Borage oil is obtained from seeds of the borage plant and is chock full of gamma-linolenic acid (GLA), an essential omega-6 fatty acid. Borage oil is clinically studied for its anti-inflammatory and skin health benefits, and according to PDR Health, borage can be used to treat arthritis, seborrheic dermatitis and eczema. Despite its potential health benefits, borage oil may induce potentially harmful side effects.
Hepatic side effects
Borage oil may contain unsaturated pyrrolizidine alkaloids--compounds containing nitrogen atoms--which are hepatotoxic, or damaging to the liver. Increased and lengthy exposure to borage oil may amplify harm to the liver. To reduce the risk, consumers should take recommended doses of borage oil and should look for products certified free of unsaturated pyrrolizidine alkaloids.
Gastrointestinal side effects
PDR Health warns that borage oil may also cause gastrointestinal side effects, including diarrhea, gas and constipation. Constipation is also a common side effect and may occur upon administration.
In a 2004 edition of the book "Pain Management for Primary Care Clinicians," Dr. David P. Elliott says that gamma linolenic acid obtained from sources such as borage oil may also cause a mild headache and prolonged bleeding when combined with additional herbs or medications with anticoagulant, or blood thinning, properties. PDR Health additionally warns consumers to stop taking borage oil immediately if itching, hives, chest tightness, difficulty breathing, rash, swelling or tingling in the throat or mouth or swelling in the hands or face ensue.