Drug & supplement interaction

Ilex Guayusa + Ivabradine

Ivabradine brand names: Procoralan, Coralan, Corlentor, Corlanor.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 27, 2026

The bottom line No known interaction

We found no known interaction between Ilex Guayusa and Ivabradine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Ivabradine states a food rule worth keeping to, and the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Ilex Guayusa and Ivabradine

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Ivabradine and Ilex Guayusa in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Ilex Guayusa safety at a glance

Ilex Guayusa overall Use caution Generally well tolerated in tea amounts, but it contains caffeine that can cause stimulant side effects.

Pregnancy Use caution Limit or avoid because of its caffeine content and a lack of safety studies in pregnancy.

Breastfeeding Use caution Caffeine passes into breast milk, so limit intake or avoid until more is known.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Ivabradine and Ilex Guayusa? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

How we checked

Why No Interaction Is Listed for Ivabradine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Ivabradine is filed under 3 classifications — including cytochrome p450 3a4 (cyp3a4) substrates, oral drugs. Ilex Guayusa has documented interactions with 37 drug classes — the most serious being ephedrine (major), adenosine (adenocard) (moderate) and anticoagulant/antiplatelet drugs (moderate) — and none of Ivabradine’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Ilex Guayusa Does Interact With Other Medications

Ilex Guayusa has 8 major, 470 moderate, 127 minor known drug interactions in our database — Ivabradine isn’t one of them. If you take anything else, check it against the full list below.

Major 8 Moderate 470 Minor 127 No known interaction 2,225 (incl. Ivabradine)

Taking anything else?

Check Another of Your Medications Against Ilex Guayusa

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

What to actually watch for

No Interaction Found — But Data Suggests Ilex Guayusa and Ivabradine May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

Raised blood pressure Worth acting on Additional detail
Ilex Guayusa
“Orally, a single dose of guayasa extract 600 mg or 1200 mg has been reported to increase systolic blood pressure by 4-6 mmHg and diastolic blood pressure by 2-5 mmHg on average in small clinical studies.

Although acute administration of caffeine, a constituent of Ilex guayusa, can cause increased blood pressure, regular consumption does not seem to increase either blood pressure or pulse, even in mildly hypertensive…”

Ilex Guayusa · Natural Medicines adverse-effect record, reported in hypertension.
6 sources cited

113625. La Monica MB, Raub B, Ziegenfuss EJ, et al. Acute effects of naturally occurring guayusa tea and Nordic lion's mane extracts on cognitive performance. Nutrients 2023;15(24):5018. PubMed

115148. Helwig NJ, Schwager LE, Berry AC, et al. Acute, dose-response effects of guayusa leaf extract on mood, cognitive and motor-cognitive performance, and blood pressure, heart rate, and ventricular repolarization. J Int Soc Sports Nutr 2024;21(1):2379424. PubMed

1451. Wakabayashi K, Kono S, Shinchi K, et al. Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan. Eur J Epidemiol 1998;14:669-73. PubMed

1452. Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63. PubMed

2722. Nurminen ML, Niittynen L, Korpela R, Vapaatalo H. Coffee, caffeine and blood pressure: a critical review. Eur J Clin Nutr 1999;53:831-9. PubMed

13739. Winkelmayer WC, Stampfer MJ, Willett WC, Curhan GC. Habitual caffeine intake and the risk of hypertension in women. JAMA 2005;294:2330-5. PubMed
Ivabradine

Listed in the ADVERSE REACTIONS section of the FDA label for Ivabradine. Read the label on DailyMed ›

Reported for Ilex Guayusa but not commonly for Ivabradine: trouble concentrating, dependence or withdrawal symptoms, low mood and anxiety or restlessness.

Effects for Ivabradine come from the ADVERSE REACTIONS section of its FDA label; effects for Ilex Guayusa come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

How to take them

Some Ivabradine Products Have a Food Rule — Ilex Guayusa Should Not Break It

At least one FDA label for a product containing Ivabradine says to take it with food. If you take Ilex Guayusa on an empty stomach out of habit, keep them separate — and take Ivabradine with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Ivabradine products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

DOSAGE AND ADMINIST R ATION Adult and pediatric patients greater than 40 kg Starting dose is 2.5 (pediatrics and vulnerable adults) or 5 mg twice daily with food.

From the Dosage and Administration section of the FDA label we read for Ivabradine — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

Everything else you take

See Every Supplement That Interacts With Ivabradine

This page covers Ilex Guayusa only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ivabradine page lists 138 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 94 moderate · 41 minor.

Open the Ivabradine interaction page

How much people look this up

Where Ilex Guayusa and Ivabradine 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 Ilex Guayusa

Steady interest

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

29 days ago today

Medication Ivabradine

Top half

#1,123 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.

Where does our data come from?

Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Ilex Guayusa reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 27, 2026. The Ilex Guayusa and Ivabradine records this page draws on were last updated July 10, 2026.
What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.

Data structure & sourcing designed and verified by Dr. Brian Staiger, PharmD, BCPS.

Supplement

About Ilex Guayusa

What is Ilex Guayusa?

Energy and alertness
Mental focus
Antioxidant support
Appetite control
Athletic and physical performance

Ilex guayusa is a caffeine-containing holly leaf from the Amazon, traditionally brewed as a tea for energy and alertness, much like yerba mate or green tea. There is limited human research confirming specific health benefits, and its main reliable effect comes from its caffeine content. Because it is a stimulant, use it cautiously and check with your pharmacist or doctor if you have heart concerns or are pregnant.

Ilex guayusa · Aquifoliaceae · Leaves · Tea, brewed infusion, capsules, powdered extract, energy drinks

An interaction check asks whether these two react with each other — it does not ask whether Ilex Guayusa is a good idea for someone in your situation. Here is what our Ilex Guayusa record says about it on its own.

Ilex Guayusa: dosing

There is no official standardized dose for guayusa. It is most commonly taken as a brewed tea, and the amount of caffeine you get can vary widely depending on how much leaf you use and how long you steep it.If you use a packaged product, follow the directions on the label and do not exceed the recommended serving. Keep your total daily caffeine from all sources in mind.

From our Ilex Guayusa monograph — the full record covers uses, side effects and every documented interaction.

Read the full Ilex Guayusa monograph & all interactions

Medication

About Ivabradine

What Is Ivabradine Used For?

Brand names: Procoralan, Coralan, Corlentor, Corlanor

Ivabradine is used for stable, symptomatic chronic heart failure in adults to reduce the risk of being hospitalized for worsening heart failure. It is for adults with a reduced ejection fraction (the heart's pumping strength is low, 35% or less), who are in normal sinus rhythm with a resting heart rate of 70 beats per minute or higher. They must also be on the highest beta-blocker dose they can tolerate, or be unable to take beta-blockers.

Corlanor (the brand) is also approved to treat stable, symptomatic heart failure due to dilated cardiomyopathy (a weakened, enlarged heart muscle) in children 6 months and older who are in sinus rhythm with an elevated heart rate. The generic ivabradine tablet labels list the adult use only.

See full Ivabradine drug information

Keep checking

Other Drugs & Ilex Guayusa

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

8Major

470Moderate

127Minor

2,224No known interaction

8 Major 470 Moderate 127 Minor 2,224 No interaction

Major

8 interactions

Moderate

470 interactions

Showing 60 of 470 moderate interactions — see all 470 on the Ilex Guayusa page.

Minor

127 interactions

Showing 60 of 127 minor interactions — see all 127 on the Ilex Guayusa page.

No interaction 2,224 drugs checked — show the list

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

Showing the 60 most looked-up of 2,224 medications checked with no known interaction — see the full Ilex Guayusa list.

See the full Ilex Guayusa interactions page

See every supplement checked against Ivabradine, ranked by severity

Evidence & sources

Ilex Guayusa References

The 90 references that drive our Ilex Guayusa monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

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Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63. PubMed
Rapuri PB, Gallagher JC, Kinyamu HK, Ryschon KL. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes. Am J Clin Nutr 2001;74:694-700. PubMed
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Dews PB, Curtis GL, Hanford KJ, O'Brien CP. The frequency of caffeine withdrawal in a population-based survey and in a controlled, blinded pilot experiment. J Clin Pharmacol 1999;39:1221-32. PubMed
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La Monica MB, Raub B, Ziegenfuss EJ, et al. Acute effects of naturally occurring guayusa tea and Nordic lion's mane extracts on cognitive performance. Nutrients 2023;15(24):5018. PubMed
Swanston-Flatt SK, Day C, Flatt PR, Gould BJ, Bailey CJ. Glycaemic effects of traditional European plant treatments for diabetes. Studies in normal and streptozotocin diabetic mice. Diabetes Res 1989;10(2):69-73.
Helwig NJ, Schwager LE, Berry AC, et al. Acute, dose-response effects of guayusa leaf extract on mood, cognitive and motor-cognitive performance, and blood pressure, heart rate, and ventricular repolarization. J Int Soc Sports Nutr 2024;21(1):2379424. PubMed
Mello TC, Dias DDS, Bernardes N, et al. Ilex Guayusa Tea Improves Glycaemia and Autonomic Modulation in Female Streptozotocin-Induced Diabetic Rats. Pharmaceuticals (Basel) 2025;18(3):316. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Ilex Guayusa and Ivabradine Together: Common Questions

Is it safe to take Ilex Guayusa with Ivabradine?

We do not list a known interaction between Ilex Guayusa and Ivabradine. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.

Do Ilex Guayusa and Ivabradine have any of the same side effects?

Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.

Should I take Ilex Guayusa and Ivabradine at the same time of day?

At least one FDA label for a product containing Ivabradine says to take it with food. If you take Ilex Guayusa on an empty stomach out of habit, keep them separate and take Ivabradine with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Ivabradine products can differ — so check the directions on your own box. This is about absorption, not an interaction.

How was the Ilex Guayusa and Ivabradine combination checked?

Interactions in our licensed database are recorded against drug classes. Ivabradine is filed under 3 classifications, and Ilex Guayusa has documented interactions with 37 drug classes — none of Ivabradine's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.

Does Ilex Guayusa interact with any other medications?

Yes. Ilex Guayusa has 605 documented drug interactions in our database — Ivabradine is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.

Does Ivabradine interact with any supplements?

Yes. Ivabradine has documented interactions with 138 supplements in our database — Ilex Guayusa is not one of them. The Ivabradine interaction page linked on this page lists every one, ranked by severity.

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

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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.