Fish oil is rich in omega-3 fatty acids and may help reduce cardiovascular risk factors in some patients. Chronic, high dose therapy may be associated with a number of complications.

Potential problems with fish oil therapy:

(1) acquired platelet dysfunction, with prolonged bleeding time

(2) elevation of serum LDL or other blood lipids

(3) vitamin A and/or vitamin D intoxication

(4) vitamin E deficiency

(5) gastrointestinal distress



• Heavy metals such as mercury are increased in some seafish, but this has not been reported as a risk in fish oil preparations.


The risk of an adverse effect is greater if:

(1) the person takes high doses of fish oil for long periods

(2) the therapy is not being supervised by someone familiar with fish oil


The acquired platelet dysfunction may become clinically significant if:

(1) the patient is receiving aspirin, coumadin or other therapy affecting the coagulation system

(2) the person has a condition that makes the person hypocoagulable (thrombocytopenia, vitamin K deficiency, liver disease, uremia, other)

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