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Fish Oil Side Effects

Generic name: omega-3 polyunsaturated fatty acids

Medically reviewed by Drugs.com. Last updated on Sep 22, 2023.

Note: This document contains side effect information about omega-3 polyunsaturated fatty acids. Some dosage forms listed on this page may not apply to the brand name Fish Oil.

Applies to omega-3 polyunsaturated fatty acids: oral capsule.

Serious side effects of Fish Oil

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Other side effects of Fish Oil

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

For Healthcare Professionals

Applies to omega-3 polyunsaturated fatty acids: oral capsule, oral delayed release capsule, oral kit, oral liquid, oral tablet chewable.

Gastrointestinal

Common (1% to 10%): Eructation, dyspepsia, nausea, gastrointestinal disorders (including abdominal distension, abdominal pain, constipation, diarrhea, flatulence, gastroesophageal reflux disease, vomiting)

Uncommon (0.1% to 1%): Gastrointestinal hemorrhage, gastroenteritis

Rare (less than 0.1%): Gastrointestinal pain

Very rare (less than 0.01%): Lower gastrointestinal hemorrhage[Ref]

General

The most common adverse events were eructation, dyspepsia, and taste perversion[Ref]

Other

Common (1% to 10%): Infection, pain

Uncommon (0.1% to 1%): Death[Ref]

Dermatologic

Common (1% to 10%): Rash

Uncommon (0.1% to 1%): Atopic dermatitis

Rare (less than 0.1%): Urticaria, acne, rash pruritic

Frequency not reported: Pruritus[Ref]

Cardiovascular

Uncommon (0.1% to 1%): Hypotension[Ref]

Musculoskeletal

Common (1% to 10%): Back pain[Ref]

Metabolic

Uncommon (0.1% to 1%): Hyperglycemia, gout, high triglycerides

Very rare (less than 0.01%): Blood lactate dehydrogenase increased[Ref]

Nervous system

Common (1% to 10%): Taste perversion

Uncommon (0.1% to 1%): Dizziness, dysgeusia, headache, hyperactivity[Ref]

Respiratory

Uncommon (0.1% to 1%): Epistaxis

Very rare (less than 0.01%): Nasal dryness

Frequency not reported: Influenza[Ref]

Hypersensitivity

Rare (less than 0.1%): Hypersensitivity

Postmarketing reports: Anaphylactic reaction[Ref]

Hematologic

Very rare (less than 0.01%): White blood count increased,

Frequency not reported: Slight prolongation of bleeding time

Postmarketing reports: Hemorrhagic diathesis[Ref]

Psychiatric

Uncommon (0.1% to 1%): Tics, tantrum, insomnia[Ref]

Hepatic

Rare (less than 0.1%): Liver disorders (including increased ALT, increased AST, and transaminases increased)[Ref]

Frequently asked questions

References

1. Cerner Multum, Inc. UK Summary of Product Characteristics.

2. Cerner Multum, Inc. Australian Product Information.

3. Product Information. Lovaza (omega-3 polyunsaturated fatty acids). GlaxoSmithKline. 2012.

4. Product Information. Vayarin (omega-3 polyunsaturated fatty acids). Vaya Pharma. 2017.

5. Product Information. Omega-3-Acid Ethyl Esters (omega-3 polyunsaturated fatty acids). Apotex Corporation. 2017.

6. Product Information. Omega-3 D-3 Wellness Pack (omega-3 polyunsaturated fatty acids). TMIG Inc. 2017.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.