Drug & supplement interaction

Canadian Hemp + Dexmethylphenidate

Dexmethylphenidate brand name: Focalin.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Oct 4, 2026
The bottom line No known interaction

We found no known interaction between Canadian Hemp and Dexmethylphenidate in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Canadian Hemp and Dexmethylphenidate

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Dexmethylphenidate and Canadian Hemp in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Canadian Hemp safety at a glance

Canadian Hemp overall Avoid It contains toxic cardiac glycosides and is considered a poisonous plant, not a safe supplement.
Pregnancy Likely Unsafe When used orally due to the toxic potential of its cardiac glycoside constituents; avoid using. Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally due to the toxic potential of its cardiac glycoside constituents; avoid using. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Dexmethylphenidate and Canadian Hemp? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Dexmethylphenidate

Interactions in our licensed database are recorded against drug classes, not just single drug names. Dexmethylphenidate is filed under 5 classifications — including stimulant drugs, serotonergic drugs, serotonergic drugs. Canadian Hemp has documented interactions with 2 drug classes — the most serious being digoxin (lanoxin) (moderate) and diuretic drugs (moderate) — and none of Dexmethylphenidate’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Canadian Hemp Does Interact With Other Medications

Canadian Hemp has 76 moderate known drug interactions in our database — Dexmethylphenidate isn’t one of them. If you take anything else, check it against the full list below.

Moderate 76 No known interaction 2,754 (incl. Dexmethylphenidate)
Taking anything else?

Check Another of Your Medications Against Canadian Hemp

Covers the 2,830 medications we’ve checked against Canadian Hemp. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Canadian Hemp and Dexmethylphenidate May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. 2 of them are worth acting on rather than waiting out — marked below.

  • A slow heartbeat / Raised blood pressure Worth acting on Additional detail

    Canadian Hemp

    “Orally, Canadian hemp can cause digitalis-like toxicity due to its cardiac glycoside constituents. Symptoms of toxicity can include bradycardia with hypotension, increased heart contractions, and reflex hypertension. Canadian hemp can also cause topical irritation of the gastrointestinal mucous membranes.”

    Canadian Hemp · Natural Medicines adverse-effect record, reported in hypertension.

    1 source cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

    “Orally, Canadian hemp might cause bradycardia with low blood pressure, increased heart contractions, and reflex hypertension (18).”

    Canadian Hemp · Natural Medicines adverse-effect record, reported in hypertension.

    1 source cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

    Dexmethylphenidate

    Listed in the ADVERSE REACTIONS section of the FDA label for Dexmethylphenidate. Read the label on DailyMed ›

  • Vomiting / Nausea Additional detail

    Canadian Hemp

    “Orally, Canadian hemp can cause topical irritation of the gastrointestinal mucous membranes. This irritation can result in a higher incidence of nausea and vomiting than with other cardiac glycoside-containing plants (such as digitalis) (18).”

    Canadian Hemp · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    1 source cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.

    Dexmethylphenidate

    Listed in the ADVERSE REACTIONS section of the FDA label for Dexmethylphenidate. Read the label on DailyMed ›

Reported for Canadian Hemp but not commonly for Dexmethylphenidate: low blood pressure.

Effects for Dexmethylphenidate come from the ADVERSE REACTIONS section of its FDA label; effects for Canadian Hemp come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Canadian Hemp in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Unsafe

When used orally due to the toxic potential of its cardiac glycoside constituents; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Canadian Hemp or Dexmethylphenidate

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Canadian Hemp or Dexmethylphenidate, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Dexmethylphenidate

This page covers Canadian Hemp only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dexmethylphenidate page lists 85 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Lithium (major), Peyote (major) and Rauvolfia Vomitoria (major).

By severity: 6 major · 64 moderate · 15 minor.

From our pharmacist’s overview on the Dexmethylphenidate page

“Dexmethylphenidate (Focalin) is itself a prescription stimulant for ADHD, which is exactly why this list deserves real care rather than a quick skim. More than half of the 85 ingredients on file stimulate the nervous system too, so combining them can compound the racing heart, raised blood pressure, and sleeplessness the drug can alrea…”

Reviewed by 2 · Jul 18, 2026

Open the Dexmethylphenidate interaction page

How much people look this up

Where Canadian Hemp and Dexmethylphenidate 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 Canadian Hemp
Top half

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

29 days ago today
Medication Dexmethylphenidate
Top 25%

#425 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Canadian Hemp reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified October 4, 2026. The Canadian Hemp and Dexmethylphenidate records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Canadian Hemp

What is Canadian Hemp?

  • Heart-related swelling (dropsy/edema)
  • Fluid retention
  • Constipation
  • Urinary problems
  • Traditional folk remedy uses

Canadian Hemp (Apocynum cannabinum) is a toxic North American plant historically used as a heart stimulant and diuretic, but it contains potent cardiac glycosides that can cause dangerous heart and poisoning effects. It is not a safe or recommended dietary supplement, and there is no reliable modern evidence supporting its use. Avoid using it and talk to a pharmacist or doctor about safer, proven options.

Apocynum cannabinum · Apocynaceae · Dried roots and rhizomes · Tincture, dried root, traditional decoction (rarely sold as a modern supplement)

An interaction check asks whether these two react with each other — it does not ask whether Canadian Hemp is a good idea for someone in your situation. Here is what our Canadian Hemp record says about it on its own.

Canadian Hemp: dosing

There is no established safe dose for Canadian Hemp, and we do not provide one. Because it contains potent and potentially deadly heart-acting compounds with a very narrow safety margin, no general dosing guidance can be given.If you come across a product containing Apocynum cannabinum, do not take it without speaking to a pharmacist or doctor first. In nearly all cases, safer and better-studied options are available.

From our Canadian Hemp monograph — the full record covers uses, side effects and every documented interaction.

Read the full Canadian Hemp monograph & all interactions
Medication

About Dexmethylphenidate

What Is Dexmethylphenidate Used For?

Brand name: Focalin

Dexmethylphenidate treats attention deficit hyperactivity disorder (ADHD). Every product in this group is approved for that use: dexmethylphenidate tablets, Focalin tablets, dexmethylphenidate extended-release capsules and Focalin XR extended-release capsules.

The extended-release capsules (dexmethylphenidate and Focalin XR) are not recommended for children younger than 6 years. In that age group, blood levels were higher and side effects such as weight loss were more common.

See full Dexmethylphenidate drug information
Keep checking

Other Drugs & Canadian Hemp

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

0Major
76Moderate
0Minor
2,753No known interaction
76 Moderate 2,753 No interaction
Moderate

76 interactions

Showing 60 of 76 moderate interactions — see all 76 on the Canadian Hemp page.

No interaction 2,753 drugs checked — show the list

We also checked Canadian Hemp against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,753 medications checked with no known interaction — see the full Canadian Hemp list.

See the full Canadian Hemp interactions page
See every supplement checked against Dexmethylphenidate, ranked by severity
Evidence & sources

Canadian Hemp References

The 2 references that drive our Canadian Hemp monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Canadian Hemp and Dexmethylphenidate Together: Common Questions

Is it safe to take Canadian Hemp with Dexmethylphenidate?
We do not list a known interaction between Canadian Hemp and Dexmethylphenidate. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Canadian Hemp and Dexmethylphenidate have any of the same side effects?
Yes — our sources link each of them separately to 4 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
How was the Canadian Hemp and Dexmethylphenidate combination checked?
Interactions in our licensed database are recorded against drug classes. Dexmethylphenidate is filed under 5 classifications, and Canadian Hemp has documented interactions with 2 drug classes — none of Dexmethylphenidate's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Canadian Hemp interact with any other medications?
Yes. Canadian Hemp has 76 documented drug interactions in our database — Dexmethylphenidate is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Dexmethylphenidate interact with any supplements?
Yes. Dexmethylphenidate has documented interactions with 85 supplements in our database — Canadian Hemp is not one of them. The Dexmethylphenidate interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Canadian Hemp monograph Uses, safety profile, and every drug interaction in one place Dexmethylphenidate drug information The full plain-English guide to this medication Dexmethylphenidate supplement interactions Every supplement checked against Dexmethylphenidate, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 2 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Dexmethylphenidate and Canadian Hemp?

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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.