γ-Linolenic Acid Ethyl Ester-d5 is the isotope analog of γ-Linolenic Acid Ethyl Ester. γ-Linolenic Acid Ethyl Ester is used in biological studies for neoplasm inhibition of cultured carcinoma cells of human breast. γ-Linolenic Acid Ethyl Ester is also used in the evaluation of hypocholesterolemic activity in rats by comparing it with γ-Linolenic Acid (L467660).