If you avoid the ocean at all costs or refuse to watch movies set in deep water, you may be experiencing thalassophobia.

Most people have a “healthy” fear of the ocean. After all, the ocean is deep, dark, and largely unknown. It takes a rare person to feel comfortable jumping off a boat several miles offshore.

But people with thalassophobia have a very intense and irrational fear of any deep body of water. Even seeing a photo of the ocean may trigger a panic attack.

While living with thalassophobia can be challenging, try to keep in mind that help is available and that — like other specific phobias — recovery is possible.

Thalassophobia is a type of phobia characterized by a persistent and intense fear of deep water, such as an ocean or a lake.

People with thalassophobia either avoid deep bodies of water altogether or endure them with overwhelming anxiety. The level of fear they experience is extremely disproportionate to any actual danger.

While thalassophobia isn’t recognized as a distinct disorder in the Diagnostic Manual of Mental Disorders, fifth edition (DSM-5), its symptoms fall under the diagnostic criteria for “Specific Phobia: Natural Environment Type.”

Some other phobias are closely related to thalassophobia, and their symptoms may overlap. These phobias include:

  • aquaphobia (fear of water)
  • bathophobia (fear of depths)
  • megalohydrothalassophobia (fear of large underwater creatures or objects)
  • cymophobia (fear of waves)
  • nyctophobia (fear of the dark)
  • antlophobia (fear of floods)

Thalassophobia involves a variety of psychological and physical symptoms, similar to those of a panic attack.

These symptoms may occur when a person with thalassophobia thinks about, sees, or encounters a deep body of water.

Emotional or psychological symptoms of thalassophobia may include:

  • intense and sudden onset of anxiety or fear
  • dread
  • panic
  • fear of losing control
  • insomnia
  • racing thoughts
  • avoidance of the feared object or situation

Physical symptoms of thalassophobia include:

  • trembling
  • rapid breathing or breathlessness
  • rapid heart rate
  • sweating
  • headache
  • dry mouth
  • dizziness
  • chest pain
  • nausea
  • chills
  • confusion

Triggers of thalassophobia may include thinking about or encountering:

  • the ocean
  • lakes
  • boats
  • swimming
  • scuba diving
  • submarines
  • sea creatures (realistic or mythical)
  • photos or movies of any of the above

Though research specifically on thalassophobia is lacking, a variety of genetic, physiological, environmental, and familial factors may contribute to the development of specific phobias like thalassophobia.


Anxiety disorders, including phobias, often run in families. One 2014 study found that of 21 individual fears/phobias, 14 participants (67 percent) had an estimated heritability of 30% to 50%.

Brain circuitry

Fear is an emotion that gets triggered when we perceive a risk to our safety or the safety of others. To prepare for this perceived danger, our bodies may engage in the “fight, flight, or freeze” reactions through specific brain circuits and mechanisms.

A 2017 research review with animal studies showed that when there is a dysfunction in these brain circuits, it can result in anxiety disorders, such as post-traumatic stress disorder (PTSD) and specific phobias.


Some phobias are triggered by an initial bad experience or traumatic event. In the case of thalassophobia, a person may have had a near-drowning experience in the ocean. Or perhaps, they witnessed another person fall off a boat into deep water.

Phobias that stem from a traumatic event are called “experiential-specific phobias.” Those that develop without a traumatic event are called “nonexperiential-specific phobias.” (Keep in mind that PTSD is always caused by a traumatic event.)

Family dynamics

Growing up in an anxious family environment may also play a role in the development of phobias. This is because fear can be a learned emotion.

For instance, a child whose mother is very fearful of the ocean, may pick up on that anxiety and start to fear the ocean themself.

Thalassophobia isn’t recognized as a distinct disorder in the DSM-5, but its symptoms fall under the diagnostic criteria for “Specific Phobia: Natural Environment Type.”

According to the DSM-5, a diagnosis of thalassophobia would be given if a person’s symptoms met the following criteria:

  • The person experiences a significant fear or anxiety about a specific object or situation. In the case of thalassophobia, this would be a fear of deep bodies of water.
  • The trigger (deep water) almost always leads to intense and sudden fear or anxiety.
  • The fear is disproportionate to the actual danger of the specific object or situation.
  • Triggers (ocean, lakes, photos or movies of deep water, etc.) are actively avoided or endured with intense anxiety.
  • The phobia (fear of deep water) results in clinically significant distress or an impairment in functioning.
  • The phobia (fear of deep water) is persistent, typically lasting for 6 months or more.
  • The phobia (fear of deep water) is not better explained by the symptoms of another mental disorder, such as obsessive-compulsive disorder (OCD) or PTSD.

Treatment for thalassophobia may include one or a combination of the following:

  • Cognitive-behavior therapy (CBT). When it comes to specific phobias, CBT often involves desensitization or exposure therapy, in which people are gradually exposed to their triggers until their anxiety begins to lessen. In the case of thalassophobia, a person might begin by looking at photos of deep water, progress to watching films with deep water, and ultimately go to the beach or get on a boat.
  • Medication. Benzodiazepines, such as Valium or Xanax, or beta-blockers, such as propranolol, may be prescribed to help reduce anxiety, particularly in specific situations such as needing to get on a boat.
  • Relaxation techniques. Deep breathing, meditation, and mindfulness practices may also help reduce anxiety symptoms.

Because untreated phobias can significantly affect a person’s life, it’s highly recommended to seek treatment.

For instance, a person with thalassophobia might do everything in their power to avoid going to the lake or the ocean. They may even avoid movies or books featuring the ocean, ships, or ocean life.

Avoiding a fear allows it to remain for an extended period of time — or get even worse. Then, when a trigger is accidentally encountered, you may experience a panic attack.

Seeking treatment may make it easier to manage your thalassophobia as you learn coping and recovery strategies.

There are several things you can do at home to help lessen your fear of deep water. These include long-term practices, like meditation, and short-term tools, such as visualization or deep breathing.


People with phobias tend to have greater anxiety levels overall. In fact, according to a 2012 study, a person with one phobia is 83 percent more likely to have another phobia.

Long-term practices, such as meditation, may help reduce anxiety levels in the long run.

Meditation works by training the brain and body to achieve a very relaxed state called the “relaxation response.” This is essentially the opposite of the fight, flight, or freeze response.

In a brain scan study from 2018, researchers discovered that people who had been meditating for many years showed reduced amygdala activation when they looked at emotionally-negative images.

The amgydala is the part of your brain involved in the fight, flight, and freeze response and also responsible for detecting threats and fear conditioning.

If you’re new to meditation, consider using a meditation app, online tool, or book to help you get started.

Visualization techniques

Your imagination may be a useful tool to help you practice encountering your fears. In the case of thalassophobia, you would visualize certain situations involving deep water and imagine yourself successfully dealing with them.

For instance, you can try the following:

  1. Imagine you’re standing on a beach in the shallow water.
  2. Breathe deeply and imagine how it would feel to not have any fear.
  3. Slowly “walk” deeper into the ocean. (You can imagine that you’re wearing a life vest.)
  4. Imagine you’re floating on your back without any fear.

If the thought of trying a visualization technique by yourself seems like too much at the moment, consider asking your therapist for guidance if you have one, or reach out to a trusted friend or family member to be by your side as you go through the exercise.

Deep breathing

Deep breathing exercises can be done at home or when you encounter one of your triggers.

For instance, you can try the following:

  1. Take a long deep breath (imagine you are slowly breathing in the smell of your favorite food).
  2. Release your breath all the way as if you were blowing out candles on a birthday cake.

Do this several times until you feel your body relax.

Being afraid of bodies of water like the ocean or a lake can be challenging, and avoiding your fear may not always be possible and won’t help you in the long run.

If you think you have thalassophobia, consider reaching out to a mental health professional who specializes in phobias. They may help you on your journey toward recovery.

If you’re interested in support from others living with specific phobias, The Tribe may be worth looking into, which is an online platform for support groups for people with various anxiety disorders.