An overview of krill oil, such as the one available from WebMD, describes its source, uses and side effects. Krill oil is harvested from tiny shrimp-like creatures and is similar to fish oil. It contains fatty acids that, when taken in capsule form, are believed to be beneficial for decreasing swelling, lowering cholesterol and rendering blood platelets less sticky, which makes platelets less likely to form clots.
Krill oil is taken to help prevent heart disease, high blood levels of certain fats called triglycerides, high cholesterol, high blood pressure, stroke, cancer, osteoarthritis, depression, premenstrual syndrome and painful menstrual periods. WebMD states that more evidence is needed to support these claims, but krill oil seems to be harmless in adults when taken for three months or less. Krill oil supplements may cause side effects similar to fish oil, including bad breath, heartburn, a fishy taste in the mouth, nausea, upset stomach and loose stools. If krill oil supplements are taken in conjunction with other medications that decrease blood clotting, such as aspirin, ibuprofen or warfarin, the combination may increase the chances of bruising and bleeding. Patients who plan to undergo surgery should avoid taking krill oil supplements as they may inhibit clotting and increase post-surgical bleeding.