Anxiety Symptoms Nobody Talks About — The Physical Signs explained by Doctor

Anxiety Symptoms Nobody Talks About: The Physical Signs Explained | Dr. Reem Aslam
Anxiety · Mental Health · MBBS · CBT · Physical Symptoms

Anxiety Symptoms Nobody Talks About: A Medical Student Explains the Physical Side

Anxiety isn't just worrying. It's a full-body physiological response, and the physical symptoms are real.

Anxiety sends people to the emergency department with chest pain that turns out not to be cardiac. It causes dizziness that gets investigated as vertigo. It produces GI symptoms that get scoped and biopsied. And then the tests come back normal, and the patient is told "it's just anxiety," in a tone that implies it isn't real.

It is real. The physical symptoms of anxiety are driven by measurable physiological changes. Understanding them doesn't make them go away, but it does make them less terrifying, and that matters clinically.


The Physiology First

Anxiety activates the sympathetic nervous system via the hypothalamic-pituitary-adrenal (HPA) axis and the locus coeruleus. Noradrenaline and adrenaline are released. Cortisol follows.

The core stress hormones
Adrenaline + Cortisol
Heart rate up. Blood redirected to muscles. Digestion slowed. Pupils dilated. Sweating starts. This is your fight-or-flight system, and it's doing exactly what it evolved to do, just at the wrong moment.

The problem in anxiety disorder is that this system activates without an acute threat, or activates disproportionately to one. The body responds identically whether you're being chased or sitting in a meeting room.


The Physical Symptoms (and Why They Happen)

Cardiovascular

Palpitations and racing heart

Adrenaline directly stimulates cardiac beta-1 receptors, increasing heart rate and contractility. You feel your heart pounding. Sometimes irregular beats (ectopics) become more noticeable during anxiety. This is real cardiac activity, just not dangerous in a structurally normal heart.

Chest pain or tightness

Two mechanisms here: intercostal and chest wall muscle tension (anxiety causes sustained low-level muscle contraction), and hyperventilation changing chest mechanics. The pain is musculoskeletal, not ischaemic. It's still painful. Distinguishing it from cardiac chest pain requires proper assessment, especially if it's your first episode, you're over 40, or you have cardiovascular risk factors.

Respiratory

Hyperventilation and shortness of breath

Anxiety drives faster, shallower breathing. This drops CO2 levels in the blood (hypocapnia). Lower CO2 causes vasoconstriction, tingling in hands and lips, lightheadedness, and paradoxically, a feeling of not getting enough air. This is the anxiety-hyperventilation loop: the breathlessness makes you more anxious, which makes you breathe faster.

Neurological

Dizziness and lightheadedness

Hypocapnia from hyperventilation causes cerebral vasoconstriction. Less blood flow to the brain means lightheadedness, and sometimes a genuine feeling of unreality (derealisation). People describe the world looking slightly flat or distant. This is pharmacologically predictable: you're literally reducing cerebral blood flow.

Tingling in hands, lips, and face

The same hypocapnia changes the electrical charge on calcium channels in peripheral nerves. This causes tingling (paraesthesia), particularly in the hands, feet, and around the mouth. It's alarming if you don't know why it's happening. It resolves when CO2 levels normalise, which happens with slower breathing.

Headaches

Tension-type headaches are the most common headache type, and anxiety is one of the main drivers. Sustained contraction of the neck, scalp, and shoulder muscles creates a band-like pressure around the head. These differ from migraines: no aura, no nausea, bilateral, and worse through the day.

Gastrointestinal

Nausea and stomach upset

The gut-brain axis runs bidirectionally via the vagus nerve. Anxiety shifts the autonomic balance toward sympathetic dominance, which slows gut motility and reduces digestive secretions. You feel nauseous. This is why "butterflies in your stomach" is not a metaphor: it's real gastric smooth muscle response to autonomic stimulation.

Diarrhoea

Acute anxiety increases colonic motility. Cortisol increases gut permeability and alters the microbiome composition with chronic anxiety. The "I need the bathroom before something stressful" response is a known physiological phenomenon. In IBS, anxiety often triggers flares through the same gut-brain mechanism.

Musculoskeletal

Muscle tension and pain

Sustained low-level muscle tension is a core feature of generalised anxiety disorder (GAD). People hold their jaw, shoulders, and neck contracted without noticing. Over weeks, this causes genuine pain: jaw pain, neck pain, shoulder pain, and headaches. It's not imagined; the muscles are genuinely working harder than they should be at rest.

Fatigue

Chronic anxiety is metabolically expensive. Running your stress response at low-level intensity for weeks or months burns energy, disrupts sleep architecture, and keeps cortisol elevated. Elevated cortisol chronically disrupts both REM sleep and deep slow-wave sleep. You're exhausted but wired. Both at once.


The error people make is thinking that if a symptom is caused by anxiety, it's not a real symptom. The nausea, the heart pounding, the breathlessness: these are real physiological events, not performances.

When These Symptoms Need Investigating Anyway

Investigate before attributing to anxiety

Chest pain, especially in someone with cardiovascular risk factors (smoking, hypertension, diabetes, family history), needs an ECG and troponin at minimum. Palpitations with a history of fainting warrant a 24-hour Holter monitor. Dizziness with associated hearing loss or nystagmus needs ENT or neurology, not reassurance. Significant unexplained weight loss with anxiety symptoms requires a TSH to rule out hyperthyroidism. The anxiety label should come after exclusion, not before investigation.

What Actually Treats Anxiety's Physical Symptoms

CBT
Strongest evidence base. 12 to 20 sessions. Addresses thought patterns and behavioural avoidance that perpetuate anxiety.
SSRIs/SNRIs
First-line pharmacotherapy. Take 4 to 6 weeks to work fully. Sertraline, escitalopram, and venlafaxine have the best evidence for anxiety disorders.
Diaphragmatic breathing
Directly reverses hyperventilation physiology by raising CO2. 4-7-8 breathing or box breathing (4 counts each direction) with proven physiological effect.
Exercise
Aerobic exercise reduces anxiety by comparable effect size to medication in meta-analyses. 150 minutes per week is the target, with intensity that raises heart rate.

Beta-blockers (propranolol specifically) are sometimes used for the physical symptoms of situational anxiety, particularly palpitations and tremor. They block adrenaline's cardiac effects. They don't treat the underlying anxiety; they manage specific peripheral symptoms.

Benzodiazepines (diazepam, lorazepam) are effective short-term but carry dependence risk with any regular use beyond 2 to 4 weeks. They're useful for acute management (panic attacks, procedural anxiety) and not appropriate as ongoing therapy.

The Hyperventilation Reset (Genuinely Useful)

If you're in a panic attack or acute anxiety with physical symptoms, the breathing technique that has the clearest physiological basis is controlled diaphragmatic breathing at a rate of around 6 breaths per minute. Inhale slowly for 5 seconds, exhale for 5 seconds. This activates the parasympathetic nervous system and restores CO2 levels.

The exhale is the important part. Longer exhale than inhale (5 seconds in, 7 out) has an even stronger vagal activation effect.

The Summary

Anxiety produces real physical symptoms via real physiological mechanisms. The chest pain, dizziness, GI upset, and tingling are not invented. Understanding why they happen is often the first step toward managing them, because the "this is anxiety, not a heart attack" cognitive reappraisal during a panic attack requires understanding the physiology well enough to believe it.

If you've been managing physical symptoms for a long time without the anxiety piece being addressed, that's the gap. The symptoms and the anxiety are the same problem.

Dr. Reem Aslam, MBBS

Physician and evidence-based medical writer.

This article is for educational purposes only. If you are experiencing anxiety symptoms, please speak with a qualified mental health professional or your GP. If you are in crisis, please contact a crisis helpline immediately.

Comments

Popular posts from this blog

IBS vs. IBD: What’s the Difference and Why It Matters for Your Gut Health

"The Miracle of Hydration: How Water Can Improve Your Health and Vitality"