Krill Oil
Generic name: omega-3 polyunsaturated fatty acids
Brand names: Mercola Krill Oil, Schiff MegaRed Omega-3 Krill Oil, Neptune Krill Oil, Red Whale Krill Oil
Medically reviewed by Drugs.com. Last updated on Sep 10, 2024.
What is Krill Oil?
Krill is a small crustacean with an appearance similar to shrimp. They are found in the colder waters of the ocean. Krill primarily serve as a food source for other animals in the ocean, for example - whales, seals, penguins, squid and fish.
Krill is found in the oceans off of Antarctica, Canada, and Japan. Harvesting of krill is controversial. There is concern that commercial harvesting of Krill for use in Krill Oil supplements could threaten the species that consume it for food, including whales. All krill oil sold in nutritional supplements is harvested out of the open ocean, upsetting the natural balance of food supplies for larger marine animals.
Commercial uses of Krill include salmon aquaculture farming, harvesting for use in Krill Oil capsules, as food for home aquariums, and as a human food source. Krill, known as Okiami has been harvested by the Japanese as a human food source since the 19th century, and is also consumed in South Korea and Taiwan. Krill has a pink or red appearance due to the plankton that they consume as a food source in the ocean.1
What is in Krill Oil?
Krill contains an oil that is similar to the oils found in fish oils, the omega-3 fatty acids. Omega-3 fatty acids are recommended for use in lowering triglyceride levels. Krill Oil use as a supplement to lower blood lipids is increasing in popularity.1
Krill Oil contains:
- The omega-3 polyunsaturated fatty acids EPA (Eicosapentaenoic Acid) and DHA (Docosahexaenoic). Omega-3 polyunsaturated fatty acids are also found in oils from certain types of fish, vegetables, and other plant sources.
Unlike fish oil, the omega-3 fatty acids in Krill oil are absorbed and carried to the body's cells in phospholipid form. Omega-3 fatty acids, in combination with diet and exercise, work by lowering the body's production of “bad”, low density lipoprotein (LDL) and triglycerides, and may raise high density lipoprotein (HDL) “good” cholesterol. High levels of cholesterol and triglycerides can lead to coronary artery disease, heart disease, and stroke.
Supportive, but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease.
Krill Oil also contains:
- Phospholipid-derived fatty acids (PLFA), which may result in better absorption, and marine lethicin2
- A carotenoid antioxidant called astaxanthin. Antioxidants inhibit oxidation and may neutralize the oxidant effect of free radicals and other substances in body tissues that may lead to disease.
Krill Oil has also been used to treat high blood pressure, stroke, cancer, osteoarthritis, depression and premenstrual syndrome (PMS), although high quality studies with adequately sized populations validating these uses are lacking. Patients should speak with their physician prior to using Krill Oil for any condition.
Warnings issued by the FDA note that certain fish (marlin, tuna, swordfish) may contain toxins such as methylmercury, leading some consumers to be wary of eating fish to obtain omega-3 fatty acids. Manufacturers of Krill Oil suggest it may be safer due to lower levels of contaminants such as mercury. The FDA has issued recommendations that women who are pregnant or planning to become pregnant, and young children avoid eating more than 6 ounces of fish per week. However, Krill may also contain methylmercury and other pollutants from sea water, although they are lower on the food chain and may contain lower values of such pollutants. One study noted that Krill harvested from Antarctica contains high levels of organic pesticides.3
Manufacturers of Krill Oil claim one of the advantages of Krill Oil over Fish Oil is that it does not lead to the fishy aftertaste, reflux or belching of fish flavors, a common side effect with fish oil supplements. However, Krill Oil may still lead to these side effects in some patients.
The U.S. Food and Drug Administration (FDA) has not specifically made recommendations on Krill Oil safety or effectiveness. Krill Oil is considered a dietary supplement and does not require a prescription.1,4,5,6,7,8
Krill Oil may also be used for purposes not listed in this medication guide.
Warnings
Take Krill Oil exactly as directed on the label, or as prescribed by your doctor. Do not take it in larger amounts or for longer than recommended.
Krill Oil should not be used in patients with a fish or shrimp allergy, or probably any other type of seafood. Tests for susceptibility to allergic reactions to Krill Oil have not been completed.
People with coagulopathy or taking anticoagulants or other medications should notify their physician prior to taking dietary supplements.
Stop taking Krill Oil at least two weeks prior to any scheduled surgery or procedure.
Swallow the Krill Oil capsule whole. Do not puncture or open the capsule.
Marine Oils, such as Krill Oil, is only part of a complete program of treatment that also includes diet, exercise, and weight control. Follow your diet, medication, and exercise routines very closely.1
There may be other drugs that can interact with Krill Oil. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.
Stop using Krill Oil and get emergency medical help if you think you have used too much medicine, or if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Less serious side effects are more likely, and you may have none at all. Talk to your doctor about any side effect that seems unusual or is especially bothersome.
Before Taking Krill Oil
Do not use Marine Oils like Krill Oil if you are allergic to fish, shrimp or any other type of seafood. Be sure to check the label on the Krill Oil package to look for other active or inactive ingredients that may cause an allergy. If you are not sure, ask your pharmacist.
Ask a doctor or pharmacist about using this medicine if you have:
- Diabetes
- Liver disease
- A pancreas disorder
- Blood clotting disorder or risk of stroke
- Upcoming surgery or procedure that might increase your risk for bleeding
- Underactive thyroid
- If you drink more than two alcoholic beverages per day
It is not known whether Krill Oil will harm an unborn baby, although certain prescription omega-3 fatty acids (Lovaza) have a Pregnancy Rating C. Tell your doctor if you are pregnant or plan to become pregnant while using Krill Oil. It is not known whether omega-3 polyunsaturated fatty acids pass into breast milk or if this could harm a nursing baby. Do not use Krill Oil without telling your doctor if you are breast-feeding a baby. Do not give this medication to anyone under 18 years old.1
See also: Fish Oil and Pregnancy and Breastfeeding Warnings (in more detail)
How should I take Krill Oil?
Use Krill Oil exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.
Swallow the Krill Oil capsule whole. Do not puncture or open the capsule. Krill Oils may work best if taken with with food, although
Marine Oils like Krill Oil are only part of a complete program of treatment that also includes diet, exercise, and weight control. Follow your diet, medication, and exercise routines very closely.
Store Krill Oil at room temperature away from moisture and heat. Do not freeze.
What Happens if I Miss a Dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What Happens if I Overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What to avoid
Avoid eating foods that are high in fat or cholesterol. Krill Oil will not be as effective in lowering your triglycerides if you do not follow the diet plan recommended by your doctor.
Avoid drinking alcohol. It can increase triglycerides and may make your condition worse.
Krill Oil Side Effects
Get emergency medical help if you have any of these signs of an allergic reaction to Krill Oil: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using Fish Oil and call your doctor at once if you have any of these serious side effects:
- Fever, chills, body aches, flu symptoms
- Chest pain
- Uneven heartbeats
Less serious Krill Oil side effects may include:
- Back pain
- Mild skin rash
- Fishy aftertaste or belching in some patients
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.1
What Other Drugs Will Affect Fish Oil?
Tell your doctor about all other medicines you use, especially:
- Estrogens (birth control pills or hormone replacement)
- A blood thinner such as warfarin (Coumadin, Jantoven)
- Aspirin or NSAIDS (naproxen, ibuprofen, Aleve, Motrin IB, Advil)
- A beta-blocker such as atenolol (Tenormin, Tenoretic), carvedilol (Coreg), labetalol (Normodyne, Trandate), metoprolol (Dutoprol, Lopressor, Toprol), nadolol (Corgard), propranolol (Inderal, InnoPran), sotalol (Betapace), and others, or
- A diuretic (water pill) such as chlorothiazide (Diuril), hydrochlorothiazide (HydroDIURIL, Microzide), chlorthalidone (Hygroton, Thalitone), indapamide (Lozol), metolazone (Mykrox, Zaroxolyn), and others
- Orlistat (Xenical, Alli) for weight loss
This list is not complete and other drugs may interact with Fish Oil. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.1
Further information
Your pharmacist or physician can provide more information about Krill Oil.
References
- Drugs.com. Omega-3 Polyunsaturated Fatty Acids. Accessed Jan. 21, 2013. https://www.drugs.com/mtm/omega-3-polyunsaturated-fatty-acids.html
- Schuchardt JP, Schneider I, Meyer H, et al. Incorporation of EPA and DHA into plasma phospholipids in response to different omega-3 fatty acid formulations, a comparative bioavailability study of fish oil vs. krill oil. Lipids Health Dis. 2011; 10:145. Accessed Jan. 21, 2013 at http://www.ncbi.nlm.nih.gov/pubmed/21854650
- Corsolini S, Covaci A, Ademollo N, et al. Occurrence of organochlorine pesticides (OCPs) and their enantiomeric signatures, and concentrations of polybrominated diphenyl ethers (PBDEs) in the Adélie penguin food web, Antarctica. Environmental Pollution 2006; 140:371-82.
- Caring for Cancer. Krill Oil. Alternative Medicine. Accessed Jan. 21, 2013. Last updated Feb. 2011. https://www.caring4cancer.com/myhealthcenter/tools/knowledgebase/Article.aspx?Hwid=hn-10002454
- Ulven SM, Kirkhus B, Lamglait A, et al. Metabolic effects of krill oil are essentially similar to those of fish oil but at lower dose of EPA and DHA, in healthy volunteers. Lipids. 2011;46:37-46. Accessed Jan. 21, 2013 at http://www.ncbi.nlm.nih.gov/pubmed/21042875
- Deutsch L. Evaluation of the effect of Neptune Krill Oil on chronic inflammation and arthritic symptoms. J Am Coll Nutr. 2007;26:39-48
- Bunea R, El Farrah K, Deutsch L. Evaluation of the effects of neptune krill oil on the clinical course of hyperlipidemia. Altern. Med. Rev. 2004;9:420-8
- Sampalis F, Bunea R, Pelland MF, et al. Evaluation of the effects of neptune krill oil on the management of premenstrual syndrome and dysmenorrhea. Altern. Med. Rev. 2003;8:171-9.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.