Seminal fluid hypersensitivity usually is characterized by postcoital vulvovaginal itching, swelling, redness, with or without systemic signs and symptoms. Efforts to manage this condition have either met with poor patient acceptance or have not been uniformly successful. We describe a 23-year-old atopic woman with documented IgE-mediated local and cutaneous hypersensitivity to SF. Using a controlled, single-blind challenge method, pretreatment with intravaginal 4% cromolyn sodium in a water-based cream completely blocked both local and cutaneous immediate hypersensitivity reactions to SF in this highly sensitive patient. We believe this may represent an alternative and more desirable method of preventive management in such patients.