Herb & supplement monograph

Foxglove Drug Interactions, Uses, Effectiveness, Safety & More

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS ·Updated July 2026

What is this page for?

First and foremost: how Foxglove interacts with medications. The heart of this page is the interaction list — every drug Foxglove is known to interact with, and how serious each one is.

But these pages have grown well beyond that into a full monograph — what Foxglove is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy

Check Foxglove against your medication

Add one medication

✓ Supplement

Foxglove

1 Your medication

Start typing any prescription or over-the-counter drug name.

Reviewed by licensed pharmacists Sourced from Natural Medicines

On this page

Foxglove Drug Interactions: The Bottom Line

From the HelloPharmacist Editorial Team · Updated July 2026

Based on the available evidence, Foxglove drug interactions carry a genuinely elevated risk, because this plant naturally contains cardiac glycosides, the same class of compounds found in heart medications. Its interaction list includes major concerns, and nearly everything on it is rated moderate rather than minor, all tied to the risk of cardiac glycoside toxicity.

Interactions deserving the most attention

The clearest danger is with digoxin: foxglove actually contains digoxin and related compounds, so taking the two together is considered contraindicated and can push levels into the toxic range. Quinine is also a well-supported concern, since it can slow the body's clearance of cardiac glycosides. Potassium-depleting diuretics deserve attention too, because low potassium makes glycoside toxicity more likely, and the same logic applies to overuse of stimulant laxatives.

What the rest of the list means

The long list of moderate interactions looks daunting, but most reflect one shared theoretical concern rather than dozens of separate proven problems. Medicines like macrolide and tetracycline antibiotics are flagged because they might raise glycoside levels by changing absorption or elimination, effects predicted from how these drugs work rather than confirmed in people.

Check your medications against Foxglove

Based on HelloPharmacist’s Foxglove interaction data and reviewed under our editorial standards.

Interaction report

Drugs that interact with Foxglove

133 medications have a known interaction with Foxglove, graded by severity. Select any drug for the full evidence-based detail.

3 major interactions. These combinations can be clinically significant — best avoided, or used only with close professional supervision. Always check with your pharmacist before combining them with Foxglove.

Don’t want to scroll the list? Just ask.

Tell us the medications you take and we’ll check each one against Foxglove using our pharmacist-reviewed interaction data.

AI summaries are generated from our Foxglove interaction data for education only — always confirm with your pharmacist. How we use AI

2,830 drugs

Read The List Like a Pharmacist

What Severity, Likelihood & Evidence Mean

Severity — How Serious It Can Be

Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
No known interaction. Checked against our sources with nothing documented — not the same as proven safety.

Likelihood — How Well It’s Documented

Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
Probable. Interaction 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.
Possible. 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
Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

Where This Data Comes From

Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
Each drug listed above links to the full report for that exact Foxglove combination — clinical detail, likelihood, evidence level, and citations.
Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

The big picture

The kinds of drugs Foxglove affects

Every type of medication (drug category) Foxglove is known to interact with. Open any category for the detail — or search your exact drug in the checker above.

All 6 drug categories Foxglove interacts with

Digoxin (lanoxin)QuinineDiuretic DrugsMacrolide AntibioticsStimulant LaxativesTetracycline Antibiotics

Digoxin (Lanoxin)

Concomitant use of digoxin is contraindicated.
Foxglove contains varied cardiac glycosides, including digoxin Taking foxglove and digoxin concomitantly increases the risk of cardiac glycoside toxicity.

Likelihood Likely Evidence D

Quinine

Theoretically, concomitant use of quinine increases the risk of cardiac glycoside toxicity.
Foxglove contains varied cardiac glycosides, including digoxin. Quinine can reduce the elimination of some cardiac glycosides.

Likelihood Probable Evidence D

Diuretic Drugs

Theoretically, concomitant use of potassium depleting diuretics increases the risk of cardiac glycoside toxicity.
Foxglove contains varied cardiac glycosides, including digoxin. Hypokalemia increases the risk of cardiac glycoside toxicity.

Likelihood Possible Evidence D

Macrolide Antibiotics

Theoretically, concomitant use of macrolide antibiotics increases the risk of cardiac glycoside toxicity.
Foxglove contains varied cardiac glycosides, including digoxin. Macrolide antibiotics can the reduce elimination of some cardiac glycosides.

Likelihood Possible Evidence D

Stimulant Laxatives

Theoretically, overuse of stimulant laxatives increases the risk of cardiac glycoside toxicity.
Foxglove contains varied cardiac glycosides, including digoxin. Hypokalemia, which may be caused by overuse of stimulant laxative, increases the risk of cardiac glycoside toxicity.

Likelihood Possible Evidence D

Tetracycline Antibiotics

Theoretically, concomitant use of quinine increases the risk of cardiac glycoside toxicity.
Foxglove contains varied cardiac glycosides, including digoxin. Tetracycline can increase oral absorption of some cardiac glycosides.

Likelihood Possible Evidence D

Monograph

Foxglove: Uses, Safety & Side Effects

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Reviewed July 2026 ·

The bottom line

Foxglove is a beautiful but highly poisonous plant that contains powerful heart-affecting compounds called cardiac glycosides. It should never be used as a home remedy or supplement because even small amounts can cause life-threatening heart problems. The purified prescription drugs derived from it (like digoxin) are used only under close medical supervision.

Scientific name: Digitalis purpurea
Family: Plantaginaceae
Part used: Leaves (the dried leaf was historically the source of medicine)
Common forms: Not recommended in any form; historically used as dried leaf, tincture, or purified drug (digoxin/digitoxin)

People commonly use it for

Heart failure (historical/medical use)
Irregular heartbeat (historical/medical use)
Fluid retention or 'dropsy' (historical use)
Ornamental garden plant

Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.

Safety at a glance

OverallBest avoided

Foxglove is poisonous and can cause fatal heart rhythm problems; it should never be self-used.

PregnancyUnsafe

When used orally for self-medication; avoid using.

Read the full pregnancy detail

BreastfeedingUnsafe

When used orally for self-medication; avoid using.

Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Jump to a section

Overview

Foxglove is a tall flowering plant with bell-shaped purple, pink, or white blooms. It is common in gardens and grows wild across parts of Europe and North America. While it is admired for its beauty, every part of the plant is poisonous.

Foxglove leaves contain natural chemicals called cardiac glycosides. Centuries ago, healers used dried foxglove leaf to treat people with swelling and heart problems. Today, scientists have isolated and purified some of these chemicals into carefully controlled prescription medicines, but the raw plant itself is not used as a supplement or home remedy.

How it works

The main active compounds in foxglove are cardiac glycosides, including digoxin and digitoxin. These chemicals affect how the heart muscle contracts and how electrical signals move through the heart.

In carefully controlled medical doses, this can help certain hearts pump more strongly and beat more steadily. But the gap between a helpful amount and a harmful amount is very small. Even slightly too much can disturb the heart's rhythm in dangerous, sometimes deadly ways. This is why foxglove cannot be safely dosed at home.

Effectiveness

Does Foxglove work?

Here’s what the research actually shows for each use — graded by Natural Medicines and reviewed by Dr. Brian Staiger, PharmD.

Evidence overview · 9 uses evaluated

2 Possibly effective 7 Insufficient evidence

How to read these evidence grades

Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.

1EffectiveStrong, consistent evidence it works.

2Likely EffectiveGood evidence, though not yet conclusive.

3Possibly EffectiveSome evidence suggests a benefit.

4Possibly IneffectiveSome evidence it may not help.

5Likely IneffectiveFairly strong evidence it doesn’t help.

6IneffectiveStrong evidence it doesn’t work.

7Insufficient Reliable Evidence to RateToo little research to say either way.

Possibly Effective Atrial fibrillation