Panic Attack: What Happens in Your Body and How to Break the Cycle

What Is a Panic Attack — and Why It Strikes You

A panic attack overtakes you without warning. A pounding heart, breathlessness, tingling in your hands, an overwhelming sense that you are losing control — or worse, that you are dying. It lasts five to twenty minutes, but the fear that it will return persists for months. In the Netherlands, an estimated one in five adults experiences at least one panic attack in their lifetime. For those who experience it more often, the fear of the attack itself becomes the problem: a cycle that sustains itself.

What few people know: a panic attack is not a psychological weakness. It is a measurable neurological phenomenon — a derailed fight-or-flight response of your autonomic nervous system. And precisely because the mechanism is physiological, there are physiological points of entry to break it.

Recognising the Symptoms: More Than Just Fear

The symptoms of a panic attack are overwhelmingly physical. That is exactly what makes it so frightening — your body behaves as though there is acute danger, while you rationally know that there is not.

The most common symptoms:

An accelerated heartbeat and palpitations. Pressure on the chest. Hyperventilation or the feeling of not getting enough air. Tingling in the hands, feet, or face. Nausea. Dizziness. A sense of unreality — as if you are standing beside yourself. And the conviction, deep and illogical, that you are about to die or lose your mind.

These symptoms are not “imagined.” They are the direct consequence of a sympathetic dysregulation: your nervous system shifts into an emergency mode that does not match the situation. The question is not whether the symptoms are real — they are. The question is why your system produces them without cause.

The Mechanism: Your Nervous System in Overdrive

Your autonomic nervous system consists of two branches. The sympathetic branch activates: heart rate up, breathing accelerated, muscles tensed, blood directed to the limbs. The parasympathetic branch brakes: heart rate down, digestion on, recovery active. In a healthy system, these two alternate continuously — a dynamic equilibrium.

Under chronic stress, that equilibrium shifts. The sympathetic branch is permanently set too high. Your baseline heart rate variability — the subtle variation between heartbeats that reflects healthy autonomic flexibility — declines. Your cortisol remains elevated. The vagus nerve, the long nerve that functions as the brake on the sympathetic system, loses its tone.

And then, at a random moment — in bed, in the supermarket, during a meeting — the system overshoots. Not because something bad is happening, but because the threshold has become so low that any small signal triggers the cascade. That is the panic attack: an alarm going off in an empty building.

The research data are clear. People with recurring panic attacks consistently show reduced vagal tone, elevated baseline sympathetic activity, and disrupted HRV patterns. It is not a matter of “thinking too much.” It is a nervous system that has structurally lost its balance.

Panic Attacks Caused by Stress and Burnout: The Hidden Connection

A pattern we consistently observe at NEST: panic attacks do not manifest only in anxiety disorders. They appear increasingly as a symptom of burnout and prolonged overload. The autonomic nervous system that has been running in the red zone for months eventually loses the ability to shift back down.

The first panic attack then comes seemingly out of nowhere. You were functioning, you kept working, you had everything under control — until your body decided that it had had enough. In that context, the panic attack is not a separate problem. It is the alarm signal of a system that has long been overloaded.

That also explains why conventional approaches — cognitive behavioural therapy, breathing exercises, medication — are sometimes not enough. They address the symptom or the cognitive layer, but do not always reach the physiological foundation: a vagus nerve that has lost its braking function, a sympathetic branch that is structurally set too high, neuroinflammation that has lowered the stress threshold.

Hyperbaric Oxygen Therapy and the Autonomic Nervous System

Hyperbaric oxygen therapy (HBOT) works at a level that most interventions do not reach: the cellular and neural infrastructure of your stress regulation.

During a session you breathe pure oxygen under increased pressure — typically 1.5 to 2.0 atmospheres. The oxygen concentration in your blood and tissues rises by a factor of four to five. This has three effects that are directly relevant to panic attacks:

Vagal stimulation. Research shows that HBOT increases the activity of the vagus nerve. The vagus nerve is the physiological brake on your sympathetic system. Increased vagal tone means your body returns to a resting state more quickly after stress — precisely the mechanism that fails during panic attacks.

Dampening neuroinflammation. Chronic stress causes low-grade inflammation in brain regions that regulate the stress response, including the amygdala and the prefrontal cortex. HBOT modulates this neuroinflammation and protects neuronal structures. The result: a higher threshold before the alarm system goes off.

Restoring heart rate variability. HRV is the gold standard for autonomic balance. Studies show that HBOT significantly improves HRV — a direct measure of the recovery of parasympathetic function. A higher HRV means more resilience: your system can better handle stimuli without overshooting.

The NEST Protocol: A Layered Approach

At NEST we combine HBOT with complementary modalities that address the same nervous system from different angles. This is no coincidence — the autonomic nervous system responds most strongly to stacked, consistent signals.

Vagus nerve stimulation reinforces the HBOT effect by training vagal tone directly. Red light therapy contributes to cortisol regulation and cellular recovery. Contrast therapy — the alternation of cold and heat — forces the autonomic system to switch between sympathetic activation and parasympathetic recovery, building flexibility in the process.

The goal is not to suppress panic attacks. The goal is to restore the system that produces them to a state in which the threshold lies high enough to absorb normal stimuli without derailing. Not dampening, but regulation. Not control, but resilience.

What You Can Do Today

If you experience panic attacks, the first thing you can do is to understand that your body is doing what it has learned to do under pressure. It is not a failure. It is a system offering protection at a moment when that protection is not needed.

The second step is to take the physiological layer seriously alongside the mental layer — therapy, guidance, self-care. Your nervous system is not an abstraction. It is a measurable, influenceable system with concrete points of entry.

Would you like to know how your autonomic balance stands and which protocol is most effective for your situation? At NEST we measure your HRV, map your stress response, and assemble a personalised recovery protocol that works at the level where the panic attack originates — not where you feel it, but where it begins.

Key message: A panic attack is not a mystery and not a fate. It is a measurable dysregulation of your autonomic nervous system, caused by chronic stress that has weakened the vagal brake. Hyperbaric oxygen therapy, combined with targeted neurostimulation, restores the balance your body has lost. The cycle can be broken — and it begins with understanding the mechanism.