Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Astaxanthin 4 mg Ingredients & Drug Interactions

by NOW

Astaxanthin 4 mg label
See full label image
Softgel 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 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 AstaReal. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

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.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

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 supplement contains one active ingredient: AstaReal astaxanthin, a carotenoid (a plant pigment) at 4 mg per softgel. The inactive ingredients are organic extra virgin olive oil, bovine gelatin, glycerin, water, and mixed tocopherols (vitamin E).

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: Age-related macular degeneration (AMD), Aging skin, Athletic performance, Diabetes, Dry eye, Exercise-induced muscle damage — and 4 related terms.
  • The closest evidence on file: Astaxanthin is rated "Insufficient Reliable Evidence To Rate" for Age-related macular degeneration (AMD) (Natural Medicines).
  • Also on file: Astaxanthin is rated "Insufficient Reliable Evidence To Rate" for Aging skin, Athletic performance, Heart failure, Diabetes, and more.

The evidence we hold doesn't establish that astaxanthin works for the conditions listed — age-related cognitive decline, macular degeneration, aging skin, Alzheimer disease, athletic performance, and carpal tunnel syndrome all have insufficient reliable evidence to rate it. That doesn't mean it won't help; it means large, well-designed human studies haven't been done or published yet.

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 reported are abdominal pain, diarrhea, and red-colored stool (from the pigment itself).

A small number of trial participants at higher doses experienced increased bowel movements or stomach pain. There isn't enough safety data to know whether astaxanthin is safe in pregnancy or while breastfeeding.

If you're pregnant, planning to become pregnant, or nursing, talk with your doctor or pharmacist before taking this product.

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.

Before you start, double-check any drugs your liver breaks down, especially those metabolized by CYP3A4 (the bigger group) and CYP2B6. These are Moderate-severity interactions based on lab data — not yet seen in people, but worth confirming with your pharmacist that your specific medications aren't affected.

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 well-tolerated antioxidant pigment that may appeal to you if you're interested in age-related wellness. If you take any prescription medications metabolized by your liver — especially blood pressure drugs or statins — check this product against your exact medications first.

Always talk with your pharmacist before adding it to your routine.

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 Oct 24, 2024.

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) 733739023056
Net contents 90 Softgel(s)
Market status On market
Date entered into DSLD Oct 24, 2024
DSLD ID 313567
Product type Non-nutrient/non-botanical
Supplement form Softgel Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Kosher, 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 Softgel(s)
Maximum serving Sizes:
1 Softgel(s)
Servings per container
90
UPC/BARCODE
733739023056
IngredientAmount% DV
Calories5 Calorie(s)--
AstaReal4 mg--

Other ingredients: organic extra virgin Olive Oil, Bovine Gelatin, Glycerin, Water, Mixed Tocopherols

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 softgel daily with a fat-containing meal.

Formula

Astaxanthin is a naturally occurring carotenoid that, due to its unique structure, performs an important role in cellular free radical protection and healthy immune system responses. NOW Astaxanthin is derived from Non-GMO Haematococcus pluvialis microalgae.

Potent free radical neutralizer AstaReal

Triangle K (Kosher) Contains Gelatin

Triangle K (Kosher) Contains Gelatin

Formulation

NOW Astaxanthin is derived from Non-GMO Haematococcus pluvialis microalgae.

Natural color variation may occur in this product.

Cellular Protection Supports balanced Immune system responses

Non-GMO

Made and quality tested in the USA with globally sourced ingredients.

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

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, or have a medical condition.

Keep out of reach of children.

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

Brand IP Statement(s)

AstaReal is a registered trademark of Fuji Chemical Industries Co., Ltd.

General Statements

This bottle is made from 100% PCR (post-consumer recycled) resin.

General Health Family owned since 1968.

FDA Statement of Identity

A Dietary Supplement

Seals/Symbols

Triangle K (Kosher) Contains Gelatin

GMP Quality Assured

Storage

Store in a cool, dry place after opening.

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 Softgel(s) Dosage formSoftgel Capsule Servings per container90 Amounts shown are per serving.

AstaReal

Interacts with
671 drugs
4 mg per serving Form: Astaxanthin

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

AstaReal monograph & interactions

Other (inactive) ingredients: Organic extra virgin Olive Oil, Bovine Gelatin, Glycerin, Water, Mixed Tocopherols. 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

AstaReal 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. AstaReal

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.

AstaReal2 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
AstaReal 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 actually is astaxanthin?
It's a carotenoid — a natural pigment from certain algae and seafood. Your body can't make it, so you get it only from food or supplements. That red color in salmon and shrimp comes from astaxanthin.
Will this help with brain aging or memory loss?
The evidence we have isn't strong enough to say. Astaxanthin for age-related cognitive decline, Alzheimer disease, and similar conditions all have insufficient reliable evidence to rate.
Can I take this while pregnant or nursing?
There isn't enough safety data to know either way. If you're pregnant, planning to get pregnant, or breastfeeding, talk with your doctor or pharmacist before using it.
What are the most common side effects?
Most people tolerate it well. The side effects reported in studies are mild — abdominal pain, diarrhea, and red-colored stool. The color comes from the pigment itself and is harmless.
Why is the stool sometimes red?
Astaxanthin is a bright red-orange pigment. When your body doesn't absorb all of it, some passes through and colors your stool. It's completely normal and not a sign of anything wrong.

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

Not sure if Astaxanthin 4 mg 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.

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

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team