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Dietary supplement

Shark Cartilage Ingredients & Drug Interactions

by Douglas Laboratories

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

First and foremost: checking Shark Cartilage 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

Shark Cartilage is a dietary supplement by Douglas Laboratories with 1 active ingredient. Its ingredients are commonly taken for cancer support (popular use), arthritis and joint pain, psoriasis.Based on those ingredients, 121 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Shark Cartilage. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Shark Cartilage by Douglas Laboratories

Ask about any prescription or over-the-counter medication and we check it for interactions with Shark Cartilage by Douglas Laboratories — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Shark Cartilage by Douglas Laboratories

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

From our pharmacy team — supplement deep dive

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

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

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

This product contains one active ingredient: shark cartilage. It's a single-ingredient supplement, with the cartilage enclosed in gelatin capsules along with cellulose, vegetable stearate, and silica (inactive binders and flow agents).

Does it work?

Couldn't assess
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 assessable

This is a single-ingredient Shark Cartilage product and its label doesn't state a use — see Shark Cartilage's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The evidence for shark cartilage is thin. For cancer, it's rated likely ineffective.

For age-related macular degeneration, diabetic retinopathy, Kaposi sarcoma, osteoarthritis, and psoriasis, there isn't enough reliable evidence to say whether it works or doesn't.

The evidence, ingredient by ingredient Shark Cartilage

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.

Taken by mouth, shark cartilage is generally well tolerated, but side effects do happen. The most common ones are constipation, dizziness, indigestion, nausea, vomiting, taste changes, and fatigue.

A small number of people have reported more serious effects like altered consciousness, weakness, decreased sensation, liver inflammation, abnormal blood sugar levels, and swelling in the legs and feet. The safety data isn't strong enough to know whether it's safe during pregnancy or breastfeeding.

The facts advise against it in both situations. Talk with your doctor or pharmacist before using it if you're pregnant, planning to become pregnant, or breastfeeding.

Side effects, ingredient by ingredient Shark Cartilage

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 — Shark Cartilage.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: immunosuppressants / transplant drugs.
  • For scale: 121 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.

Immunosuppressants (Moderate severity): shark cartilage may theoretically interfere with these drugs' ability to dampen your immune system. If you take any immunosuppressant, check the specific medication with your doctor or pharmacist before using this product.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Shark cartilage is poorly studied and lacks proven benefits for most conditions people try it for. If you take immunosuppressants, you need to check with your doctor or pharmacist before starting it.

Most people who take it tolerate it okay, but digestive upset and other side effects do occur. Have a conversation with your own healthcare provider about whether this product makes sense for you.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2012.

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 Shark Cartilage, straight from the product label.

Brand Douglas Laboratories
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Jun 25, 2012
DSLD ID 10068
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Dairy Free, Sugar 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 Shark Cartilage by Douglas Laboratories, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
60
IngredientAmount% DV
Shark Cartilage740 mg--

Other ingredients: Gelatin, Cellulose, Vegetable 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.
FDA Statement of Identity

A Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested Usage: As a dietary supplement, adults take 1 capsule for every 11 pounds of body weight for the first 3 weeks - NOT TO EXCEED 18 CAPSULES DAILY. Take in equal amounts 15 minutes before meals. Thereafter take 4 to 6 capsules daily or as directed by physician.

Precautions

KEEP OUT OF REACH OF CHILDREN.

Tamper resistant package, do not use if outer seal is missing.

Storage

For optimal storage conditions, store in a cool, dry place. (59(0)-77(0)F/15(0)-25(0)C) (35-65% relative humidity)

General

Formula #81821

Formulation

This product contains NO yeast, wheat gluten, soy protein, milk/dairy, corn, sodium, sugar, starch, artificial coloring, preservatives or flavoring.

General Statements

Meets Douglas Laboratories spec [#81821]. Conforms to USP <2091> for weight. Meets USP <2040> for disintegration.

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

See for yourself

Shark Cartilage by Douglas Laboratories label

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

Shark Cartilage 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 Shark Cartilage by Douglas Laboratories

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

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

Shark Cartilage

Interacts with
121 drugs
740 mg per serving Form: Fish, Shark Cartilage

Shark cartilage is a supplement made from the skeletal tissue of sharks that was heavily promoted for cancer and joint conditions, but good-quality cl...

Shark Cartilage monograph & interactions

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

Interaction report

Shark Cartilage by Douglas Laboratories Drug Interactions

Want to check YOUR meds against Shark Cartilage?

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
121Drugs
121 Moderate

Ingredients driving the most interactions

Shark Cartilage 121

Individual Drug Interactions

The ingredients in Shark Cartilage interact with 121 drugs. Click any drug to see the details.

1 of the 1 ingredient in Shark Cartilage interact with drugs. Each result below shows which ingredient is responsible. Shark Cartilage

Each ingredient & the kinds of drugs it affects

For each ingredient in Shark Cartilage 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.

Shark Cartilage1 drug type · 121 drugs

Immunosuppressants

Theoretically, shark cartilage might interfere with immunosuppressive therapy.
In vitro evidence suggests that shark cartilage might stimulate immune responses. This effect has not been reported in humans.

Likelihood Possible Evidence D
Shark Cartilage full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Shark Cartilage, from the product label.

Douglas Laboratories

See all Douglas Laboratories products
Name
Douglas Laboratories
City
Pittsburgh
State
PA
ZipCode
15205
Web Address
www.douglaslabs.com
Pharmacist Counseling Corner

Shark Cartilage by Douglas Laboratories: Common Questions

Does Shark Cartilage by Douglas Laboratories interact with any medications?
Yes. Based on its ingredients, Shark Cartilage has a known interaction with 121 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Shark Cartilage contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What is shark cartilage supposed to do?
Shark cartilage is marketed for conditions like cancer, arthritis, and eye problems. The evidence, though, is weak. For cancer it's rated likely ineffective, and for the others there just isn't enough reliable evidence to know if it works.
What side effects might I have?
Common ones are constipation, nausea, vomiting, indigestion, dizziness, taste changes, and fatigue. Rarely, people report more serious effects like weakness, altered consciousness, liver inflammation, or abnormal blood sugar. Stop and talk to your doctor if you notice anything concerning.
Can I take this while pregnant or breastfeeding?
The safety data isn't strong enough to know either way. The available information advises against it in both cases. Talk with your doctor or pharmacist for personalized advice if you're pregnant, planning to become pregnant, or breastfeeding.
Does this product have any fillers?
The capsule itself and the ingredients that hold it together—gelatin, cellulose, vegetable stearate, and silica—are all present. If you have sensitivities to any of these, check the label or ask your pharmacist.

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.

Shark Cartilage label
Go deeper

The Full Monographs Behind Shark Cartilage’s Ingredients

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

Herb & supplement monograph

Shark Cartilage

Interacts with 121 drugs

Shark cartilage is a supplement made from the skeletal tissue of sharks that was heavily promoted for cancer and joint conditions, but good-quality clinical trials have not shown meaningful...

Read the full Shark Cartilage monograph →
Sources

Sources & How We Checked

Shark Cartilage'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 12 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.

Shark Cartilage 12 references
  1. Ashar B, Vargo E. Shark cartilage-induced hepatitis [letter]. Ann Intern Med 1996;125:780-1. PubMed
  2. Lane IW, Comac L. Sharks don't get cancer. Garden City, NY: Avery Publishing Group; 1992.
  3. Miller DR, Anderson GT, Stark JJ, et al. Phase I/II trial of the safety and efficacy of shark cartilage in the treatment of advanced cancer. J Clin Oncol 1998;16:3649-55. PubMed
  4. Leitner SP, Rothkopf MM, Haverstick L, et al. Two phase II studies of oral dry shark cartilage powder (SCP) in patients (pts) with either metastatic breast or prostate cancer refractory to standard treatment. Proc Am Soc Clinical Oncol 1998;17:A240.
  5. Batist G, Patenaude F, Champagne P, et al. Neovastat (AE-941) in refractory renal cell carcinoma patients: report of a phase II trial with two dose levels. Ann Oncol 2002;13:1259-63..
  6. Merly, L., Simjee, S., and Smith, S. L. Induction of inflammatory cytokines by cartilage extracts. Int Immunopharmacol. 2007;7(3):383-391. PubMed
  7. Bargahi, A., Hassan, Z. M., Rabbani, A., Langroudi, L., Noori, S. H., and Safari, E. Effect of shark cartilage derived protein on the NK cells activity. Immunopharmacol.Immunotoxicol. 2011;33(3):403-409. PubMed
  8. Leitner SP, Rothkopf MM, Haverstick DD, and et al. Two phase II studies of oral dry shark cartilage powder (SCP) in patients with either metastatic breast or prostate cancer refractory to standard treatment. Amer Soc Clin Oncol 1998;17:A240.
  9. Milner M. A guide to the use of shark cartilage in the treatment of arthritis and other inflammatory joint diseases. Amer Chiropractor 1999;21:40-42.
  10. Rosenbluth, RJ, Jennis, AA, Cantwell, S, and et al. Oral shark cartilage in the treatment of patients with advanced primary brain tumors. A phase II pilot study (meeting abstract). Proc Annu Meet Am Soc Clin Oncol 1999;18:A554.
  11. Saad F, Klotz L, Babaian R, Lacombe L, Champagne P, and Dupont E. Phase I/II trial on AE-941 (Neovastat) in patients with metastatic refractory prostate cancer (abstract presentation). Canadian Urological Association Annual Meeting (June 24-27, 2001).
  12. Merly L, Smith SL. Pro-inflammatory properties of shark cartilage supplement. Immunopharmacol Immunotoxicol. 2015;37(2):140-7. PubMed

See these in context on the Shark Cartilage 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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