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Dietary supplement

RK Maxx Five Hundred Ingredients & Drug Interactions

by EFL Nutritionals

RK Maxx Five Hundred label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking RK Maxx Five Hundred against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

RK Maxx Five Hundred is a dietary supplement by EFL Nutritionals with 1 active ingredient. Its ingredients are commonly taken for weight loss, fat burning, boosting metabolism.Based on those ingredients, 174 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Raspberry Ketone. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against RK Maxx Five Hundred by EFL Nutritionals

Ask about any prescription or over-the-counter medication and we check it for interactions with RK Maxx Five Hundred by EFL Nutritionals — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of RK Maxx Five Hundred by EFL Nutritionals

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Sep 10, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

RK Maxx Five Hundred contains one active ingredient: raspberry ketone. The capsule also holds vegetable cellulose as an inactive filler.

Raspberry ketone is a naturally occurring compound isolated from red raspberries. It's been studied for potential effects on hair loss (alopecia areata) and weight management, though the evidence remains limited.

Does it work?

Not established
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use — see Raspberry Ketone's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: weight loss and fat burning support.
  • We looked for evidence on: Obesity, metabolic support, appetite control.
  • The closest evidence on file: Raspberry Ketone is rated "Insufficient Reliable Evidence To Rate" for Obesity (Natural Medicines).

The data we hold shows insufficient reliable evidence to rate raspberry ketone for alopecia areata (hair loss) or obesity. While it has been studied for both uses, the current research doesn't support a clear claim that it works for either condition.

If you're considering this product for one of those purposes, talk it over with your doctor or pharmacist about what the evidence actually shows.

The evidence, ingredient by ingredient Raspberry Ketone

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Raspberry ketone is used safely in foods, but safety data for the high doses in supplements is very limited in humans. Because of its structural similarity to stimulants, cases of heart palpitations, elevated blood pressure, tachycardia (fast heartbeat), and even dangerous irregular heartbeats have been reported.

A small number of people have also reported sweating, diarrhea, and shakiness after taking it. There isn't enough safety information to use this product during pregnancy or while breastfeeding.

If you're pregnant or nursing, talk with your doctor or pharmacist before taking it.

Side effects, ingredient by ingredient Raspberry Ketone

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Raspberry Ketone.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 174 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you start RK Maxx Five Hundred, check with your doctor or pharmacist if you take any stimulant medications (prescription or over-the-counter) or warfarin. The moderate-severity risks with stimulants include heart palpitations and dangerous irregular heartbeats, and warfarin may lose effectiveness and require a dose adjustment while you're taking this product.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

RK Maxx Five Hundred is worth considering only if you're interested in raspberry ketone for hair loss or weight management — though the evidence for either is weak. Don't use it if you take stimulant drugs or warfarin without checking with your doctor or pharmacist first.

Run your exact medications through the interaction checker on this page, and talk with your healthcare provider about whether it makes sense for you.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Dec 29, 2014.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about RK Maxx Five Hundred, straight from the product label.

Brand EFL Nutritionals
Barcode (UPC) 628586449831
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Dec 29, 2014
DSLD ID 40668
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for RK Maxx Five Hundred by EFL Nutritionals, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
60
UPC/BARCODE
628586449831
IngredientAmount% DV
Raspberry Ketone500 mg--

Other ingredients: Vegetable Cellulose

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Seals/Symbols

GOOD MANUFACTURING PRACTICE GMP

Made in USA

General Statements

EMPOWERED FOR LIFE

Suggested/Recommended/Usage/Directions

SUGGESTED USE: As a Dietary supplement, take one (1) capsule daily before breakfast with an 8 oz. glass of water.

Precautions

CAUTION: Do not exceed recommended dose.

pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement.

pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement.

KEEP OUT OF REACH OF CHILDREN

DO NOT USE IF SAFETY SEAL IS DAMAGED OR MISSING

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Formula

Raspberry Ketones-500MG

Storage

STORE IN A COOL, DRY PLACE.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

RK Maxx Five Hundred by EFL Nutritionals label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

RK Maxx Five Hundred label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in RK Maxx Five Hundred by EFL Nutritionals

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Raspberry Ketone

Interacts with
174 drugs
500 mg per serving

Raspberry ketone is a natural aroma compound found in red raspberries that is heavily marketed for weight loss, but there is no good human evidence th...

Raspberry Ketone monograph & interactions

Other (inactive) ingredients: Vegetable Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

RK Maxx Five Hundred by EFL Nutritionals Drug Interactions

Want to check YOUR meds against RK Maxx Five Hundred?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
174Drugs
174 Moderate

Ingredients driving the most interactions

Raspberry Ketone 174

Individual Drug Interactions

The ingredients in RK Maxx Five Hundred interact with 174 drugs. Click any drug to see the details.

1 of the 1 ingredient in RK Maxx Five Hundred interact with drugs. Each result below shows which ingredient is responsible. Raspberry Ketone

Each ingredient & the kinds of drugs it affects

For each ingredient in RK Maxx Five Hundred with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Raspberry Ketone2 drug types · 174 drugs

Stimulant Drugs

Theoretically, raspberry ketone might increase the risk of adverse cardiovascular effects with stimulant drugs.
Structurally, raspberry ketone resembles synephrine, a known stimulant agent. Heart palpitations, elevated blood pressure, coronary vasospasm, pulseless electrical activity arrest, and resistant polymorphic ventricular tachycardia have been reported in patients taking raspberry ketone.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, raspberry ketone might increase warfarin dose requirements.
In one case report, a patient taking warfarin 55 mg per week had a decrease in INR over a period of one month while taking raspberry ketone 250 mg daily. A warfarin dose increase to 70 mg per week was necessary to maintain a therapeutic INR while taking raspberry ketone. The mechanism for this potential interaction is not known.

Likelihood Possible Evidence D
Raspberry Ketone full monograph & interactions
The maker

Brand information

Manufacturer and brand details for RK Maxx Five Hundred, from the product label.

EFL Nutritionals

See all EFL Nutritionals products
Name
EFL Nutritionals
Phone Number
405-708-6328
Web Address
www.eflnutritionals.com
Pharmacist Counseling Corner

RK Maxx Five Hundred by EFL Nutritionals: Common Questions

Does RK Maxx Five Hundred by EFL Nutritionals interact with any medications?
Yes. Based on its ingredients, RK Maxx Five Hundred has a known interaction with 174 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
RK Maxx Five Hundred contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What is raspberry ketone supposed to do?
Raspberry ketone has been studied for potential effects on hair loss and weight management. However, the evidence we hold rates it as insufficient to clearly support either use. Talk with your doctor about whether it's a reasonable choice for what you're hoping to address.
Can I take this while I'm pregnant or breastfeeding?
There isn't enough safety information. The data advises against use during pregnancy and while breastfeeding. If you're pregnant or nursing and interested in this product, talk with your doctor or pharmacist for personalized advice.
What are the side effects I should watch for?
Because raspberry ketone resembles a stimulant, heart palpitations, fast heartbeat, elevated blood pressure, and dangerous irregular heartbeats have been reported in cases. A small number of people have also experienced sweating, diarrhea, and shakiness. These aren't well studied overall, but if you notice any of these, stop taking it and contact your doctor.
I take warfarin — can I use this?
No — not without talking to your doctor first. Raspberry ketone may lower warfarin's effectiveness, requiring a dose increase to maintain safe blood thinning. Your doctor will need to monitor your clotting time if you decide to take both.
Is there anything else in this capsule besides raspberry ketone?
The capsule itself is made of vegetable cellulose, an inactive ingredient. Raspberry ketone is the only active ingredient.

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

Not sure if RK Maxx Five Hundred is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

RK Maxx Five Hundred label
Go deeper

The Full Monographs Behind RK Maxx Five Hundred’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Raspberry Ketone

Interacts with 174 drugs

Raspberry ketone is a natural aroma compound found in red raspberries that is heavily marketed for weight loss, but there is no good human evidence that it helps people lose weight. Most cla...

Read the full Raspberry Ketone monograph →
Sources

Sources & How We Checked

RK Maxx Five Hundred's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 4 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Raspberry Ketone 4 references
  1. Adverse Event Report. Raspberry Ketone. Natural MedWatch, April 27, 2012.
  2. Adverse Event Report. Raspberry Ketone. Natural MedWatch, September 18, 2011.
  3. Ansari SA, Patel F, Ashouri D, Dhaliwal JSS, Desai A. Resistant Polymorphic Ventricular Tachycardia in a Patient Taking Raspberry Ketones Weight Loss Supplement. Cureus 2022;14(12):e33089. PubMed
  4. Khattar A, Beeton I. Coronary vasospasm and raspberry ketones weight-loss supplement: Is there a connection? Anatol J Cardiol. 2020;24(3):205-208.

See these in context on the Raspberry Ketone monograph →

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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