Safety and side effects

When taken in appropriate amounts short term, oral use of evening primrose oil is most likely safe.

Evening primrose oil can cause:

• Upset stomach
• Headache

Don't take evening primrose if you have a bleeding disorder. Oral use of the supplement might increase the risk of bleeding. If you're planning to have surgery, stop taking evening primrose two weeks beforehand.

Also, don't take evening primrose if you have epilepsy or schizophrenia. The supplement might increase your risk of seizures.

Evening primrose oil might increase the risk of pregnancy complications.