Most phobias are classified into three categories and, according to the "Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition" (DSM-V), such phobias are considered to be sub-types of anxiety disorder. The categories are:

1. Specific phobias: Fear of particular objects or social situations that immediately results in anxiety and can sometimes lead to panic attacks. Specific phobia may be further subdivided into five categories: animal type, natural environment type, situational type, blood-injection-injury type, and other.

2. Agoraphobia: a generalized fear of leaving home or a small familiar 'safe' area, and of possible panic attacks that might follow. It may also be caused by various specific phobias such as fear of open spaces, social embarrassment (social agoraphobia), fear of contamination (fear of germs, possibly complicated by obsessive-compulsive disorder) or PTSD (post traumatic stress disorder) related to a trauma that occurred out of doors.

3. Social phobia, also known as social anxiety disorder, is when the situation is feared as the person is worried about others judging them.

Phobias vary in severity among individuals. Some individuals can simply avoid the subject of their fear and suffer relatively mild anxiety over that fear. Others suffer full-fledged panic attacks with all the associated disabling symptoms. Most individuals understand that they are suffering from an irrational fear, but are powerless to override their panic reaction. These individuals often report dizziness, loss of bladder or bowel control, tachypnea, feelings of pain, and shortness of breath.

A specific phobia is any kind of anxiety disorder that amounts to an unreasonable or irrational fear related to exposure to specific objects or situations. As a result, the affected person tends to avoid contact with the objects or situations and, in severe cases, any mention or depiction of them. The fear can, in fact, be disabling to their daily lives.

The fear or anxiety may be triggered both by the presence and the anticipation of the specific object or situation. A person who encounters that of which they are phobic will often show signs of fear or express discomfort. In some cases, it can result in a panic attack. In most adults, the person may logically know the fear is unreasonable but still find it difficult to control the anxiety. Thus, this condition may significantly impair the person's functioning and even physical health.

Specific phobia affects up to 12% of people at some point in their life.

A specific phobia is a marked and persistent fear of an object or situation which brings about an excessive or unreasonable fear when in the presence of, or anticipating, a specific object; the specific phobias may also include concerns with losing control, panicking, and fainting which is the direct result of an encounter with the phobia. Specific phobias are defined in relation to objects or situations whereas social phobias emphasize social fear and the evaluations that might accompany them.

The DSM breaks specific phobias into five subtypes: animal, natural environment, blood-injection-injury, situation and other. In children, blood-injection-injury phobia and phobias involving animals, natural environment (darkness) usually develop between the ages of 7 and 9, and these are reflective of normal development. Additionally, specific phobias are most prevalent in children between ages 10 and 13.

Emetophobia is a phobia that causes overwhelming, intense anxiety pertaining to vomiting. This specific phobia can also include subcategories of what causes the anxiety, including a fear of vomiting in public, a fear of seeing vomit, a fear of watching the action of vomiting or fear of being nauseated. It is common for emetophobics to be underweight, or even anorexic, due to strict diets and restrictions they make for themselves. The thought of someone possibly vomiting can cause the phobic person to engage in extreme behaviors to escape the perceived (and sometimes very real) threat of that particular situation, in which the phobic person will go to great lengths to avoid even potential situations that could even be perceived as "threatening".

Emetophobia is clinically considered an "elusive predicament" because limited research has been done pertaining to it. The fear of vomiting receives little attention compared with other irrational fears. Emetophobia is not limited by age or maturity level. There are cases of emetophobia present in childhood and adolescence, as well as adulthood.

The event of vomiting may scare away anyone with this peculiar phobia. Some may fear someone throwing up while another may fear themselves throwing up. Some may have both.

Some may have anxiety which makes them feel like they will throw up when it actually might not. People with Emetophobia usually suffer from anxiety, they often scream or cry when someone or something has been sick.

Individuals with scopophobia generally exhibit symptoms in social situations when attention is brought upon them like public speaking. Several other triggers exist to cause social anxiety. Some examples include: Being introduced to new people, being teased and/or criticized, embarrassing easily, and even answering a cell phone call in public.

Often scopophobia will result in symptoms common with other anxiety disorders. The symptoms of scopophobia include an irrational feelings of panic, feelings of terror, feelings of dread, rapid heartbeat, shortness of breath, nausea, dry mouth, trembling, anxiety and avoidance. Other symptoms related to scopophobia may be hyperventilation, muscle tension, dizziness, uncontrollable shaking or trembling, excessive eye watering and redness of the eyes.

Phobophobia is the fear of phobia(s) and, more specifically, of the internal sensations associated with that phobia and anxiety, which binds it closely to other anxiety disorders, especially with generalized anxiety disorders (free floating fears) and panic attacks. It is a condition in which anxiety disorders are maintained in an extended way, which combined with the psychological fear generated by phobophobia of encountering the feared phobia would ultimately lead to the intensifying of the effects of the feared phobia that the patient might have developed, such as agoraphobia, and specially with it, and making them susceptible to having an extreme fear of panicking. Phobophobia comes in between the stress the patient might be experiencing and the phobia that the patient has developed as well as the effects on his life, or in other words, it is a bridge between anxiety/panic the patient might be experiencing and the type of phobia he/she fears, creating an intense and extreme predisposition to the feared phobia. Nevertheless, phobophobia is not necessarily developed as part of other phobias, but can be an important factor for maintaining them.

Phobophobia differentiates itself from other kind of phobias by the fact that there is no environmental stimulus per se, but rather internal dreadful sensations similar to psychological symptoms of panic attacks. The psychological state of the mind creates an anxious response that has itself a conditioned stimuli leading to further anxiety, resulting in a vicious cycle. Phobophobia is a fear experienced before actually experiencing the fear of the feared phobias its somatic sensations that precede it, which is preceded by generalized anxiety disorders and can generate panic attacks. Like all the phobias, the patients avoids the feared phobia in order to avoid the fear of it.

Main features of diagnostic criteria for specific phobia in the DSM-IV-TR:

- Marked and persistent fear that is excessive or unreasonable, cued by the presence or anticipation of a specific object or situation (e.g., flying, heights, animals, receiving an injection, seeing blood).

- Exposure to the phobic stimulus almost invariably provokes an immediate anxiety response, which may take the form of a situationally bound or situationally predisposed panic attack. In children, the anxiety may be expressed by crying, tantrums, freezing, or clinging.

- The person recognizes that the fear is excessive or unreasonable. In children, this feature may be absent.

- The phobic situation(s) is avoided or else is endured with intense anxiety or distress.

Specific Phobia – DSM 5 Criteria

- Fear or anxiety about a specific object or situation (In children fear/anxiety can be expressed by crying, tantrums, freezing, or clinging)

- The phobic object or situation almost always provokes immediate fear or anxiety

- The phobic object or situation is avoided or endured with intense fear or anxiety

- The fear or anxiety is out of proportion to the actual danger posed by the specific object or situation and to the sociocultural context

- The fear, anxiety, or avoidance is persistent, typically lasting for 6 months or more

- The fear, anxiety, or avoidance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning

- The disturbance is not better explained by symptoms of another mental disorder, including fear, anxiety, and avoidance of situations associated with panic-like symptoms or other incapacitating symptoms; objects or situations related to obsessions; reminders of traumatic events; separation from home or attachment figures; or social situations

People with a fear of driving may experience trembling, sweating, accelerated pulse, loss of sense of reality, and thoughts of losing control while driving, even in situations that are reasonably safe. This fear will cause many to avoid driving, create excuses to not drive, or even refuse to get a driver's license for years.

Those with associated post-traumatic stress disorder may experience intrusive thoughts or dreams of the original accident—both when driving and not—lack of emotional responsiveness and irritability.

The root word for emetophobia is "emesis", from the Greek word "emein" which means "an act or instance of vomiting" with "-phobia” meaning "an exaggerated usually inexplicable fear of a particular object, class of objects, or situation."

People with emetophobia frequently report a vomit related traumatic event, such as a long bout of stomach flu, accidentally vomiting in public, or having to witness someone else vomit, as the start of the emetophobia. They may also be afraid of hearing that someone is feeling like vomiting or that someone has vomited, usually in conjunction with the fears of seeing someone vomit or seeing vomit.

Phobophobia is mainly linked with internal predispositions. It is developed by the unconscious mind which is linked to an event in which phobia was experienced with emotional trauma and stress, which are closely linked to anxiety disorders and by forgetting and recalling the initiating trauma. Phobophobia might develop from other phobias, in which the intense anxiety and panic caused by the phobia might lead to fearing the phobia itself, which triggers phobophobia before actually experiencing the other phobia. The extreme fear towards the other phobia can lead the patient to believe that their condition may develop into something worse, intensifying the effects of the other phobia by fearing it. Also, phobophobia can be developed when anxiety disorders are not treated, creating an extreme predisposition to other phobias. The development of phobophobia can also be attributed to characteristics of the patient itself, such as phylogenetic influence, the prepotency of certain stimuli, individual genetic inheritance, age incidence, sex incidence, personality background, cultural influence inside and outside the family, physiological variables and biochemical factors.

Phobophobia shares the symptoms of many other anxiety disorders, more specifically panic attacks and generalized anxiety disorder:

1. Dizziness

2. Heart pounding

3. An excess of perspiration

4. Slight paresthesia

5. Tension

6. Hyperventilation

7. Angst

8. Faintness

9. Avoidance

The "DSM-IV-TR" provides the following criteria for the diagnosis of a specific phobia:

The book "Phobias" defines a panic attack as "a sudden terror lasting at least a few minutes with typical manifestations of intense fear". These manifestations may include palpitations, sweating, trembling, difficulty breathing, the urge to escape, faintness or dizziness, dry mouth, nausea and/or several other symptoms. As with other specific phobias, patients suffering from cynophobia may display a wide range of these reactions when confronted with a live dog or even when thinking about or presented with an image (static or filmed) of a dog. Furthermore, classic avoidance behavior is also common and may include staying away from areas where dogs might be (i.e., a park), crossing the street to avoid a dog, or avoiding the homes of friends and/or family who own a dog.

Driving phobia, also called vehophobia or a fear of driving, can be severe enough to be considered an intense, persistent fear or phobia. It is often great enough that people will avoid driving at all costs, and instead find someone to drive them or use public transportation, regardless of how inconvenient or expensive.

A fear of driving may escalate to a phobia during difficult driving situations, such as freeway driving or congested traffic.

The symptoms of autophobia vary by case. However, there are some symptoms that a multitude of people with this disease suffer from. An intense amount of apprehension and anxiety when you are alone or think about situations where you would be secluded is one of the most common indications that a person is autophobic. People with this disorder also commonly believe that there is an impending disaster waiting to occur whenever they are left alone. For this reason, autophobes go to extreme lengths to avoid being in isolation. However, people with this disease often do not need to be in "physical" isolation to feel abandoned. Autophobes will often be in a crowded area or group of people and feel as though they are completely secluded.

There has also been some connection to autophobia being diagnosed in people who also suffer from borderline personality disorders.

Below is a list of other symptoms that are sometimes associated with autophobia:

- Mental symptoms:

- Fear of fainting

- A disability to concentrate on anything other than the disease

- Fear of losing your mind

- Failure to think clearly

- Emotional symptoms:

- Stress over up-coming times and places where you may be alone

- Fear of being secluded

- Physical symptoms:

- Lightheadedness, dizziness

- Sweating

- Shaking

- Nausea

- Cold and hot flashes

- Numbness or tingling feelings

- Dry mouth

- Increased heart rate

A variety of symptoms can be seen in someone suffering from telephone phobia, many of which are shared with anxiety. These symptoms may include nervous stomach, sweaty palms, rapid heartbeat, shortness of breath, nausea, dry mouth and trembling. The sufferer may experience feelings of panic, terror and dread. Resulting panic attacks can include hyperventilation and stress. These negative and agitating symptoms can be produced by both the thought of making and receiving calls and the action of doing so.

Blood phobia (also AE: hemophobia or BE: haemophobia) is the extreme and irrational fear of blood, a type of specific phobia. Severe cases of this fear can cause physical reactions that are uncommon in most other fears, specifically vasovagal syncope (fainting). Similar reactions can also occur with trypanophobia and traumatophobia. For this reason, these phobias are categorized as "blood-injection-injury phobia" by the DSM-IV. Some early texts refer to this category as "blood-injury-illness phobia."

Autophobia, also called monophobia, isolophobia, or eremophobia, is the specific phobia of isolation; a morbid fear of being egotistical, or a dread of being alone or isolated. Sufferers need not be physically alone, but just to believe that they are being ignored or unloved. Contrary to what would be implied by a literal reading of the term, "autophobia" does not describe a "fear of oneself". The disorder typically develops from and is associated with other anxiety disorders.

Autophobia can be associated with or accompanied by several other phobias such as agoraphobia, and is generally considered to be a part of the agoraphobic cluster. This means that autophobia has a lot of the same characteristics as certain anxiety disorders and hyperventilation disorders. The main concern of people with phobias in the agoraphobic cluster is getting help in case of emergency. This means people might be afraid of going out in public, being caught in a crowd, being alone, or being stranded.

Autophobia is not to be confused with agoraphobia (fear of being in public, or caught in large crowds), self-hatred, or social anxiety although it can be closely related to these things. It is its own phobia that tends to be accompanied by other anxiety disorders and phobias.

A fear of receiving calls may range from fear of the action or thought of answering the phone to fear of its actual ringing. The ringing can generate a string of anxieties, characterized by thoughts associated with having to speak, perform and converse. Sufferers may perceive the other end as threatening or intimidating. Anxiety may be triggered by concerns that the caller may bear bad or upsetting news, or be a prank caller.

Fear of making calls may be associated with concerns about finding an appropriate time to call, in fear of being a nuisance. A sufferer calling a household or office in which they know several people, may be concerned at the prospect of failing to recognize the voice of the person who answers, with resultant embarrassment. Some sufferers may be anxious about having to "perform" in front of a real or perceived audience at their end of the line: this is a particular problem for those required to use a phone in the workplace.

Fear of using the phone in any context (for either making or receiving calls) may be associated with anxiety about poor sound quality, and concerns that one or other party will not understand what has been said, resulting either in misunderstandings, or in the need for repetition, further explanation, or other potentially awkward forms of negotiation. These fears are often linked to the absence of body language over a phone line, and the individual fearing a loss of their sense of control. Sufferers typically report fear that they might fail to respond appropriately in the conversation, or find themselves with nothing to say, leading to embarrassing silence, stammering, or stuttering. Past experiences, such as receiving traumatic news, or enduring an unpleasant and angry call, may also play a part in creating fear.

A person with astraphobia will often feel anxious during a thunderstorm even when they understand that the threat to them is minimal. Some symptoms are those accompanied with many phobias, such as trembling, crying, sweating, panicked reactions, the sudden feeling of using the bathroom, nausea, the feeling of dread, fingers in the ears and rapid heartbeat. However, there are some reactions that are unique to astraphobia. For instance, reassurance from other people is usually sought, and symptoms worsen when alone. Many people who have astraphobia will look for extra shelter from the storm. They might hide underneath a bed, under the covers, in a closet, in a basement, or any other space where they feel safer. Efforts are usually made to smother the sound of the thunder; the person may cover their ears or curtain the windows.

A sign that someone has astraphobia is a very heightened interest in weather forecasts. An astraphobic person will be alert for news of incoming storms. They may watch the weather on television constantly during rainy bouts and may even track thunderstorms online. This can become severe enough that the person may not go outside without checking the weather first. In very extreme cases, astraphobia can lead to agoraphobia, the fear of leaving the home.

Mental health professionals often distinguish between generalized social phobia and specific social phobia. People with generalized social phobia have great distress in a wide range of social situations. Those with specific social phobia may experience anxiety only in a few situations. The term "specific social phobia" may also refer to specific forms of non-clinical social anxiety.

The most common symptoms of specific social phobia are glossophobia, the fear of public speaking and

the fear of performance, known as stage fright. Other examples of specific social phobia include fears of intimacy or sexual encounters, internet phobia, using public restrooms (paruresis), attending social gatherings, and dealing with authority figures.

Specific social phobia may be classified into performance fears and interaction fears, i.e., fears of acting in a social setting and interacting with other people, respectively. The cause of social phobia is not definite.

Symptoms of social phobia can occur in late adolescence when youths highly value the impressions they give off to their peers. Clinical experience of the prognosis of social phobia shows that it can prolong for many years but that it improves by mid life.

A childhood phobia is an exaggerated, intense fear “that is out of proportion to any real fear” found in children. It is often characterized by a preoccupation with a particular object, class of objects, or situation that one fears. A phobic reaction is twofold—the first part being the “intense irrational fear’ and the second part being “avoidance.”

Children during their developmental stages experience fears. Fear is a natural part of self-preservation. Fears allow children to act with the necessary cautions to stay safe. According to Child and Adolescent Mental Health, “such fears vary in frequency, intensity, and duration; they tend to be mild, age-specific, and transitory.” Fears can be a result of misperceptions. When a child perceives a threatening situation, his or her body experiences a fight or flight reaction. Children placed in new situations with unfamiliar objects are more likely to experience such reactions. These fears should be passing, a result of childhood development.

A childhood fear develops into a childhood phobia when it begins to interfere with daily living. “Acute states of fear can elicit counterproductive physiological reactions such as trembling, profuse perspiration, faint feelings, weakness in joints and muscles, nausea, diarrhea, and disturbances in motor coordination” It is not uncommon for frightened or anxious children to regress in a phase of development. For example, a kindergartener might begin to baby talk or wet the bed when faced with a threatening or particularly frightening situation. Childhood phobias exist in many different varieties and intensities and have a wide range from tolerable to incapacitating.

Cynophobia (from the "kýōn" "dog" and "phóbos" "fear") is the fear of dogs. Cynophobia is classified as a specific phobia, under the subtype "animal phobias". According to Dr. Timothy O. Rentz of the Laboratory for the Study of Anxiety Disorders at the University of Texas, animal phobias are among the most common of the specific phobias and 36% of patients who seek treatment report being afraid of dogs or cats. Although snakes and spiders are more common animal phobias, cynophobia is especially debilitating because of the high prevalence of dogs (for example, there are an estimated 25 million stray dogs in India, and an estimated 62 million pet dogs in the United States) and the general ignorance of dog owners to the phobia. The "Diagnostic and Statistical Manual of Mental Disorders" ("DSM-IV-TR") reports that only 12% to 30% of those suffering from a specific phobia will seek treatment.

The distinction between “normal” fears and phobias, a phobia (as defined by the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV)):

- An irrepressible persistent fear of an object, activity or situation esp. when the subject is exposed to unfamiliar people or possible criticism. In children, subject needs to be able to show a capacity for normal social reactions for their developmental stage, and when reactions occur they should happen among their peer group as well as with adults.

- Any exposure to the object or situation cause some form of unrestrained anxiety. In children this may be revealed by tantrums, crying, hysteria, or freezing.

- The fear reaction is excessive and unwarranted. NOTE: Adults who suffer from anxiety disorders usually accept that their fear reaction was disproportionate to the situation; however, children may not have the cognitive abilities to make this realization depending on age and maturity.

- The situation is avoided or endured with large amounts of stress and anxiety.

- The fear reaction interferes with a normal routine e.g. if a fear of elevators cause a person to avoid taller buildings.

- The duration is at least 6 months.

- The origin of the fear reaction is not directly caused by the physiological effects of a drug or substance or origin of anxiety is not better classified by another disorder e.g. Separation Anxiety Disorder.

- If another mental or medical condition is present, it is unrelated to the origin of the fear reaction.

Blood-Injection-Injury (BII) phobia is triggered when an individual comes in contact with or witnesses any type of injury or injection that results in exposure to blood. This fear can cause individuals, especially children, to become afraid of seeking medical attention if a mishap occurs.

A person may be diagnosed with taijin kyofusho if they feel as if their attitudes, behavior, and physical characteristics are inadequate in social situations. As a result of these feelings, they also experience persistent suffering in the form of emotional distress through shame, embarrassment, anxiety, fear, and other tense feelings that occur when confronted with social circumstances. In addition, individuals also worry about being unable to maintain healthy relationships with others. When it comes to socializing, taijin kyofusho sufferers avoid painful social and interpersonal situations, while simultaneously being averse to doing so. Those likely to develop taijin kyofusho have more of a temperamental characteristic of being hypochondriacal. The balance between introversion and extroversion in hypochondriacal temperament is geared more towards introversion. The introversion causes sufferers to focus on themself and problems they have, and by fixating on their weaknesses they become more anxious and depressed.

Though scopophobia is a solitary disorder, many individuals with scopophobia also commonly experience other anxiety disorders. Scopophobia has been related to many other irrational fears and phobias. Specific phobias and syndromes that are similar to scopophobia include erythrophobia, the fear of blushing (which is found especially in young people), and an epileptic's fear that being looked which may itself precipitate such an attack. Scopophobia is also commonly associated with schizophrenia and other psychiatric disorders. It is not considered indicative of other disorders, but is rather considered as a psychological problem that may be treated independently.

Sociologist Erving Goffman suggested that shying away from casual glances in the street remained one of the characteristic symptoms of psychosis in public. Many scopophobia patients develop habits of voyeurism or exhibitionism. Another related, yet very different syndrome, scopophilia, is the excessive enjoyment of looking at erotic items.