Panic disorder

Panic disorder is an anxiety disorder characterized by recurrent unexpected panic attacks accompanied by persistent concern about future attacks or their consequences and/or maladaptive behavioural changes aimed at avoiding further attacks. A panic attack is a sudden episode of intense fear or discomfort that reaches its peak within minutes and is associated with prominent physical and psychological symptoms.

Epidemiology

• Panic disorder commonly begins in late adolescence or early adulthood

• Females are affected more frequently than males

• It frequently coexists with other anxiety disorders depression and substance use disorders

• Early recognition and treatment improve long-term outcomes

Risk Factors

• Family history of panic disorder or other anxiety disorders

• Previous panic attacks

• Chronic psychological stress

• History of childhood trauma or adverse life events

• Personality traits such as high anxiety sensitivity

• Depression or other psychiatric disorders

• Excessive caffeine stimulant or recreational drug use

• Certain medical conditions including hyperthyroidism and cardiac arrhythmias

Pathophysiology

Panic disorder results from dysregulation of neural circuits involved in fear processing including the amygdala hippocampus prefrontal cortex and brainstem. Abnormalities in serotonergic noradrenergic and gamma-aminobutyric acid (GABA) neurotransmission contribute to increased sensitivity to internal bodily sensations and exaggerated fear responses. Genetic predisposition and environmental stressors interact to increase vulnerability.

Clinical Presentation

Panic attack

Symptoms typically develop suddenly peak within approximately 10 minutes and usually resolve within 20–30 minutes

Psychological symptoms

• Intense fear or terror

• Sense of impending doom or death

• Feeling of losing control or "going crazy"

• Feeling detached from oneself or surroundings

Physical symptoms

• Palpitations or rapid heartbeat

• Chest discomfort

• Shortness of breath or sensation of choking

• Sweating

• Trembling or shaking

• Dizziness or light-headedness

• Nausea or abdominal discomfort

• Chills or hot flushes

• Paresthesia

• Feeling faint

Features suggestive of panic disorder

• Recurrent unexpected panic attacks

• Persistent fear of future attacks

• Avoidance of situations associated with previous attacks

• Functional impairment in social occupational or daily activities

Diagnostic Criteria

Diagnosis is clinical and based on the presence of:

• Recurrent unexpected panic attacks

• At least one attack followed by one month or more of one or both of the following:

  • Persistent concern or worry about additional panic attacks or their consequences

  • Significant maladaptive behavioural change related to the attacks

• Symptoms are not attributable to substance use another medical condition or another mental disorder

Differential Diagnosis

• Generalized anxiety disorder

• Social anxiety disorder

• Specific phobia

• Major depressive disorder with anxiety

• Hyperthyroidism

• Cardiac arrhythmias

• Acute coronary syndrome

• Asthma

• Pulmonary embolism

• Hypoglycaemia

• Substance intoxication or withdrawal

• Phaeochromocytoma

Investigations

Investigations are aimed at excluding underlying medical conditions when clinically indicated

• Complete history and physical examination

• Blood glucose

• Thyroid function tests if hyperthyroidism is suspected

• Electrocardiogram if cardiac disease is suspected

• Full blood count where indicated

• Serum electrolytes if clinically indicated

• Toxicology screening when substance misuse is suspected

Management

Treatment goals

• Control acute panic symptoms

• Exclude serious medical causes

• Reduce frequency and severity of panic attacks

• Improve quality of life and functional status

• Prevent relapse

Non-Pharmacological Management

• Provide psychoeducation about panic disorder

• Reassure the patient that symptoms are real but not life-threatening after serious medical causes have been excluded

• Encourage slow controlled breathing during panic attacks

• Identify and reduce triggers where possible

• Offer cognitive behavioural therapy as first-line psychological treatment

• Promote stress management techniques and relaxation exercises

• Encourage regular physical activity and adequate sleep

• Advise reduction or avoidance of caffeine alcohol nicotine and recreational drugs

• Treat coexisting psychiatric disorders

Pharmacological Management

Acute panic attack

Diazepam

• Route: Oral

• Dose: 5–10 mg

• Frequency: Every 12 hours

• Duration: Short-term until symptoms are controlled

• Notes:

  • Titrate according to clinical response

  • Use the lowest effective dose

  • Avoid prolonged use because of dependence risk

OR

Lorazepam

• Route: Oral

• Dose: 2–4 mg

• Frequency: Every 12 hours

• Duration: Short-term until symptoms are controlled

• Notes:

  • Titrate according to symptom resolution

  • Use cautiously in older adults and patients with respiratory impairment

OR

Clonazepam

• Route: Oral

• Dose: 0.5–3 mg

• Frequency: Every 12 hours

• Duration: Short-term until symptoms are controlled

• Notes:

  • Titrate according to symptom resolution

  • Monitor for sedation dependence and withdrawal symptoms

Long-term treatment of panic disorder

Amitriptyline

• Route: Oral

• Dose: 25–75 mg

• Frequency: Once daily at night

• Duration: Initially 6–12 months after symptom control

• Notes:

  • Start with a low dose and increase gradually according to tolerability

  • Monitor for anticholinergic adverse effects sedation and cardiovascular effects

  • Use with caution in older adults and patients with cardiovascular disease

OR

Citalopram

• Route: Oral

• Dose: 10–40 mg

• Frequency: Once daily

• Duration: Initially 6–12 months after symptom control

• Notes:

  • Start with a low dose and titrate gradually

  • Monitor for QT interval prolongation particularly at higher doses or in high-risk patients

  • Clinical improvement may take several weeks

OR

Fluoxetine

• Route: Oral

• Dose: 20–40 mg

• Frequency: Once daily

• Duration: Initially 6–12 months after symptom control

• Notes:

  • Start with a low dose and titrate gradually

  • Therapeutic benefit may take several weeks

  • Monitor for increased anxiety during the initial treatment period

Additional Notes

• Consider short-term co-administration of a benzodiazepine during initiation of antidepressant therapy because antidepressants have a delayed onset of action and may transiently worsen anxiety

• Benzodiazepines should generally not be continued beyond 4–6 weeks because of the risk of tolerance dependence and withdrawal

• Long-term pharmacotherapy may be required in patients with recurrent disease

• Relapse may occur after discontinuation of treatment therefore medicines should be tapered gradually rather than stopped abruptly

Referral Criteria

Refer to the next level of care if:

• Symptoms remain uncontrolled despite adequate treatment

• Benzodiazepine therapy is required beyond 6 weeks

• Diagnosis is uncertain

• Severe functional impairment is present

• Significant psychiatric comorbidity is suspected

• Suicidal ideation or self-harm risk is present

• Psychotic symptoms develop

• Severe depression coexists

• Serious underlying medical illness is suspected

Complications

• Agoraphobia

• Depression

• Substance misuse

• Social isolation

• Occupational impairment

• Reduced quality of life

• Increased healthcare utilization

• Suicide risk particularly in patients with comorbid depression

Prevention

• Early recognition and treatment of anxiety symptoms

• Timely management of psychosocial stressors

• Treatment of comorbid psychiatric disorders

• Limitation of caffeine alcohol and stimulant use

• Regular exercise healthy sleep and stress reduction strategies

• Adherence to prescribed treatment and follow-up appointments

Prognosis

• Most patients improve with appropriate psychological therapy pharmacotherapy or a combination of both

• Relapses are common particularly after premature discontinuation of treatment

• Long-term outcomes are improved by adherence to treatment regular follow-up and management of comorbid conditions

Patient Education

• Panic disorder is a treatable medical condition

• Panic attacks are frightening but are not usually life-threatening once serious medical conditions have been excluded

• Take prescribed medicines exactly as directed

• Do not stop antidepressants or benzodiazepines abruptly without medical advice

• Avoid excessive caffeine alcohol nicotine and recreational drugs

• Learn breathing and relaxation techniques to help manage acute symptoms

• Attend psychotherapy sessions if available

• Seek immediate medical attention if symptoms suggest another serious medical condition such as persistent chest pain loss of consciousness severe shortness of breath or suicidal thoughts