Drug & supplement interaction

Guarana + Insulin Lispro Recombinant

Insulin Lispro Recombinant brand name: Humalog Kwikpen.

Minor Interaction
The bottom line Minor

Guarana has a minor interaction with Insulin Lispro Recombinant. Theoretically, taking guarana with antidiabetes drugs might interfere with blood glucose control.

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

Guarana and Insulin Lispro Recombinant

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

Minor

ANTIDIABETES DRUGS

Why this applies to Insulin Lispro Recombinant

Insulin Lispro Recombinant falls under ANTIDIABETES DRUGS — the group Guarana interacts with.

Theoretically, taking guarana with antidiabetes drugs might interfere with blood glucose control.
Some conflicting reports claim that caffeine, a constituent of guarana, might increase or decrease blood sugar.
Severity Minor Likelihood Unlikely Evidence B

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

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

Here's the bottom line on pairing guarana with your Humalog (insulin lispro): the caffeine in guarana can have a small, unpredictable effect on your blood sugar. Some reports suggest caffeine nudges blood sugar up, others suggest it can lower it, so the direction isn't consistent. This is rated a minor and unlikely interaction, and the evidence behind it is fairly weak.

Practically speaking, the bigger concern is just being a bit less sure where your numbers will land on a given day. Since insulin lispro acts fast and a sudden drop can cause shakiness, sweating, confusion, or a low (hypoglycemia), it's smart to check your readings more closely if you start using guarana regularly. An occasional cup of something caffeinated is unlikely to matter much, but concentrated supplement doses could. Loop in your pharmacist or doctor before adding it.

References
  1. Watson JM, Jenkins EJ, Hamilton P, et al. Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes. Diabetes Care 2000;23:455-9. PubMed
  2. Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001;33:1399-403. PubMed

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 Insulin Lispro Recombinant 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 Insulin Lispro Recombinant

This page covers Guarana only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Insulin Lispro Recombinant page lists 242 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Chelation Therapy Products (major), Siberian Cocklebur (major), Acai (moderate), African Wild Potato (moderate) and Agaricus Mushroom (moderate).

By severity: 2 major · 211 moderate · 29 minor.

From our pharmacist’s overview on the Insulin Lispro Recombinant page

“Two of the 242 entries here rate major, and they are the place to start. Siberian cocklebur has caused severe hypoglycemia, and chelation products containing EDTA can drop blood glucose steeply while also interfering with the insulin itself, so neither belongs anywhere near insulin lispro (Humalog KwikPen).”

Reviewed by 2 · Jul 18, 2026

Open the Insulin Lispro Recombinant 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 Insulin Lispro Recombinant 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 Insulin Lispro Recombinant 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%

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

29 days ago today
Medication Insulin Lispro Recombinant
Steady interest

#2,077 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
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 Insulin Lispro Recombinant Together: Common Questions

Can you take Guarana with Insulin Lispro Recombinant?
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 Insulin Lispro Recombinant 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 Insulin Lispro Recombinant 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.