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Dietary supplement

Astaxanthin 4 mg Ingredients & Drug Interactions

by NOW

Astaxanthin 4 mg label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Astaxanthin 4 mg 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

Astaxanthin 4 mg is a dietary supplement by NOW with 1 active ingredient. Its ingredients are commonly taken for antioxidant support, skin health and aging, eye health.Based on those ingredients, 671 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Astaxanthin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Astaxanthin 4 mg by NOW

Ask about any prescription or over-the-counter medication and we check it for interactions with Astaxanthin 4 mg by NOW — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Astaxanthin 4 mg by NOW

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: astaxanthin 4 mg per capsule. Astaxanthin is a carotenoid — a pigment found naturally in algae and seafood — that acts as an antioxidant in your body.

The capsule also holds two inactive ingredients (organic inulin and vegetable polysaccharide) as fillers and binders.

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 Astaxanthin's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: cellular free radical protection and immune support.
  • We looked for evidence on: Exercise-induced muscle damage, Exercise-induced muscle soreness, Heart failure, Hyperlipidemia, Hypertension, Rheumatoid arthritis (RA) — and 4 related terms.
  • The closest evidence on file: Astaxanthin is rated "Insufficient Reliable Evidence To Rate" for Heart failure (Natural Medicines).
  • Also on file: Astaxanthin is rated "Insufficient Reliable Evidence To Rate" for Exercise-induced muscle soreness, Hyperlipidemia, Hypertension, Rheumatoid arthritis (RA), and more.

The data we hold doesn't establish that astaxanthin is effective for any of the conditions it's marketed for — including age-related cognitive decline, macular degeneration, aging skin, Alzheimer's disease, athletic performance, or carpal tunnel syndrome. For each of these, the evidence is rated insufficient to draw a reliable conclusion.

That doesn't mean it doesn't work; it means the research we have isn't solid enough to say either way.

The evidence, ingredient by ingredient Astaxanthin

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.

Astaxanthin is generally well tolerated in studies, though long-term safety data are limited. The most common side effects are mild: abdominal pain, diarrhea, and red-colored stools (which is harmless and happens because astaxanthin is a red pigment).

At much higher doses — 40 mg daily — severe stomach pain has been reported in a small number of cases. There isn't enough safety data to know whether astaxanthin is safe during pregnancy or while breastfeeding.

The safety data advises against use in both situations. Talk with your doctor or pharmacist for personalized advice if you're pregnant, planning pregnancy, or nursing.

Side effects, ingredient by ingredient Astaxanthin

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 — Astaxanthin.
  • The most serious interaction on file is rated Moderate.
  • For scale: 672 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.

You should check whether you take any drugs metabolized by CYP3A4 enzymes (a very broad group including certain blood pressure medications, statins, and immunosuppressants) or CYP2B6 enzymes before starting this product. While this effect hasn't been proven in humans, astaxanthin may theoretically lower their levels and reduce effectiveness.

Use the medication checker below with your exact drug names.

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.

Astaxanthin is a single-ingredient antioxidant supplement that's generally well tolerated at the 4 mg dose in this product. However, it may theoretically interact with a large number of medications by affecting how your liver breaks them down.

Before you start, check your medications with the tool on this page — and definitely talk to your pharmacist if you're on multiple prescription drugs or blood pressure and heart medications.

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 Aug 23, 2019.

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 Astaxanthin 4 mg, straight from the product label.

Brand NOW
Barcode (UPC) 733739023063
Net contents 90 Veg Capsule(s)
Market status On market
Date entered into DSLD Aug 23, 2019
DSLD ID 205705
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Organic, 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 Astaxanthin 4 mg by NOW, 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 Veg Capsule(s)
Maximum serving Sizes:
1 Veg Capsule(s)
UPC/BARCODE
733739023063
IngredientAmount% DV
Total Carbohydrates1 Gram(s)1%
Astaxanthin4 mg--

Other ingredients: organic Inulin, Vegetable Polysaccharide

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.
Suggested/Recommended/Usage/Directions

Suggested usage: Take 1 capsule 1 to 3 times daily with food.

Formula

Astaxanthin is a naturally occurring carotenoid that, due to its unique structure, performs an important role in cellular free radical protections and healthy immune system responses. This astaxanthin is derived from organic Haematococcus pluvialis microalgae. This whole food algae source has naturally occurring lutein, zeaxanthin, canthaxanthin and beta-carotene.

Made with Organic Algae

AstaZine The world's purest natural Astaxanthin

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.

Precautions

Caution: For adults only.

Consult physician if pregnant/nursing, taking medication.

Keep out of reach of children.

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

Brand IP Statement(s)

AstaZine is a registered trademark of Algae Health Sciences, Inc.

General Statements

Cellular protection Potent free radical neutralizer

General health Family owned since 1968.

FDA Statement of Identity

A Dietary Supplement

Formulation

Vegetarian/Vegan

Non GMO

Certified Organic by QAI.

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients.

Seals/Symbols

Non GMO Project Verified nongmoproject.org

GMP Quality Assured

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

See for yourself

Astaxanthin 4 mg by NOW label

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

Astaxanthin 4 mg 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 Astaxanthin 4 mg by NOW

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

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

Astaxanthin

Interacts with
671 drugs
4 mg per serving Form: organic Haematococcus pluvialis

Astaxanthin is a reddish carotenoid pigment with strong antioxidant activity in the lab, and it is widely promoted for skin, eye, heart, and exercise...

Astaxanthin monograph & interactions

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

Interaction report

Astaxanthin 4 mg by NOW Drug Interactions

Want to check YOUR meds against Astaxanthin 4 mg?

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
671Drugs
671 Moderate

Ingredients driving the most interactions

Astaxanthin 671

Individual Drug Interactions

The ingredients in Astaxanthin 4 mg interact with 671 drugs. Click any drug to see the details.

1 of the 1 ingredient in Astaxanthin 4 mg interact with drugs. Each result below shows which ingredient is responsible. Astaxanthin

Each ingredient & the kinds of drugs it affects

For each ingredient in Astaxanthin 4 mg 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.

Astaxanthin2 drug types · 671 drugs

Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, astaxanthin may decrease levels of drugs metabolized by CYP2B6.
In vitro research shows that astaxanthin induces cytochrome CYP2B6 enzyme activity in human hepatocytes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, astaxanthin may decrease levels of drugs metabolized by CYP3A4.
In vitro research shows that astaxanthin induces CYP3A4 enzyme activity in human hepatocytes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Astaxanthin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Astaxanthin 4 mg, from the product label.

NOW

See all NOW products
Name
NOW Foods
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
nowfoods.com
Pharmacist Counseling Corner

Astaxanthin 4 mg by NOW: Common Questions

Does Astaxanthin 4 mg by NOW interact with any medications?
Yes. Based on its ingredients, Astaxanthin 4 mg has a known interaction with 671 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Astaxanthin 4 mg 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 exactly is astaxanthin and where does it come from?
Astaxanthin is a natural pigment called a carotenoid — the same family as beta-carotene. You'll find it in algae, salmon, and shrimp, which is why those foods have a reddish color. In supplements, it's usually harvested from algae.
Will astaxanthin turn my poop red?
It might. Red or orange-colored stools are a documented side effect, but they're harmless — it's just the pigment coming through. This is more likely at higher doses.
Is astaxanthin safe if I'm pregnant or breastfeeding?
There isn't enough safety data to know. The data we have advises against use during pregnancy and while breastfeeding. Talk with your doctor or pharmacist about your situation — they can give you personalized advice.
What conditions does astaxanthin actually work for?
We don't have reliable evidence that it works for any of the conditions it's marketed for — aging skin, brain health, athletic performance, and others. That means the research so far isn't solid enough to say yes or no.
Are there other ingredients or fillers in this capsule?
Besides the 4 mg of astaxanthin, the capsule contains organic inulin and vegetable polysaccharide as binders and fillers. There are no other active ingredients.

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

Not sure if Astaxanthin 4 mg is safe with your meds?

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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.

Astaxanthin 4 mg label
Go deeper

The Full Monographs Behind Astaxanthin 4 mg’s Ingredients

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

Herb & supplement monograph

Astaxanthin

Interacts with 671 drugs

Astaxanthin is a reddish carotenoid pigment with strong antioxidant activity in the lab, and it is widely promoted for skin, eye, heart, and exercise benefits. Early human studies are promis...

Read the full Astaxanthin monograph →
Sources

Sources & How We Checked

Astaxanthin 4 mg'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 3 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.

Astaxanthin 3 references
  1. Kupcinskas L, Lafolie P, Lignell A, et al. Efficacy of the natural antioxidant astaxanthin in the treatment of functional dyspepsia in patients with or without Helicobacter pylori infection: A prospective, randomized, double blind, and placebo-controlled
  2. Kistler, A., Liechti, H., Pichard, L., Wolz, E., Oesterhelt, G., Hayes, A., and Maurel, P. Metabolism and CYP-inducer properties of astaxanthin in man and primary human hepatocytes. Arch.Toxicol. 2002;75(11-12):665-675. PubMed
  3. Choi HD, Youn YK, Shin WG. Positive effects of astaxanthin on lipid profiles and oxidative stress in overweight subjects. Plant Foods Hum Nutr. 2011;66:363-369. PubMed

See these in context on the Astaxanthin 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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