Allergy to human seminal plasma (HSP) is rare. It presents with a variety of symptoms, ranging from localized changes to generalized reactions or even anaphylactic shock. Symptoms typically start within minutes to one hour after exposure. Diagnosis is based on history, evidence of specific IgE antibodies and skin prick testing (SPT). A 25-year-old Caucasian woman presented with eyelid swelling, generalized urticaria and dyspnea immediately after unprotected coitus with her partner. No symptoms occurred when barrier contraception was used. SPTand IgE testing (ImmunoCAP) demonstrated sensitization to HSP and dog dander. The patient's self-designed desensitization protocol, consisting of H1 blocker premedication followed by unprotected sexual intercourse, ameliorated her systemic reactions gradually and reduced the frequency of emergency hospital visits. She had a known allergy to male but not female dogs, and was highly sensitized to dog allergen Can f 5, a protein homologous to human prostate-specific antigen (PSA), suggesting a possible link to her HSP allergy.