Drug & supplement interaction

Ilex Guayusa + Clofazimine

Clofazimine brand name: Lamprene.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 20, 2026

The bottom line No known interaction

We found no known interaction between Ilex Guayusa and Clofazimine 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 Clofazimine 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 Clofazimine

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 Clofazimine 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 Clofazimine and Ilex Guayusa? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

How we checked

Why No Interaction Is Listed for Clofazimine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Clofazimine is filed under 3 classifications — antibiotic drugs, photosensitizing drugs, 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 Clofazimine’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 — Clofazimine 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. Clofazimine)

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 Clofazimine May Share Several of the Same Side Effects

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.

Low mood Worth acting on Additional detail
Ilex Guayusa
“Chronic use of caffeine, especially in large amounts, may produce tolerance, habituation, and psychological dependence. There is some concern that stopping regular use of caffeine may cause withdrawal symptoms such as headache, tiredness and fatigue, decreased energy, alertness, and attentiveness, drowsiness, decreased contentedness, depressed mood, difficulty concentrating, irritability, and lack of clear-headedness…”

Ilex Guayusa · Natural Medicines adverse-effect record, reported in anxiety.
5 sources cited

3719. Boozer CN, Nasser JA, Heymsfield SB, et al. An herbal supplement containing Ma Huang-Guarana for weight loss: a randomized, double-blind trial. Int J Obes Relat Metab Disord 2001;25:316-24. PubMed

13738. Juliano LM, Griffiths RR. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology (Berl) 2004;176:1-29. PubMed

2723. 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

11839. Dews PB, O'Brien CP, Bergman J. Caffeine: behavioral effects of withdrawal and related issues. Food Chem Toxicol 2002;40:1257-61. PubMed

13736. Anderson BJ, Gunn TR, Holford NH, Johnson R. Caffeine overdose in a premature infant: clinical course and pharmacokinetics. Anaesth Intensive Care 1999;27:307-11. PubMed
Clofazimine

Listed in the ADVERSE REACTIONS section of the FDA label for Clofazimine. Read the label on DailyMed ›
Drowsiness / Tiredness / Headache Additional detail

Ilex Guayusa

Recorded for Ilex Guayusa in the same Natural Medicines adverse-effect record shown under Low mood above.

Clofazimine

Listed in the ADVERSE REACTIONS section of the FDA label for Clofazimine. Read the label on DailyMed ›
Swelling Additional detail
Ilex Guayusa
“Some evidence shows that caffeine, a constituent of Ilex guayusa, is associated with fibrocystic breast disease, breast cancer, and endometriosis in females; however, this is controversial since findings are conflicting. Restricting caffeine in females with fibrocystic breast conditions doesn't seem to affect breast nodularity, swelling, or pain.”

Ilex Guayusa · Natural Medicines adverse-effect record, reported in breast cancer.
5 sources cited

8043. Ferrini RL, Barrett-Connor E. Caffeine intake and endogenous sex steroid levels in postmenopausal women. The Rancho Bernardo Study. Am J Epidemiol 1996:144:642-4. PubMed

8996. Horner NK, Lampe JW. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness. J Am Diet Assoc 2000;100:1368-80. PubMed

108806. Zheng KH, Zhu K, Wactawski-Wende J, et al. Caffeine intake from coffee and tea and invasive breast cancer incidence among postmenopausal women in the Women's Health Initiative. Int J Cancer 2021;149(12):2032-2044. PubMed

108807. Wang S, Li X, Yang Y, et al. Does coffee, tea and caffeine consumption reduce the risk of incident breast cancer? A systematic review and network meta-analysis. Public Health Nutr 2021;24(18):6377-6389. PubMed

91023. Beaudoin MS, Allen B, Mazzetti G, Sullivan PJ, Graham TE. Caffeine ingestion impairs insulin sensitivity in a dose-dependent manner in both men and women. Appl Physiol Nutr Metab. 2013;38(2):140-7. doi: 10.1139/apnm-2012-0201. Epub 2012 9. PubMed
Clofazimine

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

Reported for Ilex Guayusa but not commonly for Clofazimine: trouble concentrating, dependence or withdrawal symptoms, raised blood pressure and anxiety or restlessness.

Effects for Clofazimine 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 Clofazimine Products Have a Food Rule — Ilex Guayusa Should Not Break It

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

2 DOSAGE AND ADMINISTRATION For dapsone-sensitive lepromatous leprosy, 100 mg (two 50 mg capsules) daily with meals as a part of a combination regimen for at least 2 years is recommended.

From the Dosage and Administration section of the FDA label we read for Clofazimine — 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 Clofazimine

This page covers Ilex Guayusa only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Clofazimine page lists 64 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Alfalfa (moderate), Angelica Archangelica (moderate), Arrach (moderate) and Bacillus Coagulans (moderate).

By severity: 1 major · 52 moderate · 11 minor.

From our pharmacist’s overview on the Clofazimine page

“Clofazimine (Lamprene) treats leprosy for months or years, so anything that quietly drains its blood levels deserves genuine caution. Activated charcoal is the single major-rated interaction among the 64 on file, binding the drug and cutting how much reaches your body.”

Reviewed by 2 · Jul 18, 2026

Open the Clofazimine interaction page

How much people look this up

Where Ilex Guayusa and Clofazimine 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

#1,109 of 1,452 supplements looked up here in the last 7 days

29 days ago today

Medication Clofazimine

Top half

#1,254 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 20, 2026. The Ilex Guayusa and Clofazimine 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 Clofazimine

What Is Clofazimine Used For?

Brand name: Lamprene

Lamprene (clofazimine) is used to treat lepromatous leprosy — the most severe form of leprosy (also known as Hansen's disease). This includes cases where the bacteria have become resistant to the antibiotic dapsone, and cases complicated by erythema nodosum leprosum (ENL), a painful inflammatory reaction that can develop during leprosy.

Lamprene must always be used as part of a combination regimen with other anti-leprosy drugs for initial treatment — it should never be used alone at the start of therapy, to prevent the bacteria from becoming resistant to it.

Most-Reported Side Effects for Clofazimine

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Electrocardiogram qt prolonged 762 reports

Nausea 563 reports

Vomiting 503 reports

Anemia 474 reports

Dyspnea 403 reports

See full Clofazimine 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 Clofazimine, 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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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
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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
Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40. PubMed
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
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
Boozer CN, Nasser JA, Heymsfield SB, et al. An herbal supplement containing Ma Huang-Guarana for weight loss: a randomized, double-blind trial. Int J Obes Relat Metab Disord 2001;25:316-24. PubMed
Hagg S, Spigset O, Mjorndal T, Dahlqvist R. Effect of caffeine on clozapine pharmacokinetics in healthy volunteers. Br J Clin Pharmacol 2000;49:59-63. PubMed
Lloyd T, Johnson-Rollings N, Eggli DF, et al. Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation. J Am Coll Nutr 2000;19:256-61. PubMed
Sinclair CJ, Geiger JD. Caffeine use in sports. A pharmacological review. J Sports Med Phys Fitness 2000;40:71-9.
Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. N Engl J Med 2000;343:1833-8. PubMed
Ali M, Afzal M. A potent inhibitor of thrombin stimulated platelet thromboxane formation from unprocessed tea. Prostaglandins Leukot Med 1987;27:9-13. PubMed
Ardlie NG, Glew G, Schultz BG, Schwartz CJ. Inhibition and reversal of platelet aggregation by methyl xanthines. Thromb Diath Haemorrh 1967;18:670-3. DOI
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Klag MJ, Wang NY, Meoni LA, et al. Coffee intake and risk of hypertension: The John Hopkins precursors study. Arch Intern Med 2002;162:657-62. DOI
Ferrini RL, Barrett-Connor E. Caffeine intake and endogenous sex steroid levels in postmenopausal women. The Rancho Bernardo Study. Am J Epidemiol 1996:144:642-4. PubMed
Horner NK, Lampe JW. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness. J Am Diet Assoc 2000;100:1368-80. PubMed
Shekelle PG, Hardy ML, Morton SC, et al. Efficacy and safety of ephedra and ephedrine for weight loss and athletic performance: a meta-analysis. JAMA 2003;289:1537-45.. PubMed
Massey LK. Is caffeine a risk factor for bone loss in the elderly? Am J Clin Nutr 2001;74:569-70. PubMed
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Institute of Medicine. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations. Washington, DC: National Academy Press, 2001. Available at: http://books.nap.edu/books/0309082587/html/index.html. DOI
Dews PB, O'Brien CP, Bergman J. Caffeine: behavioral effects of withdrawal and related issues. Food Chem Toxicol 2002;40:1257-61. PubMed
Beach CA, Mays DC, Guiler RC, et al. Inhibition of elimination of caffeine by disulfiram in normal subjects and recovering alcoholics. Clin Pharmacol Ther 1986;39:265-70. PubMed
Anderson BJ, Gunn TR, Holford NH, Johnson R. Caffeine overdose in a premature infant: clinical course and pharmacokinetics. Anaesth Intensive Care 1999;27:307-11. PubMed
Juliano LM, Griffiths RR. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology (Berl) 2004;176:1-29. PubMed
Winkelmayer WC, Stampfer MJ, Willett WC, Curhan GC. Habitual caffeine intake and the risk of hypertension in women. JAMA 2005;294:2330-5. PubMed
Raaska K, Raitasuo V, Laitila J, Neuvonen PJ. Effect of caffeine-containing versus decaffeinated coffee on serum clozapine concentrations in hospitalised patients. Basic Clin Pharmacol Toxicol 2004;94:13-8. DOI
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Chroscinska-Krawczyk, M., Jargiello-Baszak, M., Walek, M., Tylus, B., and Czuczwar, S. J. Caffeine and the anticonvulsant potency of antiepileptic drugs: experimental and clinical data. Pharmacol.Rep. 2011;63(1):12-18. PubMed
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Mays, D. C., Camisa, C., Cheney, P., Pacula, C. M., Nawoot, S., and Gerber, N. Methoxsalen is a potent inhibitor of the metabolism of caffeine in humans. Clin.Pharmacol.Ther. 1987;42(6):621-626. PubMed
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Norager, C. B., Jensen, M. B., Weimann, A., and Madsen, M. R. Metabolic effects of caffeine ingestion and physical work in 75-year old citizens. A randomized, double-blind, placebo-controlled, cross-over study. Clin Endocrinol (Oxf) 2006;65(2):223-228. PubMed
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Smits P, Straatman C, Pijpers E, Thien T. Dose-dependent inhibition of the hemodynamic response to dipyridamole by caffeine. Clin Pharmacol Ther 1991;50:529-37. PubMed
Zelenitsky SA, Norman A, Nix DE. The effects of fluconazole on the pharmacokinetics of caffeine in young and elderly subjects. J Infect Dis Pharmacother 1995;1:1-11.
Joeres R, Richter E. Mexiletine and caffeine elimination. N Engl J Med 1987;317:117. PubMed
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MacKenzie, T., Comi, R., Sluss, P., Keisari, R., Manwar, S., Kim, J., Larson, R., and Baron, J. A. Metabolic and hormonal effects of caffeine: randomized, double-blind, placebo-controlled crossover trial. Metabolism 2007;56(12):1694-1698. PubMed
Moisey, L. L., Robinson, L. E., and Graham, T. E. Consumption of caffeinated coffee and a high carbohydrate meal affects postprandial metabolism of a subsequent oral glucose tolerance test in young, healthy males. Br.J Nutr. 2010;103(6):833-841. PubMed
Chroscinska-Krawczyk, M., Ratnaraj, N., Patsalos, P. N., and Czuczwar, S. J. Effect of caffeine on the anticonvulsant effects of oxcarbazepine, lamotrigine and tiagabine in a mouse model of generalized tonic-clonic seizures. Pharmacol Rep. 2009;61(5):819 PubMed
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Buscemi, S., Verga, S., Batsis, J. A., Donatelli, M., Tranchina, M. R., Belmonte, S., Mattina, A., Re, A., and Cerasola, G. Acute effects of coffee on endothelial function in healthy subjects. Eur.J Clin Nutr. 2010;64(5):483-489. PubMed
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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.

Related: nutrient depletion

Clofazimine Is Linked to Lower Levels of 7 Nutrients

Natural Medicines records Clofazimine as a medicine that can lower these. This is not an interaction with Ilex Guayusa — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:

Read the full Clofazimine nutrient depletion report ›

Depletion records come from the licensed Natural Medicines database. Do not start a supplement on the strength of this page — ask your pharmacist or doctor whether it applies to you.

Pharmacist Counseling Corner

Taking Ilex Guayusa and Clofazimine Together: Common Questions

Is it safe to take Ilex Guayusa with Clofazimine?

We do not list a known interaction between Ilex Guayusa and Clofazimine. 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 Clofazimine have any of the same side effects?

Yes — our sources link each of them separately to 5 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 Clofazimine at the same time of day?

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

How was the Ilex Guayusa and Clofazimine combination checked?

Interactions in our licensed database are recorded against drug classes. Clofazimine is filed under 3 classifications, and Ilex Guayusa has documented interactions with 37 drug classes — none of Clofazimine'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 — Clofazimine 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 Clofazimine interact with any supplements?

Yes. Clofazimine has documented interactions with 64 supplements in our database — Ilex Guayusa is not one of them. The Clofazimine interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Ilex Guayusa monograph Uses, safety profile, and every drug interaction in one place Clofazimine drug information The full plain-English guide to this medication Clofazimine supplement interactions Every supplement checked against Clofazimine, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 90 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

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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.