COMLEX Level 3 practice exam (Form
124) Exam With Actual 120 Questions
& Verified Answers,Plus
Rationales/Expert Verified For
Guaranteed Pass Graded A+/
2025/2026 /Latest Update/Instant
Download Pdf
1. A 45-year-old man presents with chest pain radiating to his left arm. ECG shows ST
elevation in leads II, III, and aVF. Which artery is most likely occluded?
A) Left anterior descending
B) Left circumflex
C) Right coronary
D) Posterior descending
C) Right coronary
Rationale: ST elevation in II, III, aVF indicates an inferior MI, usually due to right coronary
artery occlusion.
2. A 30-year-old woman presents with heat intolerance, weight loss, and palpitations.
Labs show low TSH and elevated free T4. Which is the most likely diagnosis?
A) Hypothyroidism
B) Graves’ disease
C) Hashimoto’s thyroiditis
D) Subacute thyroiditis
B) Graves’ disease
Rationale: Low TSH and high free T4 with hyperthyroid symptoms suggest primary
hyperthyroidism; Graves’ is the most common cause in this age group.
3. A 60-year-old man with COPD develops acute hypoxemia. Chest X-ray shows
hyperinflated lungs without infiltrates. What is the most likely cause?
A) Pulmonary embolism
, B) Pneumothorax
C) Acute bronchitis
D) Asthma exacerbation
B) Pneumothorax
Rationale: COPD patients are at risk for spontaneous pneumothorax, often presenting with
sudden dyspnea and hyperresonance on exam.
4. A 25-year-old woman has dysuria, frequency, and suprapubic pain. Urinalysis shows
positive leukocyte esterase and nitrites. Most appropriate treatment?
A) Ciprofloxacin
B) Nitrofurantoin
C) Amoxicillin
D) TMP-SMX
B) Nitrofurantoin
Rationale: Uncomplicated cystitis in women is commonly treated with nitrofurantoin;
avoid fluoroquinolones first-line due to resistance and side effects.
5. A 70-year-old man presents with difficulty initiating urination, weak stream, and
nocturia. PSA is normal. Most likely diagnosis?
A) Prostate cancer
B) BPH
C) Bladder cancer
D) Neurogenic bladder
B) BPH
Rationale: Symptoms of obstructive and irritative urinary issues in an older male with
normal PSA are classic for benign prostatic hyperplasia.
6. A 55-year-old woman with diabetes presents with right eye pain, redness, and vision
loss. Slit-lamp shows a corneal ulcer. Most likely organism?
A) Staphylococcus aureus
B) Pseudomonas aeruginosa
C) Streptococcus pneumoniae
D) Herpes simplex virus
B) Pseudomonas aeruginosa
Rationale: Contact lens wearers or diabetics are at risk for Pseudomonas keratitis, which
can rapidly cause corneal ulceration.
7. A 40-year-old man presents with fatigue, jaundice, and pruritus. Labs: ALT > AST,
positive ANA, anti-smooth muscle antibodies. Most likely diagnosis?
A) Primary biliary cholangitis
B) Autoimmune hepatitis
, C) Hepatitis C
D) Hemochromatosis
B) Autoimmune hepatitis
Rationale: Positive ANA and anti-smooth muscle antibodies with hepatocellular injury
indicate autoimmune hepatitis.
8. A 5-year-old boy presents with a barking cough and stridor. He is afebrile and in mild
respiratory distress. Most appropriate initial treatment?
A) Antibiotics
B) Racemic epinephrine
C) Corticosteroids
D) Oxygen
C) Corticosteroids
Rationale: Croup is usually viral; corticosteroids reduce airway inflammation. Racemic
epinephrine is for severe cases.
9. A 65-year-old man presents with sudden-onset weakness on the right side and
slurred speech. CT shows an ischemic stroke in the left MCA territory. Which artery
was occluded?
A) Left MCA
B) Right MCA
C) Left ACA
D) Right PCA
A) Left MCA
Rationale: Left MCA strokes cause right-sided weakness and aphasia if in the dominant
hemisphere.
10. A 28-year-old woman presents with fatigue, cold intolerance, weight gain, and dry
skin. Labs: TSH elevated, free T4 low. Most likely diagnosis?
A) Hyperthyroidism
B) Hashimoto’s thyroiditis
C) Subacute thyroiditis
D) Pituitary adenoma
B) Hashimoto’s thyroiditis
Rationale: Primary hypothyroidism with elevated TSH and low free T4 is typical of
Hashimoto’s thyroiditis.
11. A 55-year-old man presents with progressive shortness of breath and dry cough. CT
shows honeycombing at lung bases. Most likely diagnosis?
A) COPD
B) Pulmonary fibrosis
124) Exam With Actual 120 Questions
& Verified Answers,Plus
Rationales/Expert Verified For
Guaranteed Pass Graded A+/
2025/2026 /Latest Update/Instant
Download Pdf
1. A 45-year-old man presents with chest pain radiating to his left arm. ECG shows ST
elevation in leads II, III, and aVF. Which artery is most likely occluded?
A) Left anterior descending
B) Left circumflex
C) Right coronary
D) Posterior descending
C) Right coronary
Rationale: ST elevation in II, III, aVF indicates an inferior MI, usually due to right coronary
artery occlusion.
2. A 30-year-old woman presents with heat intolerance, weight loss, and palpitations.
Labs show low TSH and elevated free T4. Which is the most likely diagnosis?
A) Hypothyroidism
B) Graves’ disease
C) Hashimoto’s thyroiditis
D) Subacute thyroiditis
B) Graves’ disease
Rationale: Low TSH and high free T4 with hyperthyroid symptoms suggest primary
hyperthyroidism; Graves’ is the most common cause in this age group.
3. A 60-year-old man with COPD develops acute hypoxemia. Chest X-ray shows
hyperinflated lungs without infiltrates. What is the most likely cause?
A) Pulmonary embolism
, B) Pneumothorax
C) Acute bronchitis
D) Asthma exacerbation
B) Pneumothorax
Rationale: COPD patients are at risk for spontaneous pneumothorax, often presenting with
sudden dyspnea and hyperresonance on exam.
4. A 25-year-old woman has dysuria, frequency, and suprapubic pain. Urinalysis shows
positive leukocyte esterase and nitrites. Most appropriate treatment?
A) Ciprofloxacin
B) Nitrofurantoin
C) Amoxicillin
D) TMP-SMX
B) Nitrofurantoin
Rationale: Uncomplicated cystitis in women is commonly treated with nitrofurantoin;
avoid fluoroquinolones first-line due to resistance and side effects.
5. A 70-year-old man presents with difficulty initiating urination, weak stream, and
nocturia. PSA is normal. Most likely diagnosis?
A) Prostate cancer
B) BPH
C) Bladder cancer
D) Neurogenic bladder
B) BPH
Rationale: Symptoms of obstructive and irritative urinary issues in an older male with
normal PSA are classic for benign prostatic hyperplasia.
6. A 55-year-old woman with diabetes presents with right eye pain, redness, and vision
loss. Slit-lamp shows a corneal ulcer. Most likely organism?
A) Staphylococcus aureus
B) Pseudomonas aeruginosa
C) Streptococcus pneumoniae
D) Herpes simplex virus
B) Pseudomonas aeruginosa
Rationale: Contact lens wearers or diabetics are at risk for Pseudomonas keratitis, which
can rapidly cause corneal ulceration.
7. A 40-year-old man presents with fatigue, jaundice, and pruritus. Labs: ALT > AST,
positive ANA, anti-smooth muscle antibodies. Most likely diagnosis?
A) Primary biliary cholangitis
B) Autoimmune hepatitis
, C) Hepatitis C
D) Hemochromatosis
B) Autoimmune hepatitis
Rationale: Positive ANA and anti-smooth muscle antibodies with hepatocellular injury
indicate autoimmune hepatitis.
8. A 5-year-old boy presents with a barking cough and stridor. He is afebrile and in mild
respiratory distress. Most appropriate initial treatment?
A) Antibiotics
B) Racemic epinephrine
C) Corticosteroids
D) Oxygen
C) Corticosteroids
Rationale: Croup is usually viral; corticosteroids reduce airway inflammation. Racemic
epinephrine is for severe cases.
9. A 65-year-old man presents with sudden-onset weakness on the right side and
slurred speech. CT shows an ischemic stroke in the left MCA territory. Which artery
was occluded?
A) Left MCA
B) Right MCA
C) Left ACA
D) Right PCA
A) Left MCA
Rationale: Left MCA strokes cause right-sided weakness and aphasia if in the dominant
hemisphere.
10. A 28-year-old woman presents with fatigue, cold intolerance, weight gain, and dry
skin. Labs: TSH elevated, free T4 low. Most likely diagnosis?
A) Hyperthyroidism
B) Hashimoto’s thyroiditis
C) Subacute thyroiditis
D) Pituitary adenoma
B) Hashimoto’s thyroiditis
Rationale: Primary hypothyroidism with elevated TSH and low free T4 is typical of
Hashimoto’s thyroiditis.
11. A 55-year-old man presents with progressive shortness of breath and dry cough. CT
shows honeycombing at lung bases. Most likely diagnosis?
A) COPD
B) Pulmonary fibrosis
