Drug & supplement interaction

Green Coffee + Phendimetrazine

Phendimetrazine brand names: Plegine, Metra, Weightrol.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 13, 2026

The bottom line No known interaction

We found no known interaction between Green Coffee and Phendimetrazine 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 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

Green Coffee and Phendimetrazine

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 Phendimetrazine and Green Coffee 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.

Green Coffee safety at a glance

Green Coffee overall Use caution Generally well tolerated in food amounts, but supplements contain caffeine and may cause stimulant-related effects.

Pregnancy Use caution Limit caffeine during pregnancy; concentrated supplement amounts are not well studied, so it is best to avoid them.

Breastfeeding Use caution Caffeine passes into breast milk; avoid concentrated supplements and limit intake.

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

Still wondering about combining Phendimetrazine and Green Coffee? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

How we checked

Why No Interaction Is Listed for Phendimetrazine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Phendimetrazine is filed under a single classification — oral drugs. Green Coffee has documented interactions with 31 drug classes — the most serious being ephedrine (major), adenosine (adenocard) (moderate) and alendronate (fosamax) (moderate) — and none of Phendimetrazine’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

Green Coffee Does Interact With Other Medications

Green Coffee has 8 major, 442 moderate, 222 minor known drug interactions in our database — Phendimetrazine isn’t one of them. If you take anything else, check it against the full list below.

Major 8 Moderate 442 Minor 222 No known interaction 2,158 (incl. Phendimetrazine)

Taking anything else?

Check Another of Your Medications Against Green Coffee

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

What to actually watch for

No Interaction Found — But Data Suggests Green Coffee and Phendimetrazine 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.

Raised blood pressure Worth acting on Additional detail
Green Coffee
“Although acute administration of caffeine, a constituent of green coffee, can cause increased blood pressure, regular consumption does not seem to increase either blood pressure or pulse, even in mildly hypertensive patients.”

Green Coffee · Natural Medicines adverse-effect record, reported in hypertension.
6 sources cited

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

8033. 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

8035. Olthof MR, Hollman PC, Zock PL, Katan MB. Consumption of high doses of chlorogenic acid, present in coffee, or of black tea increases plasma total homocysteine concentrations in humans. Am J Clin Nutr 2001;73:532-8. PubMed
Phendimetrazine

Listed in the ADVERSE REACTIONS section of the FDA label for Phendimetrazine. Read the label on DailyMed ›
Anxiety or restlessness / Headache Additional detail
Green Coffee
“Chronic use of caffeine, especially in large amounts, may produce tolerance, habituation, and psychological dependence. Abrupt discontinuation of caffeine may result in physical withdrawal symptoms, including headache, fatigue, drowsiness, decreased physical energy, difficulty concentrating, depression, anxiety, irritability, and reduced alertness.”

Green Coffee · Natural Medicines adverse-effect record, reported in anxiety.
3 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

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
Phendimetrazine

Listed in the ADVERSE REACTIONS section of the FDA label for Phendimetrazine. Read the label on DailyMed ›
Dizziness Additional detail
Green Coffee
“Orally, dizziness was reported by one person in a clinical trial of green coffee extract.”

Green Coffee · Natural Medicines adverse-effect record, reported in vertigo.
1 source cited

104831. Roshan H, Nikpayam O, Sedaghat M, Sohrab G. Effects of green coffee extract supplementation on anthropometric indices, glycaemic control, blood pressure, lipid profile, insulin resistance and appetite in patients with the metabolic syndrome: a randomised
Phendimetrazine

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

Reported for Green Coffee but not commonly for Phendimetrazine: trouble concentrating, dependence or withdrawal symptoms, mood changes or irritability and bone thinning.

Effects for Phendimetrazine come from the ADVERSE REACTIONS section of its FDA label; effects for Green Coffee 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.

Overlapping uses

What Phendimetrazine Is Prescribed For, and What Green Coffee Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Phendimetrazine is a prescription medicine with approved uses on its FDA label. Green Coffee is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Phendimetrazine is prescribed for: Phendimetrazine tartrate is used to help manage exogenous obesity (excess body weight from outside causes like diet and lifestyle) as a short-term addition to a calorie-restricted diet. It is intended for adults with a BMI of 30 or higher, or a BMI of 27 or higher when other risk factors — such as high blood pressure, diabetes, or high cholesterol — are also present. It is approved for use as monotherapy only, meaning it must not be combined with other weight-loss drugs or stimulants. Both the tablet form and the extended-release capsule form are approved for this purpose.

Read the rest of what Phendimetrazine is prescribed for

This medication is meant to be used for only a few weeks as part of a broader weight-management plan.

Green Coffee has been studied for:

Diabetes studied, not established Green Coffee has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

Green Coffee for diabetes

Although there has been interest in using oral green coffee for diabetes, there is insufficient reliable information about the clinical effects of green coffee for this condition.
Obesity studied, not established Green Coffee has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

Green Coffee for obesity

Oral green coffee extract may have a small effect on weight loss.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Phendimetrazine on your own; if you are taking Green Coffee for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

Everything else you take

See Every Supplement That Interacts With Phendimetrazine

This page covers Green Coffee only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phendimetrazine page lists 17 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 7 moderate · 9 minor.

From our pharmacist’s overview on the Phendimetrazine page

“Of the 17 supplements on file for phendimetrazine, an appetite-suppressant stimulant prescribed short term for weight loss, activated charcoal is the one that demands real caution. Charcoal binds medications in the gut and can sharply cut how much of a drug your body absorbs, leaving you with less appetite control than your prescriptio…”

Reviewed by 2 · Jul 18, 2026

Open the Phendimetrazine interaction page

One more smart check

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

We hold 1,716 real supplement products containing Green Coffee, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Green Coffee. Even though Green Coffee itself has no known interaction with Phendimetrazine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Green Coffee and Phendimetrazine 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 Green Coffee

Top half

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

29 days ago today

Medication Phendimetrazine

Top 25%

#345 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 Green Coffee reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Green Coffee and Phendimetrazine 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 Green Coffee

What is Green Coffee?

Weight loss
High blood pressure
Blood sugar control
Antioxidant support
General energy

Green coffee is the unroasted bean of the coffee plant, prized for its high chlorogenic acid content. Some early studies suggest modest benefits for weight, blood pressure, and blood sugar, but the evidence is limited and far from conclusive. It contains caffeine, so people sensitive to stimulants should use caution and check with a pharmacist or doctor first.

Coffea arabica · Rubiaceae · Raw (unroasted) coffee beans (seeds) · Capsules, tablets, powders, extracts, and brewed beverages

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

Green Coffee: dosing

There is no official, standardized dose for green coffee. Products vary widely in how much chlorogenic acid and caffeine they contain, which makes comparing them difficult.The best approach is to follow the directions on the product label and not exceed the recommended amount. Because green coffee contains caffeine, count it toward your total daily caffeine intake from all sources.

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

Read the full Green Coffee monograph & all interactions

Medication

About Phendimetrazine

What Is Phendimetrazine Used For?

Brand names: Plegine, Metra, Weightrol

Phendimetrazine tartrate is used to help manage exogenous obesity (excess body weight from outside causes like diet and lifestyle) as a short-term addition to a calorie-restricted diet. It is intended for adults with a BMI of 30 or higher, or a BMI of 27 or higher when other risk factors — such as high blood pressure, diabetes, or high cholesterol — are also present.

It is approved for use as monotherapy only, meaning it must not be combined with other weight-loss drugs or stimulants. Both the tablet form and the extended-release capsule form are approved for this purpose. This medication is meant to be used for only a few weeks as part of a broader weight-management plan.

See full Phendimetrazine drug information

Keep checking

Other Drugs & Green Coffee

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

8Major

442Moderate

222Minor

2,157No known interaction

8 Major 442 Moderate 222 Minor 2,157 No interaction

Major

8 interactions

Moderate

442 interactions

Showing 60 of 442 moderate interactions — see all 442 on the Green Coffee page.

Minor

222 interactions

Showing 60 of 222 minor interactions — see all 222 on the Green Coffee page.

No interaction 2,157 drugs checked — show the list

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

Showing the 60 most looked-up of 2,157 medications checked with no known interaction — see the full Green Coffee list.

See the full Green Coffee interactions page

See every supplement checked against Phendimetrazine, ranked by severity

Evidence & sources

Green Coffee References

The 103 references that drive our Green Coffee 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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Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
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
Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
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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
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
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
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
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
Samarrae WA, Truswell AS. Short-term effect of coffee on blood fibrinolytic activity in healthy adults. Atherosclerosis 1977;26:255-60. PubMed
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
Olthof MR, Hollman PC, Zock PL, Katan MB. Consumption of high doses of chlorogenic acid, present in coffee, or of black tea increases plasma total homocysteine concentrations in humans. Am J Clin Nutr 2001;73:532-8. PubMed
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
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
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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Aqel RA, Zoghbi GJ, Trimm JR, et al. Effect of caffeine administered intravenously on intracoronary-administered adenosine-induced coronary hemodynamics in patients with coronary artery disease. Am J Cardiol 2004;93:343-6. PubMed
Zheng XM, Williams RC. Serum caffeine levels after 24-hour abstention: clinical implications on dipyridamole (201)Tl myocardial perfusion imaging. J Nucl Med Technol 2002;30:123-7.
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
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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
Forrest WH Jr, Bellville JW, Brown BW Jr. The interaction of caffeine with pentobarbital as a nighttime hypnotic. Anesthesiology 1972;36:37-41. PubMed
Lake CR, Rosenberg DB, Gallant S, et al. Phenylpropanolamine increases plasma caffeine levels. Clin Pharmacol Ther 1990;47:675-85. PubMed
Ochiai R, Jokura H, Suzuki A, et al. Green coffee bean extract improves human vasoreactivity. Hypertens Res 2004;27:731-7. PubMed
Kozuma K, Tsuchiya S, Kohori J, et al. Antihypertensive effect of green coffee bean extract on mildly hypertensive subjects. Hypertens Res. 2005 Sep;28(9):711-8. PubMed
Watanabe T, Arai Y, Mitsui Y, et al. The blood pressure-lowering effect and safety of chlorogenic acid from green coffee bean extract in essential hypertension. Clin Exp Hypertens 2006;28:439-49. PubMed
Thom E. The effect of chlorogenic acid enriched coffee on glucose absorption in healthy volunteers and its effect on body mass when used long-term in overweight and obese people. J Int Med Res 2007;35:900-8. PubMed
Blum J, Lemaire B, and Lafay S. Effect of a green decaffeinated coffee extract on glycaemia: a pilot prospective study. Nutrafoods 2007;6(3):13-17.
Thong FS and Graham TE. Caffeine-induced impairment of glucose tolerance is abolished by beta-adrenergic receptor blockade in humans. J Appl Physiol (1985). 2002 Jun;92:2347-52.
Greer F, Hudson R, Ross R, et al. Caffeine ingestion decreases glucose disposal during a hyperinsulinemic-euglycemic clamp in sedentary humans. Diabetes. 2001 Oct;50:2349-54. PubMed
Keijzers GB, De Galan BE, Tack CJ, et al. Caffeine can decrease insulin sensitivity in humans. Diabetes Care. 2002 Feb;25:364-9. PubMed
Johnston KL, Clifford MN, Morgan LM. Coffee acutely modifies gastrointestinal hormone secretion and glucose tolerance in humans: glycemic effects of chlorogenic acid and caffeine. Am J Clin Nutr. 2003 Oct;78:728-33. PubMed
van Rooij J, van der Stegen GH, Schoemaker RC, et al. A placebo-controlled parallel study of the effect of two types of coffee oil on serum lipids and transaminases: identification of chemical substances involved in the cholesterol-raising effect of coffe
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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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Zhang LL, Zhang JR, Guo K, et al. Effects of fluoroquinolones on CYP4501A and 3A in male broilers. Res Vet Sci 2011;90:99-105. PubMed
Cesana M, Broccali G, Imbimbo BP, Crema A. Effect of single doses of rufloxacin on the disposition of theophylline and caffeine after single administration. Int J Clin Pharmacol Ther Toxicol 1991:29:133-8.
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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
Smits, P., Temme, L., and Thien, T. The cardiovascular interaction between caffeine and nicotine in humans. Clin Pharmacol Ther 1993;54(2):194-204. PubMed
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
Simmonds, M. J., Minahan, C. L., and Sabapathy, S. Caffeine improves supramaximal cycling but not the rate of anaerobic energy release. Eur.J Appl Physiol 2010;109(2):287-295. PubMed
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.

Pharmacist Counseling Corner

Taking Green Coffee and Phendimetrazine Together: Common Questions

Is it safe to take Green Coffee with Phendimetrazine?

We do not list a known interaction between Green Coffee and Phendimetrazine. 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 Green Coffee and Phendimetrazine have any of the same side effects?

Yes — our sources link each of them separately to 4 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.

Are Green Coffee and Phendimetrazine used for the same thing?

They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Green Coffee in each. That is a conversation for your prescriber, especially if Phendimetrazine is being adjusted to a target.

How was the Green Coffee and Phendimetrazine combination checked?

Interactions in our licensed database are recorded against drug classes. Phendimetrazine is filed under 1 classification, and Green Coffee has documented interactions with 31 drug classes — none of Phendimetrazine'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 Green Coffee interact with any other medications?

Yes. Green Coffee has 672 documented drug interactions in our database — Phendimetrazine 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 Phendimetrazine interact with any supplements?

Yes. Phendimetrazine has documented interactions with 17 supplements in our database — Green Coffee is not one of them. The Phendimetrazine 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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Green Coffee monograph Uses, safety profile, and every drug interaction in one place Phendimetrazine drug information The full plain-English guide to this medication Phendimetrazine supplement interactions Every supplement checked against Phendimetrazine, 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 103 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.