Krill Oil Side Effects and Warnings

Safety Issues

Based on its known constituents, krill oil would be expected to have little to no toxicity. Side effects seen in studies are limited to occasional digestive distress and allergic reactions. The only known potential concerns relate to possible blood-thinning effects: Fish oil is known to decrease blood coagulation, and in one case report it increased the effect of the blood-thinning medication warfarin (Coumadin). ¹ People who are at risk of bleeding complications for any reason should consult a physician before taking krill oil. Maximum safe doses in young children, pregnant or nursing women, or people with severe liver disease have not been established.