Can omega-3 be dangerous?

In excess: Fish oil does have some properties as a blood thinner, and may, in the extreme, contribute to bruising or affect a patient in surgery. Omega-3 supplements are usually restricted during the 10-14 days before major elective surgery, (along with Aspirin and anti-inflammatories).

Fish oil intox: A good review... http://www.livestrong.com/article/306969-the-side-effects-toxicity-of-fish-oil/ according to medlineplus... Because fish oil pills are concentrated they can cause indigestion, belching, bad breath, heartburn, nausea and stomach aches, this side effect may be reduced by taking it with meals. Vit e intoxication & lower blood pressure, & lower immune response are possibilities.