A: Yes there are. Those taking aspirin, warfarin, ibuprofen, heparin, enoxaparin and diclofenac may find that blood clotting is slowed. Taking both krill oil and aspirin or other blood thinning medication at the same time can result in bloodshot eyes and impaired blood clotting. Krill oil should not be taken a few weeks prior to surgery due to its blood thinning action. During this time, foods higher in vitamin K, such as kale, should be added to the diet to encourage proper blood clotting. After surgery and healing, krill oil can be safely added back into your healthy living routine. We recommend speaking with your healthcare provider before taking this, or any other supplement.