Postorgasmic illness syndrome
Post orgasmic illness syndrome (POIS) is a condition characterized by debilitating symptoms following orgasm that last for a few hours to several days. The phenomenon was first described in 2002.
The sufferer experiences mental symptoms, physical symptoms, or both. Common mental symptoms include cognitive dysfunction, intense discomfort, irritability, anxiety, craving for relief, susceptibility to nervous system stresses (e.g. common cold), depressed mood, and difficulty communicating, remembering words, reading and retaining information, concentrating, and socialising. Physical symptoms include severe fatigue, mild to severe headache, and flu-like and allergy-like symptoms, such as sneezing, itchy eyes, nasal irritation, and muscle pain. Affected individuals may also experience intense warmth.
Waldinger says this condition is prone to being erroneously ascribed to psychological factors or hypochondria. In a 2010 British Medical Journal case study, Dexter links a form of coital headache with POIS, and references a science forum in which thousands of sufferers (a number which is rapidly growing) have detailed their condition. Dexter's patient was found to have low progesterone.
POIS patients are beginning to be treated using hyposensitation techniques for semen allergies.
Most recently, in early 2011, Professor Waldinger and collaborators further characterized POIS, proposed a specific immunological mechanism, and empirically supported their hypothesis on 45 Dutch Caucasian males. This study concluded that both Type-1 and Type-4 allergy to male's own semen contribute to symptoms of the illness.
Dexter speculates that POIS could be caused by a lack of progesterone, a powerful neurosteroid, or a defect in neurosteroid precursor synthesis. In the latter case, the same treatment may not be effective for different sufferers. Different sufferers may have different missing precursors, ultimately leading to a deficiency of the same particular neurosteroid, causing similar symptoms.
An array of more subtle, lingering symptoms after orgasm, which would not constitute POIS, may contribute to habituation between mates. They may show up as restlessness, irritability, increased sexual frustration, apathy, sluggishness, neediness, dissatisfaction with a mate, or weepiness  over the days or weeks after intense sexual stimulation. Such phenomena may be part of human mating physiology itself. Habituation to a mate can drive the search for novel mates (the Coolidge effect). Possible neurochemical mechanisms behind such effects are discussed in "The Passion Cycle."
One researcher suggests that the symptoms may be produced by an autoimmune reaction against any of various hormones or other substances secreted during and after sex. Another suggests that chemical imbalances in the brain may cause the symptoms.
It is difficult to demonstrate a causal relationship based on patient reports.
POIS could affect between 0.25% and 1% of the population.
In the United States of America, POIS is recognized as a rare disorder by the National Institutes for Health (NIH), Office of Rare Diseases Research. It is also listed in the organizational database of the National Organization for Rare Disorders (NORD).
See also 
|Look up POIS in Wiktionary, the free dictionary.|
- Waldinger MD, Meinardi M, Zwinderman A, Schweitzer, D. (April 2011). Postorgasmic Illness Syndrome (POIS) in 45 Dutch Caucasian Males: Clinical Characteristics and Evidence for an Immunogenic Pathogenesis (Part 1). The Journal of Sexual Medicine. doi:10.1111/j.1743-6109.2010.02166.x.
- Waldinger MD, Schweitzer DH (2002). "Postorgasmic illness syndrome: two cases". J Sex Marital Ther 28 (3): 251–5. doi:10.1080/009262302760328280. PMID 11995603.
- Dexter S (2010). "Benign coital headache relieved by partner’s pregnancies with implications for future treatment". British Medical Journal.
- Richard Balon, R. Taylor Segraves (2005). Handbook of sexual dysfunction. Informa Health Care. ISBN 978-0-8247-5826-4. Retrieved 2009-05-11.
- "The Naked Scientists". 2010.
- Waldinger MD, Meinardi M, Zwinderman A, Schweitzer, D. (April 2011). Hyposensitization Therapy with Autologous Semen in Two Dutch Caucasian Males: Beneficial Effects in Postorgasmic Illness Syndrome (POIS; Part 2). The Journal of Sexual Medicine. doi:10.1111/j.1743-6109.2010.02167.x.
- Friedman, Richard A. (19 January 2009). "In the Brain, if Not the Mind". The New York Times. Retrieved 12 May 2009.
- Burri AV, Spector TD. (June 2011). "An epidemiological survey of post-coital psychological symptoms in a UK population sample of female twins". Twin Res Hum Genet.
- Robinson and Wilson (30 August 2009). "The Passion Cycle". Psychology Today Blogs.
- "Dutch Doctor Identifies Post-Orgasmic Syndrome". Amsterdam. Reuters. 12 April 2002.
- Berger, Joanne M. (1 June 2002). "Allergic to sex? (Indications)". International Medical News Group.
- Rasmussen BK, Olesen J (1992). "Symptomatic and nonsymptomatic headaches in the general population.". Neurology 42 (6): 1225–31. PMID 1603351.
- Semen allergy suspected in rare post-orgasm illness (Reuters, January 17, 2011)