Post-orgasmic illness syndrome (POIS) is a rare disease characterized by flu-like symptoms persisting for 2-7 days after ejaculation. POIS has been chiefly attributed to allergic reactions to autologous seminal plasma. However, the exact pathophysiology remains unclear, and there is no effective treatment. We present the case of a 38-year-old man with a 10-year history of recurrent episodes of flu-like symptoms of 1-week duration after ejaculation. The patient was diagnosed with irritating bowel syndrome because of fatigue, myalgia, and lateral abdominal pain. After starting infertility treatment and increasing the frequency of intercourse with his wife, the patient noticed these symptoms after ejaculation. Based on these episodes and symptoms, POIS was suspected. To diagnose POIS, a skin prick test and an intradermal test were performed using his seminal fluid, with the latter yielding a positive result. The patient was diagnosed with POIS, and treatment with antihistamines was continued. Due to its rarity, POIS is often underdiagnosed and underreported; however, the skin test can be a valid diagnostic tool. In this case, the intradermal test result was positive according to the broadly accepted criteria for POIS. Although quality of life is often severely affected in patients with POIS, a lack of a clear understanding of the pathogenesis of POIS prevents early diagnosis. To make diagnoses earlier, it is undoubtedly important to take a detailed medical history and perform skin allergy tests, although the latter requires further validation.
Keywords: antihistamine; intradermal test; post-orgasmic illness syndrome; seminal fluid allergy; skin prick test.
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