Boanthropy is a rare psychological condition in which a person believes they are a cow or an ox. It falls under the broader category of zoanthropy, a type of delusion where someone becomes convinced they have transformed into an animal. People experiencing boanthropy may walk on all fours, eat grass, and moo instead of speaking. It is not a standalone diagnosis but rather a symptom observed across several psychiatric conditions.
How Boanthropy Looks in Practice
The central feature of boanthropy is a fixed belief that one is bovine. This isn’t a metaphor or a game. The person genuinely perceives themselves as a cow or ox and begins behaving accordingly. They may drop to their hands and knees to walk on four limbs, refuse to eat human food in favor of grass or raw vegetation, and replace speech with animal vocalizations.
In severe cases, this delusion can consume a person’s entire life. They may abandon their job, home, and relationships to live as their perceived animal self. Hallucinations often accompany the delusion, reinforcing the belief and making it extremely difficult for the person to recognize that anything is wrong. Early warning signs can include intrusive thoughts about being bovine, hallucinations, and a growing internal urge to act like a cow.
Boanthropy and Other Animal Delusions
Boanthropy is one specific form of zoanthropy. The most well-known version is clinical lycanthropy, where a person believes they are turning into a wolf. But the animal involved in these delusions varies widely. A 2021 systematic review published in Frontiers in Psychiatry cataloged cases involving dogs, cats, snakes, pigs, wild boars, frogs, bees, gerbils, tigers, sharks, and crocodiles, among others. A cow transformation delusion was identified in the Middle East.
The type of animal often reflects a person’s cultural environment and personal experiences. In one documented case, a 43-year-old man with bipolar disorder became convinced he had transformed into a wild boar after real contact with those animals during an episode of alcohol intoxication. Cat transformation delusions, called ailuranthropy, have been reported in people with bipolar disorder and treatment-resistant psychosis. One man believed he was a cat for 13 uninterrupted years, living with cats and adopting their behaviors entirely.
What all these conditions share is the core delusion of species transformation. The specific animal changes, but the underlying psychiatric mechanism is the same.
What Causes It
Boanthropy is not a disorder on its own. It is a delusional symptom that appears in the context of other neuropsychiatric conditions. The most common underlying diagnoses are schizophrenia-spectrum disorders and severe psychotic depression. But zoanthropic delusions have also been documented in people experiencing drug intoxication or withdrawal, traumatic brain injury, dementia, delirium, seizures, cerebrovascular disease, and in rare cases, obsessive-compulsive and related disorders.
One case report described a 25-year-old man who believed he had transformed into a buffalo. His delusion developed alongside obsessive-compulsive features, which is an unusual presentation. This highlights that zoanthropic delusions can surface in unexpected psychiatric contexts, not just the conditions most commonly associated with psychosis.
Cultural context also plays a role. Beliefs about human-animal transformation exist in many societies, from werewolf folklore in Europe and Haiti to possession rituals in various traditional practices. These cultural frameworks can shape how a psychotic delusion manifests, steering its content toward specific animals that hold symbolic weight in the person’s background.
The Nebuchadnezzar Account
The most frequently cited historical example of boanthropy comes from the Bible. In the Book of Daniel, chapter 4, King Nebuchadnezzar of the Neo-Babylonian Empire (who ruled from 605 BC to 562 BC) is described as being “driven from men” and eating “grass as oxen.” According to the biblical account, the king lost his sanity as divine punishment for boasting about his achievements and lived like an animal for seven years before his reason returned.
Whether Nebuchadnezzar’s condition was truly boanthropy in the clinical sense is impossible to verify from a religious text written centuries after the fact. But the account remains the most famous reference point for the condition, and it illustrates that delusions of animal transformation have been recognized for thousands of years.
How Boanthropy Is Treated
Because boanthropy is a symptom of an underlying psychiatric condition rather than a standalone illness, treatment focuses on the root cause. Antipsychotic medications are the primary approach and tend to work relatively well, particularly when the delusion arises from schizophrenia-spectrum disorders or psychotic depression. Electroconvulsive therapy has also shown effectiveness in some cases, along with psychological interventions.
The prognosis depends heavily on the underlying condition. In some documented cases of zoanthropy tied to bipolar disorder, the delusion resolved completely with treatment. In others, particularly those involving chronic, treatment-resistant psychosis, the belief persisted for years. The earlier someone receives psychiatric care after the onset of delusional symptoms, the better the chances of a meaningful recovery.
Historically, approaches were more creative. The Persian physician Ibn Sina (known in the West as Avicenna, active around 1000 AD) reportedly treated a prince suffering from boanthropy who believed he was a cow and refused to eat. Ibn Sina’s intervention is one of the earliest recorded attempts to address the condition through a deliberate therapeutic strategy rather than attributing it to supernatural forces.