About This Page
This is a clinician-written, evidence-based guide aligned to the MCC Examination Objectives. It is structured by clinical presentation — the way the MCCQE tests and the way patients actually present. Management reflects current Canadian guidelines (CMA, CFPC, CPS). Always cross-reference with institutional protocols and clinical judgment.
The Bottom Line
- Anxiety is a symptom cluster: first exclude ACS, PE, arrhythmia, thyrotoxicosis, hypoglycaemia, intoxication, withdrawal, psychosis, mania, and suicidality
- Panic attacks are abrupt surges of fear with somatic symptoms; panic disorder requires recurrent unexpected attacks plus persistent concern or behavioural change
- GAD is excessive worry across domains with tension, sleep disturbance, irritability, poor concentration, and functional impairment
- First-line long-term treatment is CBT and/or SSRI/SNRI; benzodiazepines are short-term rescue only and should be avoided in high-risk groups
- Medical mimic recognition is high yield: palpitations, dyspnea, tremor, weight loss, syncope, chest pain, and abnormal vitals require investigation before diagnosing panic
Approach to the Presentation
Anxiety presentations commonly arrive in primary care, walk-in clinics, emergency departments, and student health settings. A safe approach begins by deciding whether the patient is medically stable and whether the anxiety is primary or secondary. Ask about onset, triggers, panic attacks, worry domains, avoidance, compulsions, trauma exposure, substances, caffeine/energy drinks, prescribed stimulants, corticosteroids, cannabis, alcohol withdrawal, and suicide risk. Perform focused physical assessment including vitals, cardiopulmonary examination, thyroid signs, neurological signs, and signs of intoxication or withdrawal. Once dangerous causes are excluded, classify the likely anxiety disorder and agree a stepped plan that includes psychoeducation, CBT principles, sleep and substance interventions, and medication when impairment is persistent or severe.
Differential Diagnosis
| diagnosis | likelihood | key features | distinguishing test |
|---|---|---|---|
| ACS / pulmonary embolism / arrhythmia | must-not-miss | Chest pain, dyspnea, syncope, hypoxia, tachyarrhythmia, risk factors, exertional symptoms, abnormal ECG or vitals | ECG, troponin, oxygen saturation, Wells/PERC/D-dimer/CTPA as indicated |
| Thyrotoxicosis or metabolic disorder | must-not-miss | Weight loss, tremor, heat intolerance, diarrhoea, menstrual change, lid lag, tachycardia; consider hypoglycaemia and pheochromocytoma if episodic severe symptoms | TSH/free T4, capillary glucose; targeted endocrine work-up if red flags |
| Substance intoxication or withdrawal | must-not-miss | Stimulants, caffeine, cannabis, cocaine, amphetamines, alcohol withdrawal, benzodiazepine withdrawal, opioid withdrawal; autonomic signs prominent | Substance history, medication reconciliation, collateral, urine toxicology when helpful |
| Mania / mixed affective state | must-not-miss | Anxiety with decreased need for sleep, increased energy, pressured speech, irritability, impulsivity, grandiosity, racing thoughts | Mental status exam + longitudinal mood history; collateral strongly recommended |
| Panic disorder | common | Recurrent unexpected panic attacks with abrupt onset, palpitations, dyspnea, chest tightness, trembling, derealisation, fear of dying, followed by avoidance or worry | Clinical DSM-5-TR diagnosis after ruling out medical causes |
| Generalised anxiety disorder | common | Excessive worry across multiple domains for months, restlessness, muscle tension, fatigue, poor concentration, irritability, insomnia | GAD-7 for severity; clinical diagnosis based on worry pattern and impairment |
| Social anxiety disorder / specific phobia | common | Fear and avoidance of social scrutiny or specific stimuli; anticipatory anxiety; insight usually preserved | Trigger-specific history and functional impairment |
| PTSD / acute stress disorder | less common | Intrusions, nightmares, hypervigilance, avoidance, negative cognitions after trauma | Trauma-informed history; PTSD screen |
| Obsessive-compulsive disorder | less common | Intrusive unwanted obsessions and repetitive compulsions performed to reduce distress; time-consuming and ego-dystonic | Y-BOCS or focused obsession/compulsion history |
Red Flags & Key History
Symptoms
Chest pain, syncope, exertional symptoms, hypoxia, hemoptysis, or unilateral leg swelling
New anxiety after age 40 without psychiatric history
Suicidal ideation, self-harm, severe hopelessness, or inability to function
Decreased need for sleep with increased energy or risky behaviour
Severe autonomic instability, confusion, hallucinations, or seizures
Abrupt waves peaking within minutes with fear of dying
Worry across finances, health, family, work, and minor matters
Avoidance of social performance or feared situations
Signs
Abnormal vital signs: fever, hypoxia, persistent tachycardia, hypotension, severe hypertension
Thyromegaly, lid lag, tremor, hyperreflexia
Intoxication or withdrawal signs: diaphoresis, tremor, mydriasis, agitation
Psychosis, disorganisation, pressured speech, or marked psychomotor agitation
Normal cardiopulmonary examination and normal vitals after panic episode
Approach to Investigation
First-line
Vitals, oxygen saturation, focused physical examinationPersistent tachycardia, hypoxia, fever, hypotension, or severe hypertension should prompt medical evaluation rather than diagnostic closure on anxiety
ECG when palpitations, chest pain, syncope, stimulant use, older age, or cardiac riskRules out arrhythmia, ischemia, QT prolongation, pre-excitation, or drug effects
Targeted labsTSH, CBC, glucose, electrolytes, pregnancy test, and toxicology only when suggested by history/exam
GAD-7 / panic severity / functional assessmentUseful for baseline severity and monitoring but not diagnostic in isolation
Second-line
Trauma, OCD, and substance screensUse when symptoms suggest PTSD, OCD, alcohol/cannabis/stimulant use, or sedative withdrawal
Collateral historyHelpful for mania, psychosis, substance use, domestic violence, or safety concerns
Specialist
Psychiatry referralSevere impairment, suicidality, psychosis, mania, treatment resistance, diagnostic uncertainty, pregnancy/postpartum high risk, or complex comorbidity
CBT / exposure-based therapy referralFirst-line for panic disorder, phobias, social anxiety, OCD, PTSD, and GAD where available
Management Principles
Canadian Anxiety Guidelines (CANMAT-linked expert consensus) + CAMH clinical resources + DSM-5-TR1
If medically unstable or red flags present
- Treat as medical until proven otherwise: ABCs, ECG, oxygen saturation, glucose, targeted labs and imaging
- Manage intoxication/withdrawal or toxidrome according to the substance involved
- If suicidality, psychosis, mania, or severe agitation: urgent psychiatric/crisis assessment
2
Psychoeducation and behavioural treatment
- Explain the anxiety cycle and the role of avoidance; validate symptoms without implying they are imagined
- CBT, exposure therapy, relaxation/breathing skills, sleep regularity, reduction of caffeine/energy drinks/cannabis, and graded return to avoided activities
- For panic: teach that symptoms peak and pass; interoceptive exposure is more effective than repeated reassurance-seeking once medical causes are excluded
3
Medication for persistent or moderate-severe anxiety
- SSRIs or SNRIs are first-line for many anxiety disorders: start low, go slow, warn about transient activation and GI upset
- Avoid chronic benzodiazepines; if used, keep short-term, lowest effective dose, clear stop plan, and avoid in substance use disorder, older adults, sleep apnoea, pregnancy where possible, or concurrent opioids
Complications & Pitfalls
- Diagnosing panic before ruling out danger: PE, ACS, arrhythmia, thyrotoxicosis, hypoglycaemia, stimulant intoxication, and withdrawal can all look like panic.
- Creating benzodiazepine dependence: Long-term benzodiazepines worsen avoidance, cognition, falls risk, and substance-related harm.
- Missing mania: Anxiety plus decreased need for sleep and increased energy is not simple GAD.
- Reassurance-seeking loop: Repeated ED tests after adequate exclusion can maintain panic and health anxiety.
MCCQE1 Exam Tips
- 1An older patient with new panic-like symptoms needs medical work-up before psychiatric closure
- 2Anxiety with chest pain, syncope, abnormal vitals, or hypoxia needs medical assessment, not reflex lorazepam
- 3For chronic GAD or panic disorder, SSRIs/SNRIs and CBT are preferred; benzodiazepines are not first-line long-term treatment
- 4Ask about caffeine, cannabis, cocaine/amphetamines, alcohol withdrawal, prescribed stimulants, decongestants, and steroids
- 5Panic disorder requires concern/avoidance after attacks; a single panic attack during stress is not automatically panic disorder
- 6Use CanMEDS communication: validate symptoms while explaining the mind-body cycle
practicetest your knowledge on anxietyApply what you've learnt with MCCQE1-style questions from the iatroX Q-Bank — psychiatric and beyond.
open q-bank