Is shrinking penis syndrome a delusion or a real thing?

In the medical culture of the Bugis and Makassar peoples in Indonesia the word koroq means that the penis is actually shrinking, or retracting, but the Dutch in the 19th-century East Indies did not believe it was real. shutterstock

The author has presented his paper on koro and traditional healing practices in Indonesia at the History of Medicine in Southeast Asia Symposium, 27-30 June, 2018 at the Indonesian Academy of Sciences.


In the 19th century, the Dutch, who ruled over the then Netherlands East Indies (now Indonesia), encountered curious phenomena known as amok, latah and koro.

They were intrigued and puzzled, and proposed that these were psychiatric syndromes specific to the local culture. Amok is understood as an uncontrolled outburst of anger and latah as an exaggerated startle reflex, with Indonesian cultures modifying and interpreting these phenomena in specific local ways.

Koro is the least known of these three syndromes, being largely localised to South Sulawesi. In the medical culture of the Bugis and Makassar peoples, the word koroq means that the penis is actually shrinking, or retracting, but the Dutch did not believe this was real.

While they knew the penis was retractable on exposure to cold, they did not accept that other forms of retraction were possible. They adopted the word koroq, leaving out the glottal stop at the end of the word, and defined it as a delusional condition in which the patient mistakenly believes his penis is shrinking. This became the prevailing view in the international literature and appears in major psychiatric texts around the world.

The International Classification of Diseases (ICD), maintained by the World Health Organisation, is based on universal human biology rather than culture, so these peculiar culturally localised syndromes are listed in an appendix outside the main classification.


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Delusion or state of anxiety?

In 1985, American psychiatrist Ronald Simons proposed that retraction of the penis in koro attacks was a protective reflex in fight-or-flight situations. A slight penis retraction, which normally occurs in anxiety states, can turn into a major panic attack with an extreme degree of retraction, due to a positive feedback loop – retraction causes anxiety, then anxiety causes more retraction, and so on.

Penis retraction as a protective reflex keeps the penis safe from injury in fight-or-flight situations in animals. In Simons’ model this reflex is partially preserved in humans.

Simons’ theory also offers an explanation of koro in terms of universal human biology rather than in culture. This proposal has not been widely accepted, however. The definition of koro as a kind of delusional disorder is still entrenched in the international literature.

In Indonesia, koro is treated by traditional healers, called dukun, who are often semi-literate villagers.

The dukuns certainly do not read the international medical literature and simply follow the healing methods of local oral traditions. Evidence from the practice of these healers fits better within Simons’ panic attack model than with the concept of a delusional disorder.

When a patient arrives in a state of panic saying his penis is shrinking, the dukun takes the complaint at face value. He administers his treatments, thus relieving the panic and allowing the retracted penis to return to its normal condition.

If koro is understood as a panic attack, this recovery is not surprising since panic attacks normally escalate to a peak and then rapidly subside, so the dukun is simply facilitating a natural resolution.

Where else in Indonesia?

These retraction panic syndromes occur in several regions in Indonesia. The first records are from South Sulawesi where koro was described in 1859. Only in the last few decades has significant evidence emerged in other regions.

In west and central Flores the retraction panic syndrome is known as ru’u pota, “shrinking magic”. The local newspaper Flores Post reported an epidemic of hundreds of cases in Ende from October 5 to 7, 1999.

In eastern Sumba it is known as hei lulu, “everything goes up”. In the Belu district of Timor it is known as lulik oan subaran, “the little sacred thing is hiding itself”. Reports of these conditions appear in local newspapers or the reports of local anthropologists, but never in medical journals.

Story of a koro healer

Because of the uncertainty surrounding Simons’ theory, when I heard in 2002 of a Sumbanese dukun on the outskirts of Waingapu, who was well known for curing koro, I decided to pay him a visit.

Umbu Hina Panjarra was a pig farmer and a big fan of Megawati, the previous president of Indonesia, and he was keen to talk. He told us that not just ordinary villagers but also important government officials would be driven urgently to his humble earthen-floored house, often with a string tied around their penis to prevent it disappearing.

Hina Panjarra of Waingapu, a dukun and fan of former president Megawati Soekarnoputri, in his home with his special massage oil. David Peter Mitchell, Author provided

Hina would give a vigorous massage, working upwards from the calf and thighs, and downwards from the abdominal muscles, as if driving some bodily energy towards the shrunken penis. It was essential to work vigorously, he explained, and apply painful levels of pressure.

His style was that of an enthusiastic showman. He liked to have his patient stripped naked as he worked so that the improving state of the penis could be seen, and the drama of removing the string was a sign that both healer and patient were now confident the crisis was passing.

This was fascinating material. But it is anecdotal and does not prove Simons’ thesis.

Hina did not have any measurements or photographs or records of any kind. His language was that of a charismatic healer rather than the language of an objective, carefully self-critical observer.

But his story does suggest that there is a retraction reflex worthy of proper physiological study.

I had been easily able to find Hina Panjarra in Sumba because I had been the head of the government health services in West Sumba in 1968-69, but I was just a visitor in 2002 and no longer in a position to arrange for collecting observational evidence on Hina’s patients. I was persuaded, however, that it was worth collecting more information on this topic.

In Ende, Flores dukun Jeremias Ima, a ru u pota expert, here is treating a headache. David Peter Mitchell, Author provided

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New evidence

Recently, new evidence has emerged from doctors in Cairo, Egypt, using botox injections in men who are embarrassed by a retracting penis. They have published measurements of the degree of retraction and improvements achieved by botox.

Following local leads, I have visited Ende and later Makassar, and located local healers in both places, treating the local ru’u pota and koroq syndromes.

Although cultural beliefs differ from one place to the next, as do the styles and curing methods of the dukuns, all three of the healers I have spoken to insisted on two things: that retraction was real, and that as long as the patients made it safely to the dukun’s home, they could all be cured and the penis restored to its normal condition.

Although koro was discovered in Indonesia, recent international publications on koro come from India, Africa and many countries around the world, but none originate in Indonesia.

Perhaps the time has come for Indonesian medical anthropologists and medical researchers to reclaim the subject of koro, taking advantage of the continuing practice of dukuns in this field.

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