Your heart is racing. Your gut is unsettled. You haven't slept properly in weeks, and you're not sure what's going on. In my experience, this is often how anxiety introduces itself. Not as a feeling, but as a set of physical symptoms that bring people in to see their GP before they've even considered anxiety as the cause.

That's not a failure to recognise your own mental health. It's just how the nervous system works. The body and the mind are not separate systems, they're deeply, chemically connected. And when anxiety activates, the body is often where you feel it first.

So what's actually happening?

The physiology: what anxiety does to your body

When the brain perceives a threat, real or imagined, physical or psychological, it triggers what's known as the fight-or-flight response. This is a survival mechanism, and it's spectacularly effective at keeping you safe in a genuine emergency.

The brain signals the adrenal glands to release adrenaline and cortisol. Adrenaline acts within seconds: your heart rate increases, your breathing quickens, blood is diverted to your muscles, and your senses sharpen. Cortisol follows, sustaining this state of readiness over a longer period.

In a situation where you need to run or fight, this is exactly what you want. The problem with anxiety, particularly chronic anxiety, is that the same system activates in response to a difficult conversation, a work deadline, or a worry that isn't going away. The threat is psychological, but the body responds as if it's physical.

"The body responds the same way to a lion and to a looming deadline. The difference is one of them goes away."

And over time, repeated activation of the stress response, without the physical release of running or fighting, means these symptoms persist and accumulate.

The physical symptoms of anxiety, by system

Tap or hover each area in the diagram below to explore how anxiety affects different parts of the body. The symptoms are real, measurable, and physiologically explainable, not "just in your head."

Interactive diagram

Cardiovascular
Heart palpitations
Cardiovascular
Chest tightness
Respiratory
Shortness of breath
Neurological
Dizziness
Gastrointestinal
Nausea & gut symptoms
Gastrointestinal
Appetite changes
Neurological
Restlessness
Sleep
Insomnia
Select a symptom above
Understanding anxiety's physical effects
The physical symptoms of anxiety span multiple body systems, from the cardiovascular system to the gut, muscles, and sleep centres. Each one is a direct result of the stress response, not something you're imagining.
The physical symptoms of anxiety span multiple body systems, from the cardiovascular system to the gut, muscles, and sleep centres. Each symptom is a direct physiological response to stress hormones, not imagination.

Anxiety you've never named

One of the patterns I see most often in practice is this: someone has been living with anxiety for years, sometimes decades, without ever calling it that. They've been managing a racing heart, or recurring gut problems, or a jaw that aches every morning, or a sleep pattern that's never quite worked. They've attributed it to stress, or getting older, or just the way they are.

The turning point is often unrelated to mental health. It might be a blood pressure reading that's come up high for the second time. Or a repeat presentation for IBS symptoms that haven't responded to treatment. Or someone who mentions almost in passing that they haven't slept through the night in three years.

None of these conversations need to be difficult. Anxiety isn't a character flaw or a sign of weakness, it's a nervous system that's been running on high alert for too long. The body is just trying to tell you something.

A note on men's health

Men are statistically less likely to present with anxiety as a primary concern. What I often see instead: fatigue, irritability, gut issues, or sleep problems that have been going on for a while. If any of this resonates, it's worth bringing to your GP, not because there's something wrong with you, but because there are good options, and you don't have to manage it alone.

See also: Mental Wellbeing at Pro Health Care Glenelg

Other physical symptoms of anxiety worth knowing

Beyond the most commonly recognised symptoms, anxiety can show up in ways that are genuinely surprising to patients, and sometimes to clinicians who aren't looking for them:

  • Muscle tension and jaw clenching (bruxism)
  • Tension headaches
  • Dry mouth
  • Sweating, particularly at night
  • Tingling or numbness in hands or face
  • Frequent urination
  • Difficulty concentrating or brain fog
  • Fatigue and low energy
  • Heightened sensitivity to light or sound
  • Skin flushing or feeling hot

Many of these overlap with other conditions, thyroid dysfunction, iron deficiency, cardiovascular disease, and others. Your GP's job is to work through these possibilities with you, not to assume anxiety is the explanation without ruling out other causes first.

When to see your GP

The short answer: if physical symptoms are affecting your daily life and you're not sure why, a GP consultation is the right starting point. We can investigate physical causes, take a full history, and have a proper conversation about what's going on, without rushing you through it.

You don't need to be in crisis. You don't need a diagnosed anxiety disorder. You just need to be in a situation where something isn't quite right and you'd like to understand it better.

If anxiety is identified, there are good options. Non-pharmacological approaches, structured exercise, sleep hygiene, evidence-based breathing techniques, and talking therapy, form the foundation of most treatment plans. Medications can play a role for some patients as part of a broader plan, but they're never the first or only conversation. The goal is to give you tools that work for your life, not a one-size-fits-all protocol.

For patients who would benefit from regular psychological support, I can prepare a Mental Health Treatment Plan, giving you access to psychology sessions through a structured referral pathway. It's worth understanding this option exists before you assume psychological support is out of reach.

Something here
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A GP consultation is the right starting point, to investigate physical causes, have the conversation, and work out what comes next.

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Common questions about anxiety and the body

Yes. Anxiety triggers the release of adrenaline, which causes the heart to beat faster and muscles around the chest to tighten. This can feel like chest tightness, pressure, or even sharp pain. However, chest pain should always be assessed by a doctor to rule out cardiac causes, especially if it's new, severe, or accompanied by breathlessness, sweating, or pain radiating to the arm or jaw.
Yes. Adrenaline and other stress hormones directly stimulate the heart, causing it to beat faster, harder, or irregularly. This is one of the most common physical symptoms of anxiety. If palpitations are new, frequent, or accompanied by dizziness or chest pain, it's worth seeing your GP to rule out other causes.
The gut and brain are directly connected via the vagus nerve, a pathway sometimes called the gut-brain axis. When anxiety activates the stress response, it disrupts normal gut movement, increases gut sensitivity, and can alter the balance of gut bacteria. This produces symptoms like nausea, cramping, loose stools, bloating, and urgency that can mimic irritable bowel syndrome.
Yes. Anxiety keeps the nervous system in a state of heightened alert, making it hard to fall asleep and stay asleep. Elevated cortisol levels disrupt the normal sleep-wake cycle. Anxious thoughts at bedtime, replaying the day, worrying about tomorrow, further prevent the nervous system from downregulating into sleep. Poor sleep then worsens anxiety the next day, creating a cycle.
Yes. Hyperventilation during anxiety, breathing faster and shallower than normal, reduces carbon dioxide levels in the blood, which can cause dizziness, lightheadedness, and tingling in the hands or face. Anxiety also affects blood pressure regulation, which can contribute to a brief drop in blood pressure when standing.
Physical symptoms should always be investigated rather than assumed to be anxiety, especially symptoms like chest pain, shortness of breath, or palpitations. Your GP's role is to assess for physical causes first, and once those are ruled out, to consider anxiety as the explanation. If anxiety is identified, it's very treatable, and addressing it usually resolves the physical symptoms too.
Anxiety itself is not dangerous, it is the nervous system doing exactly what it evolved to do. However, chronic anxiety that goes untreated places ongoing strain on the cardiovascular system, disrupts sleep, affects gut health, and significantly reduces quality of life. The good news is that anxiety responds well to treatment, including lifestyle approaches, talking therapies, and in some cases medication.
If anxiety is affecting your sleep, your work, your relationships, or your daily life, or if you're experiencing physical symptoms you can't explain, it's worth bringing to your GP. You don't need to be in crisis to seek help. A GP consultation is the right starting point: we can assess whether physical causes need to be ruled out, discuss what's going on, and talk through your options.
Dr David Nguyen, GP at Pro Health Care Glenelg, Adelaide
Written by
Dr David Nguyen
MBBS · FRACGP · GPMHSC Accredited

I'm a GP at Pro Health Care Glenelg with a particular interest in mental wellbeing and the way the mind and body interact. In my experience, patients with anxiety most often present with physical symptoms first, and recognising that connection is often the first step toward feeling better.

Learn more about Dr David Nguyen → First published: 9 April 2026 · Last reviewed: 9 April 2026