Panic Disorder — Symptoms, Causes & Treatment | MyMedicPlus

Panic disorder is an anxiety disorder characterised by recurrent, unexpected panic attacks — discrete episodes of intense fear or discomfort, peaking within minutes, arising without an identifiable trigger in a situation that would not normally provoke fear — accompanied by at least one month of persistent anticipatory anxiety about future attacks, worry about their implications (fear of having a heart attack, 'going crazy', or losing control), and/or significant maladaptive behavioural changes designed to avoid triggering further attacks (such as avoiding exercise, caffeine, or going out alone). A single panic attack does not constitute panic disorder — the diagnosis requires recurring unexpected attacks plus the characteristic persistent worry or behaviour change. Panic disorder has a lifetime prevalence of 2-3% in the general population, with peak onset in young adulthood (15-30 years) and a 2:1 female-to-male ratio. It runs a chronic, relapsing-remitting course in the majority of cases without treatment — and frequently leads to progressive disability through the development of agoraphobia (in 30-50% of patients), social withdrawal, occupational impairment, and secondary depression. Panic disorder is one of the most costly anxiety disorders in terms of healthcare resource utilisation: the characteristic mimicry of cardiac disease (chest pain, palpitations, breathlessness, dizziness) leads to an average of 5-7 years of cardiology and emergency department investigations before the psychiatric diagnosis is made. Both CBT and SSRIs are highly effective treatments, achieving remission in 70-80% of patients.

Biological and neurological mechanisms: panic disorder arises from dysregulation of the central fear network — pathological hyperactivation of the amygdala and its efferent connections to the locus coeruleus (noradrenaline-producing brainstem nucleus), the periaqueductal grey (defensive behaviour generator), and the hypothalamus (autonomic responses). Abnormal noradrenergic (excessive noradrenaline release causing sympathetic surge), serotonergic (reduced serotonin modulation of fear circuits), and GABA-ergic neurotransmission are central. Hypersensitivity to CO2 inhalation (a reliable laboratory panic provocation in patients but not controls) reflects abnormal suffocation alarm signalling in the brainstem. Genetic factors: heritability is approximately 40%; first-degree relatives of people with panic disorder have a 5x increased lifetime risk; polymorphisms in the adenosine A2A receptor gene (ADORA2A) are associated. Cognitive model (Clark, 1986): the maintenance mechanism of panic disorder is catastrophic misinterpretation of normal or anxiety-amplified bodily sensations — a racing heart is interpreted as an impending heart attack; dizziness is interpreted as fainting or impending death; these catastrophic thoughts amplify fear, produce further physiological arousal, creating a self-perpetuating panic cycle. Anxiety sensitivity (the belief that anxiety symptoms are harmful) is the most powerful cognitive risk factor. Childhood risk factors: separation anxiety disorder in childhood (a major precursor); behavioural inhibition; and parental overprotectiveness. Precipitating life events: major stressful events (bereavement, relationship breakdown, assault), caffeine intoxication (5+ cups daily substantially raises panic attack risk), cocaine and amphetamine use, and medical conditions that produce similar physiological symptoms (hyperthyroidism, cardiac arrhythmias, hypoglycaemia, phaeochromocytoma) must all be excluded.

A panic attack is a discrete episode of intense fear or discomfort reaching peak intensity within minutes (typically 10 minutes, resolving within 20-30 minutes without treatment) with at least 4 of 13 defined symptoms: somatic symptoms — palpitations or pounding heart (the most common and distressing symptom, often prompting ED attendance for cardiac assessment); sweating; trembling or shaking; shortness of breath or smothering sensation; feeling of choking (globus sensation); chest pain or tightness; nausea or abdominal discomfort; dizziness, unsteadiness, or faintness; chills or hot flushes; and paraesthesia (numbness or tingling, especially circumoral and in the hands). Cognitive symptoms (the symptoms most distressing to patients and most diagnostic of panic disorder): derealisation (surroundings feel unreal, strange, or dream-like) or depersonalisation (feeling detached from oneself — 'out-of-body' experience); fear of losing control or going crazy; and fear of dying (typically fear of sudden cardiac death or stroke). Panic disorder (DSM-5 criteria): recurrent unexpected panic attacks — not all occurring in response to recognisable triggers — plus at least one month of either persistent anticipatory worry about additional attacks or their consequences, or significant maladaptive behavioural changes to avoid attacks (for example, avoiding exercise that raises heart rate, avoiding caffeine, avoiding leaving home alone, or always carrying a mobile phone or medication). Panic attacks occurring exclusively in the context of other conditions (social anxiety, specific phobia, PTSD) are contextual panic attacks and do not constitute panic disorder.

Panic disorder is a clinical diagnosis based on DSM-5 criteria — no laboratory test or imaging confirms it. However, medical conditions that cause or closely mimic panic attacks must be systematically excluded before making the psychiatric diagnosis, particularly given the cardiac and respiratory symptoms that dominate the presentation. ECG: essential to exclude paroxysmal supraventricular tachycardia (PSVT), atrial fibrillation, Wolf-Parkinson-White syndrome, and long QT syndrome, all of which can produce palpitations with autonomic symptoms indistinguishable from panic attacks during an episode. 24-48 hour Holter monitor or event recorder if the ECG is normal but palpitations are episodic and predominant. Thyroid function tests (TSH and free T4): hyperthyroidism (Graves' disease, toxic nodule) causes anxiety, palpitations, tremor, sweating, and heat intolerance — closely mimicking panic disorder and must be excluded at first presentation. Blood glucose: hypoglycaemia produces sympathomimetic symptoms (palpitations, sweating, tremor, confusion) that are indistinguishable from panic attacks; check fasting glucose and HbA1c. 24-hour urinary catecholamines or plasma metanephrines: if hypertension is present alongside panic attacks — to exclude phaeochromocytoma (adrenal catecholamine-secreting tumour). Full blood count: iron-deficiency anaemia causing tachycardia and palpitations. Echocardiogram if clinically indicated (atypical chest pain, murmur on examination). Validated severity measure: Panic Disorder Severity Scale (PDSS) — 7-item clinician-rated scale (0-4 per item, maximum 28) quantifying frequency, distress, agoraphobic avoidance, and functional impairment; guides treatment and monitors response. Diagnostic delay for panic disorder averages 5-7 years — a combination of patient reluctance to seek mental health help and clinician focus on excluding cardiac causes delays the definitive diagnosis.

Cognitive Behavioral Therapy (CBT): the most effective single treatment — includes psychoeducation, cognitive restructuring of catastrophic misinterpretations, interoceptive exposure (deliberate induction of feared sensations), and situational exposure for agoraphobia. Pharmacotherapy: SSRIs (sertraline, escitalopram, paroxetine) and SNRIs (venlafaxine) are first-line medications — allow 4-8 weeks for full response at therapeutic doses. Benzodiazepines provide rapid relief but should not be used long-term due to tolerance and dependence. Combined CBT and SSRI is superior to either alone for agoraphobic avoidance. Regular monitoring of treatment response, early detection of side effects, and ongoing assessment of disease progression are essential components of optimising patient outcomes over the long term. Treatment plans should be proactively reviewed and appropriately adjusted based on clinical response, patient-reported tolerability, changing patient circumstances, and continuously evolving evidence-based clinical guidelines. Meaningful shared decision-making between patients and their healthcare team, incorporating patient values and treatment preferences, consistently improves both treatment adherence and long-term outcomes.

Agoraphobia (ICD-11/DSM-5 — fear and avoidance of situations where escape seems difficult or help unavailable if a panic attack occurs) develops in 30-50% of patients with panic disorder, often progressively worsening over months to years of untreated illness; the spectrum ranges from avoiding driving on motorways or using public transport, to avoiding shopping centres and crowded places, to complete housebound agoraphobia requiring another person to accompany the patient at all times outside the home — the most severely disabling presentation of panic disorder. Major depressive disorder co-occurs in 50-65% of panic disorder patients — a bidirectional relationship — depression amplifies panic attack frequency and the functional disability of panic disorder exacerbates depression. Suicide risk is elevated in comorbid panic disorder and depression (lifetime suicidal ideation in approximately 25% of patients with panic disorder, significantly higher than in depression alone without panic). Substance use disorders (alcohol and benzodiazepine misuse as self-medication for anxiety): alcohol reliably suppresses panic in the short term but causes rebound anxiety and increased panic frequency on withdrawal, leading to dependence; benzodiazepine tolerance develops within 2-4 weeks. High healthcare utilisation and economic cost from repeated emergency department attendances (averaging 12 ED visits before psychiatric diagnosis) and extensive cardiology, respiratory, and neurology investigations for misattributed somatic symptoms. Occupational impairment (30-40% report significant work disability), reduced quality of life, relationship breakdown, and social isolation from progressive agoraphobic restriction.

Reduce caffeine consumption: caffeine at doses above 400 mg per day (4 cups of regular coffee) significantly lowers the panic attack threshold by antagonising adenosine receptors and increasing noradrenergic arousal — eliminating or substantially reducing caffeine intake is the most practical self-management intervention and often reduces attack frequency within days; this should be the first lifestyle advice given at diagnosis. Limit alcohol intake: while alcohol acutely suppresses anxiety, it causes rebound sympathetic activation during metabolism and withdrawal (particularly overnight and in the morning) that reliably triggers panic attacks — even moderate regular alcohol consumption perpetuates panic disorder. Regular aerobic exercise (30 minutes of moderate-intensity exercise 3-5 times per week) reduces anxiety sensitivity (the belief that bodily symptoms of arousal are harmful), improves HRV and autonomic balance, and is comparable to SSRIs in moderate anxiety severity. Early treatment initiation prevents progression to agoraphobia: every month of untreated panic disorder with avoidance behaviour increases the risk and severity of agoraphobia — beginning CBT (particularly interoceptive exposure) early before avoidance patterns become entrenched is the most effective preventive intervention against disability. Maintain SSRI treatment for at least 12-18 months after symptom remission — premature discontinuation (before 12 months) is the most common cause of relapse; taper slowly (over 4-8 weeks minimum) when stopping. Continue CBT skills practice (panic diary, interoceptive exposure exercises, cognitive restructuring) actively throughout the maintenance period — ongoing practice sustains recovery and prevents relapse.

Call emergency services if: you experience chest pain with radiation to the arm or jaw, particularly in someone over 40 or with cardiac risk factors — panic and heart attack symptoms overlap and a cardiac cause must be excluded. Go to A&E for a first-ever episode of severe chest pain, palpitations, or difficulty breathing if you have never been told your heart is normal — ECG and cardiac enzymes exclude acute coronary syndrome before a functional/anxiety cause is assumed. See your GP within 2 weeks if: you have had two or more unexpected episodes of intense fear with physical symptoms (pounding heart, breathlessness, dizziness, shaking) that come on without warning and peak within minutes — this clinical picture warrants formal assessment for panic disorder, including thyroid function, blood glucose, and ECG to exclude medical causes. Seek prompt mental health referral if: panic attacks are causing you to avoid leaving home, using public transport, or attending work — agoraphobic avoidance, once established, becomes progressively harder to treat. Early CBT referral, before avoidance is entrenched, produces the best long-term outcomes.