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Fish Side Effects

The most commonly reported side effects of fish include fatigue, diarrhoea, and nausea, based on 99,327 FDA adverse event reports from 2004 to 2025. 5.8% of reports found the drug to be ineffective.

Fish side effects

Percentages show how often each reaction appears relative to total reports for fish.

1
Fatigue8.2%8,130
2
Diarrhoea5.9%5,867
3
Drug Ineffective5.8%5,767
4
Nausea5.6%5,561
5
Headache5.5%5,495
6
Pain5.1%5,095
7
Dizziness4.5%4,442
8
Arthralgia4.4%4,371
9
Dyspnoea4.1%4,049
10
Off Label Use4.0%3,952
11
Asthenia3.9%3,866
12
Rash3.7%3,649
13
Pruritus3.5%3,454
14
Vomiting3.2%3,143
15
Insomnia3.1%3,077

These are voluntary reports and do not establish that fish caused these reactions.

Report severity

50.0%Serious49,625 reports
21.5%Hospitalizations21,338 reports
4.9%Fatal4,886 reports

Seriousness is determined by the reporter, not by OpenClaim.

Fish drug interactions

Other drugs that appear in adverse event reports alongside fish. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Adalimumab6.8%6,710
2
Lenalidomide5.5%5,506
3
Sodium-oxybate4.1%4,038
4
Etanercept4.0%3,936
5
Niacin3.4%3,389
6
Tofacitinib2.4%2,375
7
Certolizumab-pegol2.0%1,999
8
Abatacept2.0%1,945
9
Methotrexate1.9%1,929
10
Acetaminophen1.9%1,914
11
Dupilumab1.9%1,914
12
Prednisone1.9%1,909
13
Naproxen1.8%1,798
14
Apremilast1.8%1,768
15
Infliximab1.8%1,740

Taken alongside

1
Ergocalciferol39.4%39,086
2
Aspirin30.8%30,578
3
Calcium20.7%20,521
4
Acetaminophen17.6%17,434
5
Levothyroxine-sodium16.5%16,385
6
Ascorbic-acid16.2%16,064
7
Atorvastatin-calcium13.3%13,260
8
Omeprazole13.1%12,996
9
Lisinopril13.0%12,867
10
Cyanocobalamin12.3%12,206
11
Metoprolol11.8%11,691
12
Amlodipine10.5%10,428
13
Metformin10.2%10,146
14
Gabapentin10.1%9,988
15
Folic-acid9.9%9,830

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports fish side effects

58.9% of fish adverse event reports involve female patients and 36.4% involve male patients. The largest age group is adult at 51%. These figures reflect who reports side effects, not underlying risk.

Sex

Female58.9%
Male36.4%
Unknown4.8%

Age group

< 20.4%
2–110.7%
12–170.7%
18–6451.3%
65+46.8%

What is fish used for

Conditions and purposes for which patients were taking fish when the adverse event was reported.

Abdominal DiscomfortAbdominal PainAbdominal Pain UpperAcneAcute Hepatic FailureAcute Respiratory FailureAdjuvant TherapyAdrenal InsufficiencyAdverse Drug ReactionAdverse EventAffective DisorderAlopeciaAmnesiaAnaemiaAnalgesic Therapy

Showing 15 of 554 indications

Fish brand names and reporting trend

Fish is sold under brand names including Smoflipid 20%, Omegaven.

Brand names

Smoflipid 20%100,037
Omegaven78

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking fish with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.