Herb & supplement monograph

Oleander Drug Interactions, Uses, Effectiveness, Safety & More

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

What is this page for?

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

But these pages have grown well beyond that into a full monograph — what Oleander 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

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On this page

Oleander Drug Interactions: The Bottom Line

From the HelloPharmacist Editorial Team · Updated July 2026

Based on the available evidence, the risk of a clinically significant Oleander drug interaction is high, because most of its known interactions are rated major and involve the heart. The large majority of listed interactions are major, none are minor, and the concerns center on oleander's naturally occurring heart-active compounds, which act much like the heart medicine digoxin.

Interactions deserving the most attention

The most serious concern is combining oleander with digoxin, since oleander contains very similar heart-active compounds and the effects could add together, raising the chance of toxicity. Potassium-depleting diuretics also stand out, because low potassium makes these heart-active compounds more dangerous, and overused stimulant laxatives can do the same. Certain antibiotics, such as macrolides and tetracyclines, and quinine may raise the amount of oleander's compounds the body absorbs or retains, which could also increase toxicity.

What the rest of the list means

Oleander interacts with a large number of medications, but most of these predictions come from how similar drugs like digoxin behave rather than direct human studies of oleander itself. Even so, because oleander's compounds affect the heart and have a narrow margin of safety, these theoretical risks are taken seriously rather than dismissed.

Check your medications against Oleander

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

Interaction report

Drugs that interact with Oleander

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

133 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 Oleander.

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

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

AI summaries are generated from our Oleander 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 Oleander 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 Oleander affects

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

All 7 drug categories Oleander interacts with

Digoxin (lanoxin)Diuretic DrugsMacrolide AntibioticsQuinineStimulant LaxativesTetracycline AntibioticsCorticosteroids

Digoxin (Lanoxin)

Theoretically, concomitant use of digoxin and oleander will increase the risk and severity of toxic effects.
Oleander contains cardiac glycosides similar to digoxin, increasing the risk of additive effects with concomitant use.

Likelihood Probable Evidence D

Diuretic Drugs

Theoretically, diuretic drugs may increase the risk of oleander toxicity.
Concomitant use of potassium depleting diuretics and oleander can increase the risk of cardiac glycoside toxicity due to potassium depletion.

Likelihood Probable Evidence D

Macrolide Antibiotics

Theoretically, macrolide antibiotics may increase the risk of oleander toxicity.
Macrolide antibiotics reduce levels of bacteria in the gut that break down digoxin to inactive metabolites, increasing digoxin bioavailability. Theoretically, this same process could increase the bioavailability of cardiac glycosides in oleander, increasing its toxicity.

Likelihood Probable Evidence D

Quinine

Theoretically, quinine may increase the risk of oleander toxicity.
Quinine is known to increase plasma levels of digoxin by inhibiting an efflux pump. This interaction might occur with other cardiac glycosides, including those in oleander.

Likelihood Probable Evidence D

Stimulant Laxatives

Theoretically, stimulant laxatives may increase the risk of oleander toxicity.
Overuse or misuse of stimulant laxatives leads to potassium depletion. This might increase the risk of toxicity with cardiac glycosides, including those in oleander.

Likelihood Probable Evidence D

Tetracycline Antibiotics

Theoretically, tetracycline antibiotics may increase the risk of oleander toxicity.
Tetracycline antibiotics reduce levels of bacteria in the gut that break down digoxin to inactive metabolites, increasing digoxin bioavailability. Theoretically, this same process might increase the bioavailability of cardiac glycosides in oleander, increasing its toxicity.

Likelihood Probable Evidence D

Corticosteroids

Theoretically, using oleander with prolonged corticosteroid therapy can increase the risk of oleander toxicity.
Oleander contains cardiac glycosides. Concomitant use of corticosteroids with oleander can increase the therapeutic and adverse effects of long-term corticosteroid use due to potassium depletion and electrolyte imbalance.

Likelihood Possible Evidence D

Monograph

Oleander: Uses, Safety & Side Effects

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

The bottom line

Oleander is a highly poisonous ornamental plant, and every part of it can cause life-threatening heart and nervous system effects, even in small amounts. There is no proven safe dose for self-use, and serious poisonings and deaths have occurred from teas, extracts, and accidental ingestion. We strongly advise against using oleander as a supplement.

Scientific name: Nerium oleander
Family: Apocynaceae
Part used: Leaves, flowers, stems, and seeds (all parts are toxic)
Common forms: Extracts, teas, and historically tinctures (not recommended for self-use)

People commonly use it for

Heart failure (traditional)
Cancer (investigational)
Skin conditions
Asthma (folk use)
Pain relief (folk use)

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

Safety at a glance

OverallBest avoided

Oleander is highly toxic and can be deadly even in small amounts.

PregnancyLikely Unsafe

When used orally. Oleander has been reported to have abortifacient properties. There is insufficient reliable information available about the safety o...

Read the full pregnancy detail

BreastfeedingLikely Unsafe

When used orally. Oleander has been reported to have abortifacient properties. There is insufficient reliable information available about the safety o...

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.

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Overview

Oleander (Nerium oleander) is an evergreen shrub with showy pink, white, or red flowers. It is widely planted as an ornamental in warm regions, including the southern United States, the Mediterranean, and parts of Asia and Africa.

Despite its beauty, oleander is one of the most poisonous common garden plants. Every part of the plant — leaves, flowers, stems, seeds, and even the sap — contains powerful toxins. People have historically used oleander in folk medicine and some have promoted oleander extracts as remedies, but it is dangerous and not a safe over-the-counter supplement.

How it works

Oleander contains cardiac glycosides, including compounds such as oleandrin. These chemicals act on the heart in a way similar to the prescription drug digoxin. They can affect the way heart muscle cells handle certain minerals, which changes how the heart beats.

At the wrong dose — which can be very small — these compounds cause dangerous heart rhythm changes and can stop the heart. Some laboratory studies have looked at oleandrin's effects on cells, but these early findings do not make the whole plant safe to swallow. The same chemistry that interests researchers is what poisons people.

Effectiveness

Does Oleander work?

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

Evidence overview · 10 uses evaluated

10 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.

For Oleander, current evidence isn’t strong enough to rate any specific use. The conditions it has been studied for are listed below.

Also studied for 10 conditions — evidence insufficient to rate

Insufficient Reliable Evidence To Rate Abortion