This article explains what a phobia is and details which ones are the least common.

Specific Phobias

According to the National Institute of Mental Health (NIMH), specific phobias affect approximately 12.5% of adults in the United States at some point during their lives, making them among the most common mental health conditions. In order to be diagnosed with a specific phobia, a person must:

Experience severe fear or anxiety about the object or situationHave an immediate fear responseThe fear must be excessive and out of proportion to the actual riskSymptoms must last six months or longerFear must cause distress and impairments in functioningThese symptoms must not be better explained by another mental health condition

Specific phobias typically fall into one of four different categories. These categories are fears related to animals, the natural environment, medical issues or treatments, and specific situations. While there are statistics about the general prevalence of phobias, there is a lack of information about the occurrence of each individual type of phobia. This is because virtually any object or situation can become a source of fear.  The most common phobias tend to be the most studied. In many cases, rare phobias are named through the formation of “nonce” words, which are words coined for single use. When such phobias are identified, they are often named by taking the Greek word for the feared object and adding the “phobia” suffix.  There may be any number of specific phobias, including some of the following rarest phobias that researchers have identified, described, and studied. Because these phobias tend to be rare, there is little research on their symptoms, origins, and treatments. In many cases, the only available information is single case studies.

Alektrophobia

Specific phobias are often focused on a fear of a certain type of animal. Common animal fears typically involve creatures such as snakes, dogs, or insects. In such cases, the cause of the phobia might be rooted in a past negative experience, such as being bitten by a dog, or evolutionary influences, such as fearing snakes or spiders because they might be poisonous. People can also fear an animal that may not seem to pose a serious threat. In one case report, researchers reported an instance of an 18-year-old woman with a severe fear of chickens and hens, a phobia known as alektorophobia. While uncommon, the condition may be related to the more common ornithophobia, which involves the fear of birds. As with other more common phobias, this case was connected to a terrifying childhood experience with a chicken, which resulted in a lasting fear that led to anticipatory anxiety and complete avoidance of any situation where the young woman might encounter a chicken. While rare, the phobia was successfully treated by utilizing exposure therapy, a type of cognitive-behavioral therapy involving progressive exposure to the source of the fear.

Gerascophobia 

Gerascophobia involves the fear of aging or growing up. This fear can lead to severe emotional distress and potentially dangerous behaviors, such as food restriction and other attempts to keep the body from maturing. In one case report described by researchers, a 14-year-old boy with the condition restricted his food intake to avoid the nutrients needed for growth, walked with a hunched posture to disguise his height, and spoke in a softer, higher-pitched voice to sound and look younger. In this case, other symptoms of the condition included experiencing extreme anxiety, depression, and distress at signs of aging. Those symptoms were accompanied by a severe fear of adult responsibilities, including becoming independent, taking on financial obligations, and finding a partner.

Ambulophobia 

Ambulophobia involves a fear of walking. The condition can lead to serious impairments in a person’s life and ability to function. Fear of walking tends to be much more common in older adults than in children and younger people. This is due to risk factors such as balance problems, dizziness, joint issues, osteoporosis, visual impairments, and side effects of medications that can increase the risk of serious falls and injuries. While rare in younger people, it is more prevalent in older age groups. In one study of 379 people in long-term care facilities, researchers found that 30.1% had symptoms of ambulophobia. Among these participants, women and those over 70 were most likely to be affected. Health conditions that can increase the likelihood of falling are a significant risk factor for this rare phobia. Conditions such as depression, postural hypotension, Parkinson’s disease, and a history of falling were all found to be risk factors for ambulophobia.

Emetophobia 

Emetophobia is a specific phobia involving intense and persistent fear of vomiting. While research suggests that a mild fear of vomiting is more common, affecting 3.1% to 8.8% of people, emetophobia is considered quite rare, affecting approximately 0.1% of the population. Symptoms of the condition can include anxiety that causes feelings of nausea and stomach upset. These distressing physical symptoms worsen the anxiety about vomiting, leading to a self-perpetuating cycle. While emetophobia is considered rare in and of itself, milder forms of the fear of vomiting can still lead to potential problems. Some people may develop additional phobias such as cibophobia, which involves the fear of food, particularly those that might lead to stomach upset or illness. 

Arachibutyrophobia 

Arachibutyrophobia is a rare phobia that involves a fear of getting peanut butter stuck to the roof of your mouth. This fear may have a number of causes, including a more general fear of choking or traumatic experiences involving a peanut allergy. People who have experienced anaphylaxis as a result of an allergic reaction may experience lingering feelings of stress and anxiety after the event. In some cases, they may also develop symptoms of post-traumatic stress disorder (PTSD).

Spectrophobia 

Spectrophobia is a rare phobia that causes people to experience fear in response to mirrors or what is reflected in a mirror. They might fear seeing themselves or other people or objects reflected in a mirror surface. Research suggests that people with depression or schizophrenia are more likely to perceive distortions when looking at their reflection in a mirror. As a result of this fear, people may avoid any situation where they might encounter a mirror. This can create significant disruptions in an individual’s life, making it difficult to enter different social settings or even leave the house. 

Decidophobia 

While many people struggle with anxiety about making decisions, some people experience fear so severe that it constitutes a specific phobia. Decidophobia is an intense and paralyzing fear about making any decision, from small everyday choices to larger life decisions. Symptoms of this phobia include putting off decisions out of fear of making the wrong choice, feeling panic when making decisions, and a dependence on others to make choices.

Hippopotomonstrosesquipedaliophobia

Hippopotomonstrosesquipedaliophobia, also known as sesquipedaliophobia, this intimidatingly-long word is the name of a rare phobia that involves a fear of…intimidatingly-long words. The exact nature of the fear can vary from one person to the next. Some people might fear long words that are difficult to spell, while others might fear words that are difficult to say aloud.  In either case, encountering long words can lead to feelings of anxiety and panic. In some cases, people with specific phobias may experience panic attacks when they encounter the source of their fear.

Chiclephobia 

Chiclephobia is a rare phobia that involves a fear of chewing gum. Symptoms of anxiety and panic may happen when people think about chewing gum, but it can also involve seeing other people chewing gum or seeing previously-chewed gum.  The exact causes of this fear are not fully understood, but like other phobias, it might be caused by a previous negative experience. People might be more likely to develop a phobia if they have a family member who has a phobia, anxiety disorder, or other mental health condition.

Phobophobia 

One of the most uncommon phobias involves a severe fear of phobias. People who have other anxiety disorders or other types of specific phobias may be at a higher risk of developing this type of phobia.  Symptoms associated with phobophobia include symptoms common to other specific phobias. This includes physical feelings of fear such as chills, sweating, and rapid heartbeat. It may also include avoidance of any situation that might produce feelings of fear or anxiety.

A Word From Verywell

While these represent some of the rarest phobias, it is important to remember that specific phobias tend to be highly treatable no matter how common or rare they might be. Research suggests that psychotherapy, particularly cognitive-behavioral therapy (CBT) and exposure therapy, produces positive results for treating different types of specific phobias. Technology-assisted treatment, such as virtual exposure therapy, can also be effective.