2C8. In lab (test tube) studies, CBD appears to slow that same enzyme down. If that happened in real life, treprostinil could hang around a bit longer than usual and its effects could stack up.

For treprostinil, that might mean stronger versions of its typical side effects, like flushing, headache, jaw pain, nausea, a faster heartbeat, or lightheadedness from lowered blood pressure. I want to be honest, though: this is only theoretical right now and has not actually been reported in people. So don't panic, but do give your pharmacist or doctor a heads-up before adding CBD, so they can watch how you feel.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Epidiolex (cannabidiol) prescribing information. Greenwich Biosciences, Inc., Carlsbad, CA, 2019. Available at: https://www.epidiolex.com/sites/default/files/EPIDIOLEX_Full_Prescribing_Information.pdf (accessed 5/9/2019)

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Cannabidiol (cbd) Also Interacts With Other Medications

Cannabidiol (cbd) has 1,051 moderate known drug interactions in our database — the Treprostinil (Inh) one above is one of them. If you take anything else, check it against the full list below.

Moderate 1,051 No known interaction 1,779 (incl. Treprostinil (Inh))
Taking anything else?

Check Another of Your Medications Against Cannabidiol (cbd)

Covers the 2,830 medications we’ve checked against Cannabidiol (cbd). Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Treprostinil (Inh)

This page covers Cannabidiol (cbd) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Treprostinil (Inh) page lists 275 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: American Hellebore (major), American Mistletoe (major), Danshen (major), Piracetam (major) and Tyramine (major).

By severity: 5 major · 251 moderate · 19 minor.

From our pharmacist’s overview on the Treprostinil (Inh) page

“Inhaled treprostinil (Tyvaso) relaxes blood vessels in the lungs to treat pulmonary hypertension, and it also blunts platelet clotting, which is why this list of 275 ingredients warrants real vigilance rather than a shrug. Two themes cover almost everything.”

Reviewed by 2 · Jul 18, 2026

Open the Treprostinil (Inh) interaction page

How much people look this up

Where Cannabidiol (cbd) and Treprostinil (Inh) Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Cannabidiol (cbd)
Top half

#457 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Treprostinil (Inh)
Top half

#724 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Cannabidiol (cbd)

What is Cannabidiol (cbd)?

  • Anxiety and stress
  • Sleep problems
  • Chronic pain
  • Certain seizure disorders
  • Inflammation

CBD is a compound from the cannabis (hemp) plant that does not cause a 'high.' It has strong evidence only for certain rare seizure disorders (as a prescription drug), while most other popular uses are still backed by limited or early research. Product quality varies a lot, so talk with your pharmacist or doctor before using it, especially if you take other medicines.

Read the full Cannabidiol (cbd) monograph & all interactions
Medication

About Treprostinil Oral Inhalation

What Is Treprostinil Oral Inhalation Used For?

Brand name: Tyvaso

Treprostinil oral inhalation is used to treat two serious lung conditions that raise pressure in the blood vessels of the lungs. It helps improve how much physical activity you can do.

Tyvaso inhalation solution and Tyvaso DPI are both indicated to treat pulmonary arterial hypertension (PAH; WHO Group 1) and pulmonary hypertension associated with interstitial lung disease (PH-ILD; WHO Group 3). Clinical studies establishing effectiveness in PAH primarily included patients with moderate symptoms (NYHA Class III) whose PAH was idiopathic, heritable, or related to connective tissue disease. Studies in PH-ILD primarily included patients with idiopathic interstitial pneumonia, combined pulmonary fibrosis and emphysema, or connective tissue disease-related lung disease.

See full Treprostinil Oral Inhalation drug information
Keep checking

Other Drugs & Cannabidiol (cbd)

Browse every other medication we’ve checked against Cannabidiol (cbd) — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
1,051Moderate
0Minor
1,778No known interaction
1,051 Moderate 1,778 No interaction
Moderate

1,051 interactions

Showing 60 of 1,051 moderate interactions — see all 1,051 on the Cannabidiol (cbd) page.

No interaction 1,778 drugs checked — show the list

We also checked Cannabidiol (cbd) against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 1,778 medications checked with no known interaction — see the full Cannabidiol (cbd) list.

See the full Cannabidiol (cbd) interactions page
See every supplement checked against Treprostinil (Inh), ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
Cannabidiol (cbd) monograph › Uses, safety, and every drug interaction in one place Treprostinil (Inh) supplement interactions › Every supplement checked against Treprostinil (Inh), ranked by severity Treprostinil Oral Inhalation drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Cannabidiol (cbd) and Treprostinil (Inh) Together: Common Questions

Can you take Cannabidiol (cbd) with Treprostinil (Inh)?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Cannabidiol (cbd) and Treprostinil (Inh) interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Treprostinil (Inh) and Cannabidiol (cbd)?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.