Background: In most Western countries gamolenic acid is the first-line treatment for women with cyclical mastalgia. Methods: A prospective study was carried out in the breast referral clinic of the Department of Surgery, University of Hong Kung to evaluate the treatment of cyclical mastalgia using gamolenic acid provided in evening primrose oil (Efamast(R), Scotia Pharmaceuticals Ltd, Scotia House, Stirling, Scotland) as a pioneer experience in Asia. in addition, the features of cyclical mastalgia in Oriental women were studied by conducting a survey using anonymous questionnaires. Results: Sixty-six women with disturbing cyclical mastalgia seen by one breast surgeon were followed up with a breast pain diary. Thirty-four women had persistently disturbing mastalgia and were commenced on Efamast(R). Responses were measured at 3 and 6 months according to a standardized protocol. An overall useful response rare of 97% was observed at 6 months. Side-effects were found in 12% but all were insignificant. Conclusions: Efamast(R) may be recommended as a first-line specific treatment for Oriental women with disturbing cyclical mastalgia.