Drug & supplement interaction

Oleander + Tigecycline

Tigecycline brand name: Tygacil.

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

Tigecycline falls into 2 drug categories that Oleander can interact with; the most serious is rated major. Theoretically, macrolide antibiotics may increase the risk of oleander toxicity.

Read the full interaction report
SeverityMajor
LikelihoodProbable
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Oleander and Tigecycline

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Oleander interacts with whole categories of medication. Tigecycline falls into 2 of those categories, so it can interact with Oleander in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Major).

Major

MACROLIDE ANTIBIOTICS

1 of 2

Why this applies to Tigecycline

Tigecycline falls under MACROLIDE ANTIBIOTICS — the group Oleander interacts with.

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.
Severity Major Likelihood Probable Evidence D

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..

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

First, the big picture: oleander is genuinely dangerous, and I'd urge you not to use it at all. It contains heart-acting chemicals (cardiac glycosides) that behave a lot like digoxin, and even tiny amounts can trigger life-threatening heart rhythm problems.

Now for the combo. The concern on file is mostly theoretical, based on how the body handles these drugs. Certain antibiotics can lower gut bacteria that normally break down digoxin-like compounds, so more of oleander's toxin may get absorbed. Tigecycline isn't a prodrug, and it's a tetracycline rather than a true macrolide, so the link here is even less certain. Still, both being antibiotics that disturb gut bacteria, I'd stay cautious. The real takeaway: don't use oleander, and tell your doctor or pharmacist about everything you take.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
Major

TETRACYCLINE ANTIBIOTICS

2 of 2

Tigecycline also falls under 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.
Severity Major Likelihood Probable Evidence D

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..

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

First and most important: oleander is genuinely poisonous, and we don't recommend using it at all. Setting that aside, here's how it could mix with your tigecycline (Tygacil). Some of the heart-acting chemicals in oleander get broken down by bacteria living in your gut. Tigecycline is a tetracycline-type antibiotic, so along with fighting your infection it can knock down some of those gut bacteria.

With fewer of those bacteria around, more of the oleander toxin could end up in your bloodstream, raising the risk of dangerous effects like an irregular or slowed heartbeat, nausea, and vomiting. This concern is theoretical and based on how these drugs behave, not on solid studies, but the stakes are high. Please don't take oleander, and talk with your pharmacist or doctor about any supplements you're using.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.

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

Oleander Also Interacts With Other Medications

Oleander has 132 major, 23 moderate known drug interactions in our database — the Tigecycline one above is among them. If you take anything else, check it against the full list below.

Major 132 Moderate 23 No known interaction 2,675 (incl. Tigecycline)
Taking anything else?

Check Another of Your Medications Against Oleander

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

Everything else you take

See Every Supplement That Interacts With Tigecycline

This page covers Oleander only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tigecycline page lists 98 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Para-aminobenzoic Acid (paba) (major), Acerola (moderate), Alfalfa (moderate), Alpha-lipoic Acid (moderate) and Angelica Archangelica (moderate).

By severity: 2 major · 88 moderate · 8 minor.

From our pharmacist’s overview on the Tigecycline page

“Tigecycline (Tygacil) is an intravenous antibiotic usually reserved for serious or resistant infections, and its supplement list deserves real attention. The two major-rated entries come first: oleander, a heart-toxic plant whose compounds may build to dangerous levels with certain antibiotics on board, and PABA, which can blunt the an…”

Reviewed by 2 · Jul 18, 2026

Open the Tigecycline interaction page

How much people look this up

Where Oleander and Tigecycline 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 Oleander
Top half

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

29 days ago today
Medication Tigecycline
Steady interest

#2,419 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 Oleander

What is Oleander?

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

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.

Read the full Oleander monograph & all interactions
Medication

About Tigecycline Injection

What Is Tigecycline Injection Used For?

Brand name: Tygacil

Tigecycline Injection (brand: Tygacil) treats certain serious bacterial infections in adults 18 and older. It is used for complicated skin and skin structure infections, complicated intra-abdominal (belly) infections, and community-acquired bacterial pneumonia.

It is not approved for diabetic foot infections or for hospital-acquired pneumonia, including ventilator-associated pneumonia. It works only against bacteria, not viruses.

See full Tigecycline Injection drug information
Keep checking

Other Drugs & Oleander

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

132Major
23Moderate
0Minor
2,674No known interaction
132 Major 23 Moderate 2,674 No interaction
Major

132 interactions

Showing 60 of 132 major interactions — see all 132 on the Oleander page.

Moderate

23 interactions

No interaction 2,674 drugs checked — show the list

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

Showing the 60 most looked-up of 2,674 medications checked with no known interaction — see the full Oleander list.

See the full Oleander interactions page
See every supplement checked against Tigecycline, 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
Oleander monograph › Uses, safety, and every drug interaction in one place Tigecycline supplement interactions › Every supplement checked against Tigecycline, ranked by severity Tigecycline Injection 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 Oleander and Tigecycline Together: Common Questions

Can you take Oleander with Tigecycline?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Oleander and Tigecycline?
Tigecycline belongs to more than one drug category, and Oleander interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Oleander and Tigecycline interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

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

Still Have a Question About Tigecycline and Oleander?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.