Drug & supplement interaction

Guarana + Doripenem

Doripenem brand name: Doribax.

Minor Interaction
The bottom line Minor

Guarana has a minor interaction with Doripenem. Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.

Read the full interaction report
SeverityMinor
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Guarana and Doripenem

Here is the interaction we found between these two, with the evidence behind it.

Minor

QUINOLONE ANTIBIOTICS

Why this applies to Doripenem

Doripenem falls under QUINOLONE ANTIBIOTICS — the group Guarana interacts with.

Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
Guarana contains caffeine. Theoretically, concomitant use might increase serum caffeine concentrations and the risk of adverse effects. Quinolones (also called fluoroquinolones) can decrease caffeine clearance by inhibiting the cytochrome P450 1A2 enzyme.
Severity Minor Likelihood Possible Evidence B

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 honest scoop on this one. The interaction in our database was written for quinolone antibiotics (like ciprofloxacin), which can slow down how your body clears caffeine through a liver enzyme called CYP1A2. That can let caffeine pile up and make you jittery. But doripenem (Doribax) is a different kind of antibiotic, a carbapenem, not a quinolone. It is not a prodrug, and it does not block that caffeine enzyme the way quinolones do.

So the caffeine in guarana is unlikely to interact with doripenem in any meaningful way. Just keep in mind that guarana is basically concentrated caffeine, so big doses can still cause a racing heart, anxiety, or trouble sleeping on their own. If you're unsure, check with your pharmacist.

References
  1. Harder S, Fuhr U, Staib AH, Wolff T. Ciprofloxacin-caffeine: a drug interaction established using in vivo and in vitro investigations. Am J Med 1989;87:89S-91S. PubMed
  2. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  3. Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. PubMed
  4. Staib, A. H., Stille, W., Dietlein, G., Shah, P. M., Harder, S., Mieke, S., and Beer, C. Interaction between quinolones and caffeine. Drugs 1987;34 Suppl 1:170-174. PubMed
  5. Stille, W., Harder, S., Mieke, S., Beer, C., Shah, P. M., Frech, K., and Staib, A. H. Decrease of caffeine elimination in man during co-administration of 4-quinolones. J.Antimicrob.Chemother. 1987;20(5):729-734. PubMed
  6. Fuhr, U., Strobl, G., Manaut, F., Anders, E. M., Sorgel, F., Lopez-de-Brinas, E., Chu, D. T., Pernet, A. G., Mahr, G., Sanz, F., and . Quinolone antibacterial agents: relationship between structure and in vitro inhibition of the human cytochrome P450 isof

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

Guarana Also Interacts With Other Medications

Guarana has 8 major, 462 moderate, 184 minor known drug interactions in our database — the Doripenem one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Guarana

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

Everything else you take

See Every Supplement That Interacts With Doripenem

This page covers Guarana only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Doripenem page lists 84 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Oleander (major), Para-aminobenzoic Acid (paba) (major), Acerola (moderate), Alpha-lipoic Acid (moderate) and Bacillus Coagulans (moderate).

By severity: 2 major · 75 moderate · 7 minor.

From our pharmacist’s overview on the Doripenem page

“Two entries here matter more than all the others, and I would read them first. Doripenem (Doribax) is an intravenous antibiotic reserved for serious bacterial infections, which means anything that weakens treatment or piles on risk deserves genuine caution.”

Reviewed by 2 · Jul 18, 2026

Open the Doripenem interaction page

One more smart check

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

We hold 1,430 real supplement products containing Guarana, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Guarana. Your product may carry other ingredients that interact with Doripenem too, on top of Guarana — 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 Guarana and Doripenem 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 Guarana
Top 10%

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

29 days ago today
Medication Doripenem
Steady interest

#2,547 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 Guarana

What is Guarana?

Guarana
  • Energy and alertness
  • Reducing fatigue
  • Weight loss support
  • Athletic performance
  • Mental focus

Guarana is an Amazonian seed that is naturally high in caffeine, which explains most of its stimulant and energy effects. While it may give a short-term boost in alertness and reduce fatigue, strong evidence for weight loss or major performance gains is limited, and it carries the same risks as too much caffeine. Talk to your pharmacist or doctor before using it, especially if you have heart problems, anxiety, or are pregnant.

Read the full Guarana monograph & all interactions
Medication

About Doripenem Injection

What Is Doripenem Injection Used For?

Brand name: Doribax

  • Doripenem injection is used to treat serious infections of the urinary tract, kidney, and abdomen that are caused by bacteria. Doripenem injection is not approved by the Food and Drug Administration (FDA) to treat pneumonia that developed in people who were on a ventilator in a hospital. Doripenem injection is in a class of medications called carbapenem antibiotics. It works by killing bacteria.

  • Antibiotics such as doripenem injection will not work for colds, flu, or other viral infections. Taking antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.

See full Doripenem Injection drug information
Keep checking

Other Drugs & Guarana

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

8Major
462Moderate
184Minor
2,175No known interaction
Major

8 interactions

Moderate

462 interactions

Showing 60 of 462 moderate interactions — see all 462 on the Guarana page.

Minor

184 interactions

Showing 60 of 184 minor interactions — see all 184 on the Guarana page.

No interaction 2,175 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Guarana and Doripenem Together: Common Questions

Can you take Guarana with Doripenem?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Guarana and Doripenem interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Doripenem and Guarana?

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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.