Gamma-Linolenic Acid (Evening primrose) γ-linolenic acid is developed as a treatment for atopy in European countries such as England and Germany. The patients who suffer from atopic dermatitis have only half the amount of GLA as healthy people.

Evening primrose (Oenothera erythrosepala or Oenothera odorata), which is familiar in Japan as well, contains γ-linolenic acid (GLA) and is utilized for the treatment of atopic patients in European countries such as England, Germany and France.

Dr. David Horobin, who is a professor at Montreal University in Canada and an authority on research of unsaturated fatty acid, developed an atopic treatment utilizing γ-linolenic acid (GLA). He produced a new curative means, an oral administration of evening primrose seed oil.

Throughout his research covering 25 years, Dr. Horobin found that atopic dermatitis patients had only 50% of the normal amount ofγ-linolenic acid in their blood. Furthermore, it was ascertained that mothers with atopic constitution had 50 % less γ-linolenic acid in their breast milk than healthy mothers did. Therefore, he considered a possibility to supply γ-linolenic acid from plants in nature and took notice of "evening primrose". Then, he accomplished the abstraction of GLA contained in seeds of evening primrose.

The usefulness of γ-linolenic acid on atopic dermatitis is also verified by a clinical demonstration at Bristle University. In this clinical demonstration, it is reported that atopic patients from a slight degree to a medium degree, including of 127 children and 240 adults, experienced relief from symptoms of itching after a dosage of GLA. In addition, 116 out of 179 patients with serious cases of atopic dermatitis also experienced relief from symptoms of itching.