2026 UPDATED QUESTIONS DOWNLOAD
MCCQE1 Exam MEGA Bank (350 Q&As) | 2024-2026 Updated |
CDM & MCQ Format | Medical Council of Canada Qualifying
Examination Part I | Verified Rationales
Stop stressing over the MCCQE1 and start studying the right material.
The Medical Council of Canada Qualifying Examination (MCCQE) Part I is the high-stakes
gateway to residency in Canada. It tests not just your medical knowledge, but your Clinical
Decision-Making (CDM) skills. This 350-Question MEGA Bank is specifically designed to
align with the MCC Objectives and the "Canadian way" of practicing medicine.
Each question is formatted with a professional-level stem, plausible distractors, and
a detailed rationale in italics to explain the clinical logic, gold-standard guidelines, and
Canadian ethical standards behind the correct answer.
1. A 45-year-old female presents with a 2-month history of symmetric joint pain in her
hands, specifically the proximal interphalangeal (PIP) and metacarpophalangeal (MCP)
joints. She reports stiffness lasting over an hour every morning. What is the most
specific initial laboratory test to confirm the diagnosis?
A) Rheumatoid Factor (RF)
B) Anti-Cyclic Citrullinated Peptide (Anti-CCP) Antibodies
C) Erythrocyte Sedimentation Rate (ESR)
D) Antinuclear Antibody (ANA)
Correct Answer: B
Rationale: While Rheumatoid Factor is sensitive, Anti-CCP is highly specific for Rheumatoid
Arthritis (RA). ESR is a non-specific marker of inflammation, and ANA is more associated with
SLE.
2. A 3-week-old male infant presents with non-bilious projectile vomiting after every
feeding. On examination, a small, firm mass is palpable in the right upper quadrant.
What is the initial diagnostic imaging of choice?
A) Abdominal X-ray
B) Abdominal Ultrasound
C) Upper GI Barium Swallow
, 2026 UPDATED QUESTIONS DOWNLOAD
D) CT Abdomen
Correct Answer: B
Rationale: The presentation is classic for Hypertrophic Pyloric Stenosis. Ultrasound is the gold
standard for measuring pyloric muscle thickness and length to confirm the diagnosis without
radiation.
3. A 29-year-old G2P1 at 38 weeks gestation presents to the birthing unit with sudden,
painful vaginal bleeding and a firm, tender uterus. The fetal heart rate monitor shows
late decelerations. What is the most likely diagnosis?
A) Placenta Previa
B) Vasa Previa
C) Placental Abruption
D) Uterine Rupture
Correct Answer: C
Rationale: Painful vaginal bleeding in the third trimester associated with uterine tenderness
and fetal distress is pathognomonic for Placental Abruption. Placenta previa is typically
painless.
4. A 68-year-old male with a history of smoking presents with painless gross hematuria.
He denies any recent trauma or urinary tract infections. What is the most appropriate
next step in investigation?
A) Renal Ultrasound
B) Urine Culture and Sensitivity
C) Cystoscopy and CT Urogram
D) Recheck urine in 2 weeks
Correct Answer: C
Rationale: Painless gross hematuria in an older smoker must be considered bladder or renal
cell carcinoma until proven otherwise. Cystoscopy is required to visualize the bladder, and CT
Urogram evaluates the upper urinary tract.
5. A 19-year-old college student is brought to the health clinic. She has lost 15% of her
body weight in 3 months, has fine hair (lanugo) on her back, and says she "feels fat"
despite a BMI of 16. What is the most common electrolyte abnormality associated with
refeeding syndrome in this patient?
A) Hyperkalemia
B) Hypophosphatemia
C) Hypermagnesemia
D) Hyponatremia
Correct Answer: B
Rationale: Refeeding syndrome occurs when nutritional support is restarted in a severely
malnourished patient. The surge in insulin causes an intracellular shift of phosphorus, leading
to severe hypophosphatemia, which can cause cardiac failure.
, 2026 UPDATED QUESTIONS DOWNLOAD
6. A 55-year-old male presents with sudden onset of "the worst headache of my life." He
is photophobic and has neck stiffness. A CT scan of the head without contrast is
negative. What is the next best step?
A) Repeat CT with contrast
B) Lumbar Puncture (LP)
C) MRI Head
D) Discharge with migraine medication
Correct Answer: B
Rationale: If Subarachnoid Hemorrhage (SAH) is suspected and the CT is negative, a Lumbar
Puncture is mandatory to look for xanthochromia or RBCs that do not clear in successive
tubes.
7. In a patient with chronic obstructive pulmonary disease (COPD), which of the
following interventions has been proven to decrease mortality?
A) Inhaled Corticosteroids
B) Long-acting Beta-agonists (LABA)
C) Long-term Oxygen Therapy (LTOT)
D) Yearly Flu Vaccination
Correct Answer: C
Rationale: LTOT (for patients with resting PaO2 < 55 mmHg) and smoking cessation are the
only two interventions proven to extend life in COPD patients. Vaccinations reduce morbidity
but LTOT is the primary life-prolonging therapy.
8. A 24-year-old female presents with a 1-week history of low mood, insomnia, and
suicidal ideation. She reports that 2 months ago, she spent $5,000 on a vacation she
couldn't afford and didn't sleep for 4 days because she felt "on top of the world." What
is the most appropriate first-line treatment?
A) Fluoxetine (SSRI)
B) Lithium or Valproate
C) Cognitive Behavioral Therapy (CBT) alone
D) Lorazepam (Benzodiazepine)
Correct Answer: B
Rationale: The patient describes a manic episode followed by a depressive episode, consistent
with Bipolar I Disorder. Mood stabilizers like Lithium or Valproate are first-line. Monotherapy
with antidepressants (SSRIs) can trigger a switch into mania.
9. A 72-year-old woman is found confused on the floor of her apartment. Labs show:
Sodium 160 mmol/L, Serum Osmolality 340 mOsm/kg, and Urine Osmolality 100
mOsm/kg. What is the most likely diagnosis?
A) SIADH
B) Diabetes Insipidus
C) Primary Polydipsia
, 2026 UPDATED QUESTIONS DOWNLOAD
D) Dehydration from poor intake
Correct Answer: B
Rationale: High serum sodium and osmolality combined with inappropriately dilute urine (low
urine osmolality) is diagnostic of Diabetes Insipidus.
10. A 50-year-old female with a history of mechanical heart valve replacement presents
for a dental extraction. What is the current Canadian guideline regarding antibiotic
prophylaxis?
A) No prophylaxis is required.
B) Amoxicillin 2g PO one hour before the procedure.
C) Penicillin V for 7 days post-procedure.
D) Clindamycin 600mg only if she has a fever.
Correct Answer: B
Rationale: Patients with prosthetic heart valves are at high risk for Infective Endocarditis. For
dental procedures involving gingival manipulation, Amoxicillin 2g (or Clindamycin if allergic) is
recommended.
11. A 32-year-old male is found unconscious in an alley. His pupils are pinpoint, and his
respiratory rate is 6 breaths/min. What is the most appropriate initial treatment?
A) Flumazenil
B) Naloxone
C) IV Dextrose
D) Intubation and ventilation
Correct Answer: B
Rationale: The triad of coma, pinpoint pupils, and respiratory depression is highly suggestive of
opioid overdose. Naloxone is the immediate life-saving antagonist.
12. A 30-year-old G1P0 at 10 weeks gestation presents for her first prenatal visit. She
has a history of a sibling with a neural tube defect. What is the recommended daily dose
of folic acid for her?
A) 0.4 mg
B) 1.0 mg
C) 4.0 mg
D) 10.0 mg
Correct Answer: C
Rationale: For "high-risk" patients (personal or family history of NTD), SOGC guidelines
recommend 4.0 mg of folic acid daily, starting 3 months prior to conception through the first
trimester.
13. A 60-year-old male presents with fatigue and weight loss. CBC shows: Hemoglobin
90 g/L, MCV 72 fL. Fecal occult blood test is positive. What is the most likely cause of
his anemia?
A) Vitamin B12 deficiency
MCCQE1 Exam MEGA Bank (350 Q&As) | 2024-2026 Updated |
CDM & MCQ Format | Medical Council of Canada Qualifying
Examination Part I | Verified Rationales
Stop stressing over the MCCQE1 and start studying the right material.
The Medical Council of Canada Qualifying Examination (MCCQE) Part I is the high-stakes
gateway to residency in Canada. It tests not just your medical knowledge, but your Clinical
Decision-Making (CDM) skills. This 350-Question MEGA Bank is specifically designed to
align with the MCC Objectives and the "Canadian way" of practicing medicine.
Each question is formatted with a professional-level stem, plausible distractors, and
a detailed rationale in italics to explain the clinical logic, gold-standard guidelines, and
Canadian ethical standards behind the correct answer.
1. A 45-year-old female presents with a 2-month history of symmetric joint pain in her
hands, specifically the proximal interphalangeal (PIP) and metacarpophalangeal (MCP)
joints. She reports stiffness lasting over an hour every morning. What is the most
specific initial laboratory test to confirm the diagnosis?
A) Rheumatoid Factor (RF)
B) Anti-Cyclic Citrullinated Peptide (Anti-CCP) Antibodies
C) Erythrocyte Sedimentation Rate (ESR)
D) Antinuclear Antibody (ANA)
Correct Answer: B
Rationale: While Rheumatoid Factor is sensitive, Anti-CCP is highly specific for Rheumatoid
Arthritis (RA). ESR is a non-specific marker of inflammation, and ANA is more associated with
SLE.
2. A 3-week-old male infant presents with non-bilious projectile vomiting after every
feeding. On examination, a small, firm mass is palpable in the right upper quadrant.
What is the initial diagnostic imaging of choice?
A) Abdominal X-ray
B) Abdominal Ultrasound
C) Upper GI Barium Swallow
, 2026 UPDATED QUESTIONS DOWNLOAD
D) CT Abdomen
Correct Answer: B
Rationale: The presentation is classic for Hypertrophic Pyloric Stenosis. Ultrasound is the gold
standard for measuring pyloric muscle thickness and length to confirm the diagnosis without
radiation.
3. A 29-year-old G2P1 at 38 weeks gestation presents to the birthing unit with sudden,
painful vaginal bleeding and a firm, tender uterus. The fetal heart rate monitor shows
late decelerations. What is the most likely diagnosis?
A) Placenta Previa
B) Vasa Previa
C) Placental Abruption
D) Uterine Rupture
Correct Answer: C
Rationale: Painful vaginal bleeding in the third trimester associated with uterine tenderness
and fetal distress is pathognomonic for Placental Abruption. Placenta previa is typically
painless.
4. A 68-year-old male with a history of smoking presents with painless gross hematuria.
He denies any recent trauma or urinary tract infections. What is the most appropriate
next step in investigation?
A) Renal Ultrasound
B) Urine Culture and Sensitivity
C) Cystoscopy and CT Urogram
D) Recheck urine in 2 weeks
Correct Answer: C
Rationale: Painless gross hematuria in an older smoker must be considered bladder or renal
cell carcinoma until proven otherwise. Cystoscopy is required to visualize the bladder, and CT
Urogram evaluates the upper urinary tract.
5. A 19-year-old college student is brought to the health clinic. She has lost 15% of her
body weight in 3 months, has fine hair (lanugo) on her back, and says she "feels fat"
despite a BMI of 16. What is the most common electrolyte abnormality associated with
refeeding syndrome in this patient?
A) Hyperkalemia
B) Hypophosphatemia
C) Hypermagnesemia
D) Hyponatremia
Correct Answer: B
Rationale: Refeeding syndrome occurs when nutritional support is restarted in a severely
malnourished patient. The surge in insulin causes an intracellular shift of phosphorus, leading
to severe hypophosphatemia, which can cause cardiac failure.
, 2026 UPDATED QUESTIONS DOWNLOAD
6. A 55-year-old male presents with sudden onset of "the worst headache of my life." He
is photophobic and has neck stiffness. A CT scan of the head without contrast is
negative. What is the next best step?
A) Repeat CT with contrast
B) Lumbar Puncture (LP)
C) MRI Head
D) Discharge with migraine medication
Correct Answer: B
Rationale: If Subarachnoid Hemorrhage (SAH) is suspected and the CT is negative, a Lumbar
Puncture is mandatory to look for xanthochromia or RBCs that do not clear in successive
tubes.
7. In a patient with chronic obstructive pulmonary disease (COPD), which of the
following interventions has been proven to decrease mortality?
A) Inhaled Corticosteroids
B) Long-acting Beta-agonists (LABA)
C) Long-term Oxygen Therapy (LTOT)
D) Yearly Flu Vaccination
Correct Answer: C
Rationale: LTOT (for patients with resting PaO2 < 55 mmHg) and smoking cessation are the
only two interventions proven to extend life in COPD patients. Vaccinations reduce morbidity
but LTOT is the primary life-prolonging therapy.
8. A 24-year-old female presents with a 1-week history of low mood, insomnia, and
suicidal ideation. She reports that 2 months ago, she spent $5,000 on a vacation she
couldn't afford and didn't sleep for 4 days because she felt "on top of the world." What
is the most appropriate first-line treatment?
A) Fluoxetine (SSRI)
B) Lithium or Valproate
C) Cognitive Behavioral Therapy (CBT) alone
D) Lorazepam (Benzodiazepine)
Correct Answer: B
Rationale: The patient describes a manic episode followed by a depressive episode, consistent
with Bipolar I Disorder. Mood stabilizers like Lithium or Valproate are first-line. Monotherapy
with antidepressants (SSRIs) can trigger a switch into mania.
9. A 72-year-old woman is found confused on the floor of her apartment. Labs show:
Sodium 160 mmol/L, Serum Osmolality 340 mOsm/kg, and Urine Osmolality 100
mOsm/kg. What is the most likely diagnosis?
A) SIADH
B) Diabetes Insipidus
C) Primary Polydipsia
, 2026 UPDATED QUESTIONS DOWNLOAD
D) Dehydration from poor intake
Correct Answer: B
Rationale: High serum sodium and osmolality combined with inappropriately dilute urine (low
urine osmolality) is diagnostic of Diabetes Insipidus.
10. A 50-year-old female with a history of mechanical heart valve replacement presents
for a dental extraction. What is the current Canadian guideline regarding antibiotic
prophylaxis?
A) No prophylaxis is required.
B) Amoxicillin 2g PO one hour before the procedure.
C) Penicillin V for 7 days post-procedure.
D) Clindamycin 600mg only if she has a fever.
Correct Answer: B
Rationale: Patients with prosthetic heart valves are at high risk for Infective Endocarditis. For
dental procedures involving gingival manipulation, Amoxicillin 2g (or Clindamycin if allergic) is
recommended.
11. A 32-year-old male is found unconscious in an alley. His pupils are pinpoint, and his
respiratory rate is 6 breaths/min. What is the most appropriate initial treatment?
A) Flumazenil
B) Naloxone
C) IV Dextrose
D) Intubation and ventilation
Correct Answer: B
Rationale: The triad of coma, pinpoint pupils, and respiratory depression is highly suggestive of
opioid overdose. Naloxone is the immediate life-saving antagonist.
12. A 30-year-old G1P0 at 10 weeks gestation presents for her first prenatal visit. She
has a history of a sibling with a neural tube defect. What is the recommended daily dose
of folic acid for her?
A) 0.4 mg
B) 1.0 mg
C) 4.0 mg
D) 10.0 mg
Correct Answer: C
Rationale: For "high-risk" patients (personal or family history of NTD), SOGC guidelines
recommend 4.0 mg of folic acid daily, starting 3 months prior to conception through the first
trimester.
13. A 60-year-old male presents with fatigue and weight loss. CBC shows: Hemoglobin
90 g/L, MCV 72 fL. Fecal occult blood test is positive. What is the most likely cause of
his anemia?
A) Vitamin B12 deficiency
