Flooding requires you to stay present with your fear until your fight-or-flight response calms down.

Most of us do everything we can to avoid our fears. Whether it’s a fear of heights, closed-in spaces, or meeting new people, we go to great lengths to avoid airplanes, elevators, and large parties.

But what happens if you’re forced to face your biggest fears head-on with no chance of escaping them? This is a real type of exposure therapy called “flooding.”

As the name suggests, flooding involves exposing you to your greatest fear for a prolonged period until your brain and body eventually calm down.

While it’s not common in clinical practice, there’s some research backing the approach.

Flooding therapy is an intensive type of exposure therapy in which you must face your fear at a maximum level of intensity for an extended amount of time. There’s no avoiding the situation and no attempt on the therapist’s part to reduce your anxiety or fear.

This exposure technique is different fromsystematic desensitization, another type of exposure therapy, in which you gradually and progressively work your way through your least- to most-feared stimuli.

Rather, flooding begins with the most difficult stimuli all at once and sustains this situation until your body’s fight-or-flight response exhausts itself.

How does flooding therapy work?

Once you’ve given your consent to participate in this intensive form of therapy, flooding is typically performed “in vivo,” meaning it’s performed in person or in a real-life situation. When this is impossible, flooding may also take place via images, props, or virtual reality.

During flooding, you’re exposed to your most feared stimuli, such as heights or spiders, in a safe and controlled environment for an extended time.

During this time, you can use calming techniques to help you through the process, but your therapist makes no particular effort to alleviate your fears. Your therapist, however, may likely start with some psychoeducation before beginning the flooding.

They will likely explain the method of flooding therapy — that the nervous system is sending a false alarm to your brain about your phobia and that only sticking it out through the whole exposure can get rid of this false alarm.

In other words, once your body’s fight-or-flight response has exhausted itself, your brain can recognize that nothing bad has happened to you. The goal is to positively condition your mind to stop reacting severely when presented with that trigger in the future.

Flooding session times vary but may last 2-3 hours. Very often, the goal is to complete the treatment in one session only — often lasting several hours. In some cases, the client may need to repeat the process several times.

While flooding is understandably quite stressful for the client, it can also be stressful for the therapist. In a study of 25 participants with specific phobia, researchers found that clients released slightly higher levels of stress hormones during flooding than during gradual therapy.

While therapists showed no excessive release of stress hormones during gradual therapy, they did show heightened stress hormones during flooding therapy.

Flooding example

If you live with claustrophobia, a flooding session might involve sitting in an extremely small, crowded room for several hours. This might even involve an elevator or a closet.

A proper flooding session would require that you stay in the room until your panic response has fully subsided. The therapist would make no effort to help you work through the panic, and there’s no option for avoidance.

Recent research on flooding therapy is limited, but a few decades-old studies suggest that it can work.

An older 1985 study of participants with a fear of heights found that brief exposures yielded no positive results, while prolonged exposure to heights led to the greatest benefits, particularly among participants who had been trained in coping self-statements (e.g. “I can handle this.”).

In another older, small 1989 clinical trial of 24 Vietnam veterans with post-traumatic stress disorder (PTSD), researchers found that veterans showed improvement in the re-experiencing dimension of PTSD (flashbacks, nightmares, etc.) after flooding treatment, compared to those who were still on a waiting list.

Flooding isn’t for everyone, and trauma and hospitalization are potential risks for some people, particularly those with heart problems.

Flooding does have the advantage of being time- and cost-effective, as it may only require one or very few sessions, compared to numerous sessions with gradual therapy.

When flooding treatment is successful, and you’ve thoroughly worked through your body’s alarm stage, you achieve a greater sense of control over your anxiety and overall experiences.

When is flooding therapy used?

Flooding may be used to treat the following conditions:

Exposure and response prevention (ERP) is the first-line treatment for OCD. The flooding technique can be used within ERP.

Typically, ERP uses a systematic step-by-step approach in which you’re gradually exposed to your fears from least to greatest until they lose their power. If you prefer a flooding technique over a more gradual approach, however, you’ll begin with your worst fear from the get-go.

Flooding for OCD is supposed to teach those with the condition they can get through their worst-case scenario without being allowed to use their favored rituals or compulsions. This technique may be too much too quickly for someone with OCD and could lead to regression of compulsions and obsessions.

Most of us try to avoid our fears at all costs, but this leads to a life of constant avoidance and anxiety. With flooding therapy, you jump in head first and face your biggest fear right away, instead of gradually.

During flooding, you stay present with your fear until your body’s fight-or-flight response relaxes. This intense exposure may help you realize that you’re actually OK and allows your brain to form a new association with your fear.

Some people may successfully use flooding to trade in a feeling of dread for a welcome sense of calm. For others, the technique may be too harsh, and the gradual approach of exposure therapy — more common in practice — may be more effective.