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Dietary supplement

Sustained Focus Ingredients & Drug Interactions

by Nature's Way

Sustained Focus label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Sustained Focus 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

Sustained Focus is a dietary supplement by Nature's Way with 2 active ingredients. Its ingredients are commonly taken for anxiety and stress, relaxation and calm, sleep support.Based on those ingredients, 859 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Neumentix, L-Theanine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Sustained Focus by Nature's Way

Ask about any prescription or over-the-counter medication and we check it for interactions with Sustained Focus by Nature's Way — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Sustained Focus by Nature's Way

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 Jul 11, 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 3 of its 3 active ingredients.
  • “Neumentix” is listed as a grouped ingredient — the label gives one combined amount (900 mg) without saying how much of each component you get.

Sustained Focus contains 3 active ingredients. L-theanine is an amino acid that promotes calm focus without drowsiness by boosting a brain chemical called GABA.

The product also includes polyphenols and rosmarinic acid, both plant compounds with antioxidant properties, though we hold no interaction data for either of them. The capsule itself contains inactive ingredients — hypromellose, cellulose, magnesium stearate, and silica — that serve as binders and fillers.

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: Helps stay on task and support concentration.
  • We looked for evidence on: Attention deficit-hyperactivity disorder (ADHD), Cognitive function, Cognitive impairment, Age-related cognitive decline, Mental clarity, Executive function — and 1 related terms.
  • The strongest evidence on file: Theanine is rated "Possibly Effective" for Cognitive function (Natural Medicines).
  • Also on file: Theanine is rated "Insufficient Reliable Evidence To Rate" for Age-related cognitive decline, Attention deficit-hyperactivity disorder (ADHD), Cognitive impairment.

L-theanine is possibly effective for supporting cognitive function, which is what this product is built around. The evidence is less clear for age-related cognitive decline, Alzheimer disease, and anxiety disorders — the data available isn't strong enough to rate those uses.

We hold no effectiveness ratings for polyphenols or rosmarinic acid in the data we have on file.

The evidence, ingredient by ingredient Theanine Spearmint

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.

L-theanine is generally well tolerated in healthy adults for short-term use, but long-term safety hasn't been well studied. Some people report headaches, drowsiness, longer sleep, or more vivid dreams.

One child developed facial tics while taking a high dose, though the tics stopped when she stopped the supplement — and she had a history of tics beforehand, so the link wasn't clear. Not enough safety data exists for pregnancy or breastfeeding.

The facts advise against use during these times. If you're pregnant, nursing, or planning to become pregnant, talk with your doctor or pharmacist before starting this product.

Side effects, ingredient by ingredient Theanine Spearmint

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 — Theanine.
  • The most serious interaction on file is rated Moderate.
  • For scale: 565 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.

Double-check this product if you take blood pressure medications (Moderate interaction with L-theanine), sedating drugs like sleep aids or anxiety medications (Minor interaction), or serotonergic antidepressants (Minor interaction). Use the medication checker on this page to confirm your specific drugs.

Check your own medication Run your meds through the checker above

The bottom line

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

Sustained Focus is worth considering if you're looking to sharpen focus without sedation and you don't take blood pressure medications. If you're on any prescription drugs — especially for blood pressure, sleep, or mood — check them against this product first.

A quick conversation with your pharmacist will confirm it's right for you.

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

Assessment coverage: 1 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 24, 2025.

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 Sustained Focus, straight from the product label.

Brand Nature's Way
Barcode (UPC) 033674136911
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Jul 24, 2025
DSLD ID 333773
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free, Dairy Free
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 Sustained Focus by Nature's Way, 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:
3 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
Servings per container
20
UPC/BARCODE
033674136911
IngredientAmount% DV
Total Carbohydrates1 Gram(s)1%
L-Theanine200 mg--
Polyphenols216 mg--
Rosmarinic Acid130.5 mg--
Neumentix900 mg--

Other ingredients: Hypromellose, Cellulose, Magnesium Stearate, Silica

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.
Formulation

Helps you stay on task Supports concentration Supports cognitive performance

Gluten free. No wheat, corn, soy, dairy, gelatin, or artificial colors or flavors. Vegan Gelatin Free

Vegan Gelatin Free

Bottled and tested in the USA

Caffeine free

Improves focus & concentration

General Statements

Explore more products at NATURESWAY.COM

50% Bottle made from 50% post-consumer recycled plastic

Brand IP Statement(s)

Neumentix is a registered trademark of Kemin Industries, Inc.

Copyright 2024 Nature’s Way Brands, LLC

Formula

Neumentix Phenolic Complex K110-42

Sustained Focus with clinically studied Neumentix Spearmint Extract

L-Theanine helps calm the mind

Seals/Symbols

Vegan Gelatin Free

FDA Disclaimer Statement

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

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Recommendation: Adults take 3 capsules once daily, preferably with food.

Precautions

Do not exceed recommended dose.

Warning: Do not take if you are pregnant or nursing. If you are taking any medications, consult a healthcare professional before use.

Keep out of reach of children.

Safety sealed with inner seal. Do not use if seal is broken or missing.

Storage

Store at room temperature. Avoid excessive heat and direct sunlight.

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

See for yourself

Sustained Focus by Nature's Way label

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

Sustained Focus 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 Sustained Focus by Nature's Way

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size3 Capsule(s) Dosage formCapsule Servings per container20 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.

L-Theanine

Interacts with
565 drugs
200 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

Neumentix

Interacts with
579 drugs
900 mg per serving Form: Spearmint Leaf Extract

Spearmint is a common culinary mint that is generally safe in food and tea amounts. Early research suggests possible benefits for digestion, mild horm...

Neumentix monograph & interactions
  • › Polyphenols
  • › Rosmarinic Acid

Other (inactive) ingredients: Hypromellose, Cellulose, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

Sustained Focus by Nature's Way Drug Interactions

Want to check YOUR meds against Sustained Focus?

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
859Drugs
735 Moderate 124 Minor

Ingredients driving the most interactions

Neumentix 579
L-Theanine 565

Individual Drug Interactions

The ingredients in Sustained Focus interact with 859 drugs. Click any drug to see the details.

2 of the 2 ingredients in Sustained Focus interact with drugs. Each result below shows which ingredient is responsible. Neumentix L-Theanine

Each ingredient & the kinds of drugs it affects

For each ingredient in Sustained Focus 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.

Neumentix2 drug types · 579 drugs

Cns Depressants

Theoretically, spearmint might alter the sedative effects of CNS depressants.
Animal research suggests that (-)-carvone, a major constituent of spearmint, has sedative effects. However, in humans, chewing spearmint-flavored gum induced arousal effects.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, high doses of spearmint might increase the risk of liver damage when taken with hepatotoxic drugs.
Animal research suggests that drinking spearmint tea for 30 days can increase markers of liver damage, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and cause liver degeneration and necrosis, in a dose-dependent manner. This effect has not been reported in humans.

Likelihood Possible Evidence D
Neumentix full monograph & interactions

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
The maker

Brand information

Manufacturer and brand details for Sustained Focus, from the product label.

Nature's Way

See all Nature's Way products
Name
Nature's Way Brands, LLC
City
Green Bay
State
WI
ZipCode
54311
Phone Number
1-800-962-8873
Web Address
naturesway.com
Pharmacist Counseling Corner

Sustained Focus by Nature's Way: Common Questions

Does Sustained Focus by Nature's Way interact with any medications?
Yes. Based on its ingredients, Sustained Focus has a known interaction with 859 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Sustained Focus contains 2 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.
Can I take this while pregnant or breastfeeding?
The safety data isn't there yet to say it's okay. The facts advise against use during pregnancy and breastfeeding. Talk with your doctor or pharmacist — they can help you decide what's best for you and your baby.
What's L-theanine supposed to do?
It's an amino acid that helps you stay calm and focused without making you sleepy. It works by boosting GABA, a brain chemical that promotes relaxation. Studies show it's possibly effective for cognitive function.
What side effects might I notice?
Most people tolerate it well. Some report headaches, drowsiness, longer sleep, or more vivid dreams. These aren't common, but they do happen.
Is this safe to take long-term?
Short-term use in healthy adults is generally well tolerated, but long-term safety hasn't been studied carefully. If you plan to take it for months, mention that to your pharmacist.
Does it really help with focus?
L-theanine is possibly effective for cognitive function based on the evidence we have. If you're looking for a proven sharp-focus boost, the data is stronger for that than for other uses like anxiety or age-related decline.

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

Not sure if Sustained Focus is safe with your meds?

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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.

Sustained Focus label
Go deeper

The Full Monographs Behind Sustained Focus’s Ingredients

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

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

Spearmint

Interacts with 579 drugs

Spearmint is a common culinary mint that is generally safe in food and tea amounts. Early research suggests possible benefits for digestion, mild hormone-related issues (such as excess facia...

Read the full Spearmint monograph →
Sources

Sources & How We Checked

Sustained Focus'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 26 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.

Theanine 6 references
  1. Yokogoshi H, Kobayashi M. Hypotensive effect of gamma-glutamylethylamide in spontaneously hypertensive rats. Life Sci 1998;62:1065-8.
  2. Haskell, C. F., Kennedy, D. O., Milne, A. L., Wesnes, K. A., and Scholey, A. B. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol.Psychol. 2008;77(2):113-122. PubMed
  3. Yokogoshi, H., Kato, Y., Sagesaka, Y. M., Takihara-Matsuura, T., Kakuda, T., and Takeuchi, N. Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci.Biotechnol.Biochem. 1995;59(4):615-618. PubMed
  4. Lyon MR, Kapoor MP, Juneja LR. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. Altern Med Rev. 2011;16(4):348-
  5. Hidese S, Ota M, Wakabayashi C, et al. Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study. Acta Neuropsychiatr 2017;29(2):72-9.
  6. Tsuchiya T, Honda H, Oikawa M, et al. Oral administration of the amino acids cystine and theanine attenuates the adverse events of S-1 adjuvant chemotherapy in gastrointestinal cancer patients. Int J Clin Oncol 2016;21(6):1085-90. PubMed

See these in context on the Theanine monograph →

Spearmint 20 references
  1. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  2. Akdogan M, Ozguner M, Aydin G, Gokalp O. Investigation of biochemical and histopathological effects of Mentha piperita Labiatae and Mentha spicata Labiatae on liver tissue in rats. Hum Exp Toxicol 2004;23:21-8.
  3. Poon, T. S. and Freeman, S. Cheilitis caused by contact allergy to anethole in spearmint flavoured toothpaste. Australas.J Dermatol. 2006;47(4):300-301. PubMed
  4. Andersen, K. E. Contact allergy to toothpaste flavors. Contact Dermatitis 1978;4(4):195-198. PubMed
  5. de Sousa, D. P., Farias Nobrega, F. F., and de Almeida, R. N. Influence of the chirality of (R)-(-)- and (S)-(+)-carvone in the central nervous system: a comparative study. Chirality 5-5-2007;19(4):264-268.
  6. Larsen, W., Nakayama, H., Fischer, T., Elsner, P., Frosch, P., Burrows, D., Jordan, W., Shaw, S., Wilkinson, J., Marks, J., Jr., Sugawara, M., Nethercott, M., and Nethercott, J. Fragrance contact dermatitis: a worldwide multicenter investigation (Part II PubMed
  7. Guney, M., Oral, B., Karahanli, N., Mungan, T., and Akdogan, M. The effect of Mentha spicata Labiatae on uterine tissue in rats. Toxicol.Ind.Health 2006;22(8):343-348.
  8. Masumoto, Y., Morinushi, T., Kawasaki, H., Ogura, T., and Takigawa, M. Effects of three principal constituents in chewing gum on electroencephalographic activity. Psychiatry Clin.Neurosci. 1999;53(1):17-23. PubMed
  9. Bulat, R., Fachnie, E., Chauhan, U., Chen, Y., and Tougas, G. Lack of effect of spearmint on lower oesophageal sphincter function and acid reflux in healthy volunteers. Aliment.Pharmacol Ther. 1999;13(6):805-812. PubMed
  10. Francalanci, S., Sertoli, A., Giorgini, S., Pigatto, P., Santucci, B., and Valsecchi, R. Multicentre study of allergic contact cheilitis from toothpastes. Contact Dermatitis 2000;43(4):216-222. PubMed
  11. Bonamonte, D., Mundo, L., Daddabbo, M., and Foti, C. Allergic contact dermatitis from Mentha spicata (spearmint). Contact Dermatitis 2001;45(5):298.
  12. Tomson, N., Murdoch, S., and Finch, T. M. The dangers of making mint sauce. Contact Dermatitis 2004;51(2):92-93. PubMed
  13. Clayton, R. and Orton, D. Contact allergy to spearmint oil in a patient with oral lichen planus. Contact Dermatitis 2004;51(5-6):314-315. PubMed
  14. Dal Sacco, D., Gibelli, D., and Gallo, R. Contact allergy in the burning mouth syndrome: a retrospective study on 38 patients. Acta Derm.Venereol. 2005;85(1):63-64. PubMed
  15. Goncalves, J. C., Oliveira, Fde S., Benedito, R. B., de Sousa, D. P., de Almeida, R. N., and de Araujo, D. A. Antinociceptive activity of (-)-carvone: evidence of association with decreased peripheral nerve excitability. Biol Pharm Bull. 2008;31(5):1017- PubMed
  16. Ormerod, A. D. and Main, R. A. Sensitisation to "sensitive teeth" toothpaste. Contact Dermatitis 1985;13(3):192-193. PubMed
  17. Skrebova, N., Brocks, K., and Karlsmark, T. Allergic contact cheilitis from spearmint oil. Contact Dermatitis 1998;39(1):35. PubMed
  18. Damiani E, Aloia AM, Priore MG, et al. Allergy to mint (Mentha spicata). J Investig Allergol Clin Immunol 2012;22:309-10.
  19. Connelly AE, Tucker AJ, Tulk H, et al. High-rosmarinic acid spearmint tea in the management of knee osteoarthritis symptoms. J Med Food 2014;17:1361-7. PubMed
  20. Lasrado JA, Nieman KM, Fonseca BA, et al. Safety and tolerability of a dried aqueous spearmint extract. Regul Toxicol Pharmacol 2017;86:167-176. PubMed

See these in context on the Spearmint 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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