Serious Side Effects of Fish Oil
Some side effects with
fish oil, while occurring infrequently, are potentially serious and should be reported to your healthcare provider. This may indicate that you should stop taking the supplements. These side effects include but are not limited to:
- Any unusual bruising or bleeding (fish oil can increase the risk of bleeding)
- Signs of gastrointestinal bleeding, such as:
- Black, tarry stools
- Bright red blood in the stool
- Vomiting of blood
- Signs of a hemorrhagic stroke (bleeding in the brain), such as:
- Vision or speech changes
- Weakness or numbness in an arm or leg
- Severe headache
- High blood sugar (hyperglycemia), usually in people who already have diabetes
- Signs of an allergic reaction, including:
- An unexplained rash
- Hives
- Itching
- Unexplained swelling
- Wheezing
- Difficulty breathing or swallowing.
Fish oil can also increase
LDL cholesterol ("
bad cholesterol") and may suppress the immune system. Of course, dangerous side effects are possible if a fish oil supplement contains heavy metals or other toxins, some of which may be carcinogenic (may increase the risk of cancer).
If you think you are experiencing a fish oil side effect, please let your healthcare provider know. Also, let your healthcare provider know if you develop something that "just does not seem right." While it may not be a side effect, your healthcare provider will be able to diagnose and treat the problem.