Drug & supplement interaction

Ephedra + Levofloxacin

Levofloxacin brand names: Levaquin, Levaquin Injection, Leva-pak.

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

Levofloxacin falls into 2 drug categories that Ephedra can interact with; the most serious is rated major. Theoretically, ephedra might have an additive effect with drugs that prolong the QT interval.

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

Ephedra and Levofloxacin

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

Why Are There 2 Interactions?

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

Major

QT INTERVAL-PROLONGING DRUGS

1 of 2

Why this applies to Levofloxacin

Levofloxacin falls under QT INTERVAL-PROLONGING DRUGS — the group Ephedra interacts with.

Theoretically, ephedra might have an additive effect with drugs that prolong the QT interval.
Even in healthy volunteers, EKG changes including prolonged QT interval and premature atrial contractions have been reported with ingestion of recommended doses of ephedra. Ephedra may have an additive effect with drugs that prolong the QT interval. This may increase the risk of ventricular arrhythmias.
Severity Major Likelihood Probable Evidence B

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

Here's the concern with this combo. Levofloxacin is an antibiotic that can stretch out the heart's electrical reset time, something doctors call QT prolongation. Ephedra, with its stimulant compounds like ephedrine, can do the same thing and also speed up your heart and raise your blood pressure. Stacking the two together adds up, and that can raise the risk of a dangerous irregular heartbeat.

This worries me even more because ephedra is banned in U.S. supplements for serious heart-related harms. Levofloxacin isn't a prodrug here, so this isn't about how the drug is broken down, it's about both nudging your heart rhythm in the same risky direction. Please don't pair them. Talk with your pharmacist or doctor about safer options for whatever you're treating.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Jenkins DJ, Wesson V, Wolever TM, et al. Wholemeal versus wholegrain breads: proportion of whole or cracked grain and the glycaemic response. BMJ 1988;297:958-60. PubMed
  2. McBride BF, Karapanos AK, Krudysz A, et al. Electrocardiographic and hemodynamic effects of a multicomponent dietary supplement containing ephedra and caffeine: a randomized controlled trial. JAMA 2004;291:216-21. PubMed
  3. Gardner SF, Franks AM, Gurley BJ, et al. Effect of a multicomponent, ephedra-containing dietary supplement (Metabolife 356) on Holter monitoring and hemostatic parameters in healthy volunteers. Am J Cardiol 2003;91:1510-3, A9. PubMed
  4. Gardner, S. F., Franks, A. M., Gurley, B. J., Haller, C. A., Singh, B. K., and Mehta, J. L. Effect of a multicomponent, ephedra-containing dietary supplement (Metabolife 356) on Holter monitoring and hemostatic parameters in healthy volunteers. Am J Card PubMed
Moderate

HEPATOTOXIC DRUGS

2 of 2

Levofloxacin also falls under HEPATOTOXIC DRUGS.

Theoretically, concomitant use might have additive adverse hepatotoxic effects.
There are numerous cases of liver toxicity from ephedra-containing supplements.
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 concern with pairing ephedra and levofloxacin. Both have been linked, separately, to liver irritation. Ephedra supplements have caused real cases of liver injury, and levofloxacin (Levaquin) can occasionally stress the liver too. The worry is that using them together could add up and put extra strain on your liver.

To be honest, this is a theoretical concern based on how each one behaves, not solid proof that they collide. Still, watch for warning signs like yellowing skin or eyes, dark urine, belly pain on the right side, or unusual tiredness. Honestly, the bigger issue is that ephedra is banned in U.S. supplements and is risky on its own for your heart and blood pressure. Please talk with your pharmacist or doctor about safer options.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Nadir A, Agrawal S, King PD, Marshall JB. Acute hepatitis associated with the use of a Chinese herbal product, ma-huang. Am J Gastroenterol 1996;91:1436-8.
  2. Borum, M. L. Fulminant exacerbation of autoimmune hepatitis after the use of ma huang. Am J Gastroenterol. 2001;96(5):1654-1655. PubMed
  3. Vigano, M., Lampertico, P., and Colombo, M. Acute hepatitis following assumption of a herbal remedy. Eur.J.Gastroenterol.Hepatol. 2008;20(4):364-365. PubMed
  4. Neff, G. W., Reddy, K. R., Durazo, F. A., Meyer, D., Marrero, R., and Kaplowitz, N. Severe hepatotoxicity associated with the use of weight loss diet supplements containing ma huang or usnic acid. J Hepatol. 2004;41(6):1062-1064. PubMed
  5. Bajaj J, Knox JF, Komorowski R, Saeian K. The irony of herbal hepatitis: Ma-Huang-induced hepatotoxicity associated with compound heterozygosity for hereditary hemochromatosis. Dig Dis Sci. 2003;48(10):1925-8.
  6. Charalampopoulos A, Karatsourakis T, Tsiodra P. Acute hepatitis associated with the use of Ma-huang in a young adult. Eur J Intern Med. 2007;18(1):81. PubMed
  7. Skoulidis F, Alexander GJ, Davies SE. Ma huang associated acute liver failure requiring liver transplantation. Eur J Gastroenterol Hepatol. 2005;17(5):581-4. PubMed
  8. Drug record: Ma huang. U.S. National Library of Medicine: Livertox Database. https://livertox.nlm.nih.gov/Ephedra.htm. Updated October 16, 2017. Accessed November 1, 2017.

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

Ephedra Also Interacts With Other Medications

Ephedra has 336 major, 496 moderate known drug interactions in our database — the Levofloxacin one above is among them. If you take anything else, check it against the full list below.

Major 336 Moderate 496 No known interaction 1,998 (incl. Levofloxacin)
Taking anything else?

Check Another of Your Medications Against Ephedra

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

From our Q&A

Questions About Ephedra or Levofloxacin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Ephedra or Levofloxacin, 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 Levofloxacin

This page covers Ephedra only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Levofloxacin page lists 155 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Apple (major), Arsenic (major) and Asarabacca (major).

By severity: 13 major · 121 moderate · 21 minor.

From our pharmacist’s overview on the Levofloxacin page

“Levofloxacin (Levaquin) is a potent fluoroquinolone antibiotic, and its supplement list deserves real respect, with 13 of the 155 entries rated major. The most everyday hazards are fruit juices.”

Reviewed by 2 · Jul 18, 2026

Open the Levofloxacin interaction page

One more smart check

Taking Ephedra as Part of a Dietary Supplement Product? Check It for Interactions

We hold 37 real supplement products containing Ephedra, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Ephedra. Your product may carry other ingredients that interact with Levofloxacin too, on top of Ephedra — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Ephedra and Levofloxacin 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 Ephedra
Top half

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

29 days ago today
Medication Levofloxacin
Top 25%

#435 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 Ephedra

What is Ephedra?

Ephedra
  • Weight loss
  • Nasal and sinus congestion
  • Asthma and breathing problems
  • Boosting energy and athletic performance
  • Allergies

Ephedra (ma huang) contains powerful stimulants like ephedrine that affect the heart and nervous system. Because it has been linked to serious harms including high blood pressure, stroke, and death, it is banned for use in dietary supplements in the U.S. and many other countries. We do not recommend using ephedra-containing supplements; talk to your pharmacist or doctor about safer, approved options.

Read the full Ephedra monograph & all interactions
Medication

About Levofloxacin

What Is Levofloxacin Used For?

Brand names: Levaquin, Levaquin Injection, Leva-pak

Levofloxacin treats bacterial infections in adults, including pneumonia (both community-acquired and hospital-acquired), skin infections, urinary tract infections, kidney infections, chronic bacterial prostatitis, and sinus infections. It is also used after exposure to inhalational anthrax and for plague.

Because levofloxacin carries significant risks, it should only be used for uncomplicated urinary tract infections, acute bacterial worsening of chronic bronchitis, and acute bacterial sinusitis when no other treatment option is available. Always use it only for infections confirmed or strongly suspected to be bacterial.

See full Levofloxacin drug information
Keep checking

Other Drugs & Ephedra

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

336Major
496Moderate
0Minor
1,997No known interaction
336 Major 496 Moderate 1,997 No interaction
Major

336 interactions

Showing 60 of 336 major interactions — see all 336 on the Ephedra page.

Moderate

496 interactions

Showing 60 of 496 moderate interactions — see all 496 on the Ephedra page.

No interaction 1,997 drugs checked — show the list

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

Showing the 60 most looked-up of 1,997 medications checked with no known interaction — see the full Ephedra list.

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

Can you take Ephedra with Levofloxacin?
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 Ephedra and Levofloxacin?
Levofloxacin belongs to more than one drug category, and Ephedra 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 Ephedra and Levofloxacin 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 Levofloxacin and Ephedra?

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.