Gamma-Linolenic Acid
Gamma-linolenic acid (GLA) is an omega-6 fatty acid found in evening primrose, borage and blackcurrant seed oils.
Safety depends partly on the source oil
Evening primrose oil commonly causes stomach symptoms such as nausea, abdominal pain or diarrhea. NCCIH recommends checking its use with a health professional when taking medicines. Evidence in pregnancy and breastfeeding is inconclusive, and less is known about use in children. 1
The Cochrane eczema review also highlights a possible increase in bleeding when evening primrose oil is combined with warfarin. 2
Borage requires an additional quality check
DGRh warns that borage can contain pyrrolizidine alkaloids, substances that can damage the liver and genetic material. Its warning against regular use of leaves and flowers should not be confused with evidence about a purified seed-oil product. It does not recommend borage-oil preparations as adjunctive rheumatic treatment. 3
For information, not individual medical advice. Ingredient studies do not establish the effectiveness of these products.