Interactions on record — worth a quick check against your medications. Based on 3 of 6 ingredients. Check your meds →
Dietary supplement

Isopure Aminos Cranberry Grape Ingredients & Drug Interactions

by Nature's Best

Isopure Aminos Cranberry Grape label
See full label image
Powder Category: Other Combinations
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 Isopure Aminos Cranberry Grape 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

Isopure Aminos Cranberry Grape is a dietary supplement by Nature's Best with 6 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 709 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Theanine, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Isopure Aminos Cranberry Grape by Nature's Best

Ask about any prescription or over-the-counter medication and we check it for interactions with Isopure Aminos Cranberry Grape by Nature's Best — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Isopure Aminos Cranberry Grape by Nature's Best

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 Aug 6, 2026

What’s inside

Partial disclosure
Ingredient Transparency · database check
Partial

Most active ingredients list an amount, but at least one is hidden in a blend or missing.

Why this rating?
  • The label discloses an exact amount for 3 of its 6 active ingredients.
  • “BCAA Blast Ethyl Ester Recovery Complex” is a proprietary blend — the label gives one combined amount (5 Gram(s)) without saying how much of each component you get.

This powder contains six active ingredients. Three are branched-chain amino acids — L-leucine, L-isoleucine, and L-valine — which are building blocks your body uses for muscle recovery.

You also get vitamin C (an antioxidant and immune supporter), L-theanine (an amino acid linked to relaxation and focus), a blend of branched-chain amino acids called the BCAA Blast Ethyl Ester Recovery Complex, and tart cherry extract (from the sour cherry fruit). The inactive ingredients are flavor, acids, anti-caking agents, sweetener, and food coloring.

Does it work?

Moderate evidence
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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: head to toe recovery post-exercise.
  • We looked for evidence on: Exercise-induced muscle soreness, Exercise-induced muscle damage, Athletic performance, Anxiety, Cognitive function, soreness relief — and 2 related terms.
  • The strongest evidence on file: Sour Cherry is rated "Possibly Effective" for Athletic performance (Natural Medicines).
  • Also on file: Theanine is rated "Possibly Effective" for Cognitive function.
  • Also on file: Sour Cherry is rated "Insufficient Reliable Evidence To Rate" for Cognitive function, Exercise-induced muscle soreness.

Vitamin C is effective for preventing or treating vitamin C deficiency, and possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-related respiratory infections — though the strength of evidence varies. L-theanine is possibly effective for cognitive function; the evidence is insufficient to rate it for age-related cognitive decline, Alzheimer disease, anxiety, or OCD.

Tart cherry extract is possibly effective for athletic performance and exercise-induced muscle soreness, but evidence is insufficient for ADHD, cognitive function, exercise-related infections, or fibromyalgia. The branched-chain amino acids (the three individual ones and the blend) have no effectiveness ratings in our data.

The evidence, ingredient by ingredient Vitamin C Theanine Sour Cherry

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin C is generally well tolerated at normal dietary and supplement doses, though very high doses can cause stomach upset, heartburn, nausea, diarrhea, and headache — especially above 2 grams daily. High-dose infusions carry rare risks of kidney problems.

Normal amounts from food and prenatal vitamins are considered safe, but avoid high-dose supplements unless your doctor advises it. L-theanine is generally well tolerated in healthy adults for short-term use, but long-term safety isn't well studied; it may cause headaches, drowsiness, or increased dreaming.

Tart cherry as whole fruit or juice is generally well tolerated, though concentrated supplements are less studied; some people report stomach pain or loose stools, and rarely a skin reaction possibly due to cherry allergy.

Side effects, ingredient by ingredient Vitamin C Theanine Sour Cherry

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?
  • 2 of the 3 matched ingredients can interact with medications — Vitamin C, Theanine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments.
  • For scale: 709 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 taking this product, check with your doctor or pharmacist if you take warfarin (a blood thinner) — vitamin C in high doses may reduce how well it works. Also double-check if you're on birth control pills or hormone therapy, chemotherapy (especially alkylating agents or antitumor antibiotics), levothyroxine (thyroid medication), HIV drugs like indinavir, the antipsychotic fluphenazine, blood pressure medications, or aluminum-containing products — vitamin C and theanine both have documented interactions with these drug types.

No interactions are documented for the three branched-chain amino acids we checked.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glancePartially disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product is designed for muscle recovery and amino acid support after exercise. If you take warfarin, birth control pills, hormone therapy, chemotherapy, levothyroxine, or blood pressure medications, you need to check with your own doctor or pharmacist before starting this product because of vitamin C's interactions.

Avoid high-dose vitamin C supplements during pregnancy; talk it over with your doctor or pharmacist if you're expecting or breastfeeding, since L-theanine safety data is limited during those times.

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

Assessment coverage: 3 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 22, 2016.

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 Isopure Aminos Cranberry Grape, straight from the product label.

Brand Nature's Best
Barcode (UPC) 089094023430
Net contents 10.05 oz.; 285 Gram(s)
Market status On market
Date entered into DSLD Apr 22, 2016
DSLD ID 58819
Product type Other Combinations
Supplement form Powder
Dietary claims / uses Nutrient, 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 Isopure Aminos Cranberry Grape by Nature's Best, 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:
9.5 Gram(s)
Maximum serving Sizes:
9.5 Gram(s)
Servings per container
30
UPC/BARCODE
089094023430
IngredientAmount% DV
Calories10 {Calories}--
Total Carbohydrates2 Gram(s)1%
L-Leucine0 NP--
L-Isoleucine0 NP--
L-Valine0 NP--
Vitamin C30 mg50%
L-Theanine100 mg--
BCAA Blast Ethyl Ester Recovery Complex5 Gram(s)--
Tart Cherry Extract700 mg--

Other ingredients: Natural and Artificial flavor, Citric Acid, Malic Acid, Tartaric Acid, Silicon Dioxide, Calcium Silicate, Soy Lecithin, Sucralose, FD&C Red 40, FD&C Blue 2

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.
Formula

5 GRAMS BCAA’S PER SERVING 700 MG TART CHERRY PER SERVING 100 MG L-THEANINE PER SERVING ANTIOXIDANT VITAMIN C 10 CALORIES PER SERVING

Proven BCAA’S meet the new-to-the-world combination of Tart Cherry, an anti-inflammatory that helps reduce soreness following intense exercise, and L-Theanine for a calm, relaxed mind. Together they help you make the most of your recovery and hit it harder the next day. Packed with antioxidant Vitamin C, we’ve crafted a lean amino acid powder unlike any other – and the only from Isopure – so you can make more of your muscles.

BCAA’S, TART CHERRY EXTRACT & L-THEANINE FOR HEAD TO TOE RECOVERY

Contains Soy.

Brand IP Statement(s)

HEAD TO TOE RECOVERY

CherryPURE is a registered trademark of Shoreline Fruit, LLC

General Statements

INSTANTIZED WE’RE ALL MORE THAN MUSCLE NOT ALL AMINO ACIDS ARE CREATED EQUAL Introducing a forward-thinking formula to support comprehensive body and mind benefits.

NATURALLY & ARTIFICIALLY FLAVORED

Contents sold by weight, not volume.

Made in the USA-This product contains ingredients of international and domestic origin.

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.

Seals/Symbols

CherryPURE

General

V.1.343.0615US 6033361

FDA Statement of Identity

AMINO SUPPLEMENT

Precautions

Contains Soy.

Warning: Consult your physician before using this product if you are taking any medications or are under a physician’s care for a medical condition. Not for use by those under the age of 18, or women that are pregnant, trying to get pregnant, or nursing.

Not for use by those under the age of 18, or women that are pregnant, trying to get pregnant, or nursing.

Storage

Keep in a cool, dry place.

Suggested/Recommended/Usage/Directions

Directions : Mix one scoop with 10-12 fl oz of water in a shaker or blender. If a shaker or a blender is not convenient, ISOPURE AMINOS can be stirred into solution with a spoon. Take 2 servings per day in addition to your ISOPURE protein drink. Optimal timing is post-workout and bedtime.

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

See for yourself

Isopure Aminos Cranberry Grape by Nature's Best label

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

Isopure Aminos Cranberry Grape 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 Isopure Aminos Cranberry Grape by Nature's Best

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size9.5 Gram(s) Dosage formPowder Servings per container30 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Vitamin C

Interacts with
207 drugs
30 mg per serving Form: Ascorbic Acid

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

L-Theanine

Interacts with
565 drugs
100 mg per serving

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong dro...

L-Theanine monograph & interactions

BCAA Blast Ethyl Ester Recovery Complex

5 Gram(s) per serving
  • › L-Leucine
  • › L-Isoleucine
  • › L-Valine

Tart Cherry Extract

No known
interactions
700 mg per serving Form: Montmorency Tart Cherries

Sour cherry (often sold as tart cherry or Montmorency cherry) is a fruit-based supplement rich in antioxidants that people use for muscle recovery, jo...

Tart Cherry Extract monograph & interactions

Other (inactive) ingredients: Natural and Artificial flavor, Citric Acid, Malic Acid, Tartaric Acid, Silicon Dioxide, Calcium Silicate, Soy Lecithin, Sucralose, FD&C Red 40, FD&C Blue 2. These complete the product’s ingredient list but are not active constituents.

Interaction report

Isopure Aminos Cranberry Grape by Nature's Best Drug Interactions

Want to check YOUR meds against Isopure Aminos Cranberry Grape?

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
709Drugs
273 Moderate 436 Minor

Ingredients driving the most interactions

L-Theanine 565
Vitamin C 207

Individual Drug Interactions

The ingredients in Isopure Aminos Cranberry Grape interact with 709 drugs. Click any drug to see the details.

2 of the 6 ingredients in Isopure Aminos Cranberry Grape interact with drugs. Each result below shows which ingredient is responsible. L-Theanine Vitamin C

Each ingredient & the kinds of drugs it affects

For each ingredient in Isopure Aminos Cranberry Grape with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

L-Theanine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
L-Theanine full monograph & interactions

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Isopure Aminos Cranberry Grape, from the product label.

Nature's Best

See all Nature's Best products
Name
Nature's Best, Inc.
Street Address
195 Engineers Road
City
Hauppauge
State
NY
ZipCode
11788
Web Address
theisopurecompany.com
Pharmacist Counseling Corner

Isopure Aminos Cranberry Grape by Nature's Best: Common Questions

Does Isopure Aminos Cranberry Grape by Nature's Best interact with any medications?
Yes. Based on its ingredients, Isopure Aminos Cranberry Grape has a known interaction with 709 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Isopure Aminos Cranberry Grape contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is 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.
Is this safe if I'm pregnant or breastfeeding?
Vitamin C at normal dietary levels is considered safe during pregnancy and breastfeeding, but avoid high-dose supplements without your doctor's approval. L-theanine safety data is limited, so it's best to avoid it and this product while pregnant or breastfeeding unless your doctor advises otherwise. Talk it over with your doctor or pharmacist for personalized guidance.
What side effects might I notice?
Vitamin C at high doses may cause stomach cramps, heartburn, nausea, or diarrhea — especially above 2 grams daily. L-theanine may cause headaches or drowsiness. Tart cherry extract may cause stomach pain or loose stools in some people. Most users tolerate normal doses without problems.
Does this really help with muscle recovery?
The product contains branched-chain amino acids (leucine, isoleucine, valine) and tart cherry extract, which is possibly effective for exercise-induced muscle soreness. We don't have effectiveness ratings for the branched-chain amino acids themselves in our data, so their role isn't established in the evidence we hold.
Is there any vitamin C in this, and how much?
Yes, vitamin C is one of the active ingredients, but the product facts don't specify the dose per serving. Check the nutrition label or contact the manufacturer for the exact amount so you can track your daily intake, especially if you take other medications.
What is L-theanine and why is it in here?
L-theanine is an amino acid found naturally in tea. It's possibly effective for cognitive function and is included here likely to support mental focus and recovery, though evidence is mixed. It's generally well tolerated but may cause drowsiness in some people.
Can I use this if I take blood pressure medication?
L-theanine may lower blood pressure, so combining it with your blood pressure medication could lower your pressure too much. Check with your own doctor or pharmacist before starting this product to make sure it's safe with your specific medication.

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

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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.

Isopure Aminos Cranberry Grape label
Go deeper

The Full Monographs Behind Isopure Aminos Cranberry Grape’s Ingredients

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

Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Theanine

Interacts with 565 drugs

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong drowsiness. Early research suggests it may...

Read the full Theanine monograph → Herb & supplement monograph

Sour Cherry

Sour cherry (often sold as tart cherry or Montmorency cherry) is a fruit-based supplement rich in antioxidants that people use for muscle recovery, joint and gout symptoms, and sleep. Early...

Read the full Sour Cherry monograph →
Sources

Sources & How We Checked

Isopure Aminos Cranberry Grape'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 61 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.

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
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See these in context on the Theanine monograph →

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See these in context on the Sour Cherry 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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