COMPREHENSIVE OSTEOPATHIC
MEDICAL LICENSING EXAMINATION OF
THE UNITED STATES LEVEL 3 (COMLEX-
USA LEVEL 3) PRACTICE EXAM
QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) PLUS RATIONALES
2026 Q&A | INSTANT DOWNLOAD PDF
1. A 62-year-old man with a history of hypertension presents with sudden
tearing chest pain radiating to the back. Blood pressure differs between
arms. What is the most likely diagnosis?
A. Myocardial infarction
B. Pulmonary embolism
C. Aortic dissection
D. Pericarditis
Answer: C
Rationale: Tearing chest pain radiating to the back with unequal blood pressures
strongly suggests aortic dissection. The condition involves a tear in the intimal
layer of the aorta, creating a false lumen. Immediate diagnosis and management
are critical to prevent rupture or organ ischemia.
2. A 45-year-old woman presents with fatigue and pruritus. Labs show
elevated alkaline phosphatase and antimitochondrial antibodies. Diagnosis?
, A. Primary sclerosing cholangitis
B. Autoimmune hepatitis
C. Primary biliary cholangitis
D. Viral hepatitis
Answer: C
Rationale: Primary biliary cholangitis is characterized by autoimmune destruction
of intrahepatic bile ducts. Elevated ALP and positive antimitochondrial antibodies
are hallmark findings, often presenting with pruritus and fatigue.
3. A patient develops hypotension, wheezing, and urticaria after penicillin
administration. Immediate treatment?
A. Diphenhydramine
B. Epinephrine
C. Prednisone
D. Albuterol
Answer: B
Rationale: Anaphylaxis is a life-threatening condition requiring immediate
intramuscular epinephrine. It reverses airway constriction, vasodilation, and
shock.
4. A 70-year-old man presents with resting tremor, rigidity, and bradykinesia.
Most likely diagnosis?
A. Huntington disease
B. Parkinson disease
C. Essential tremor
D. ALS
Answer: B
Rationale: Parkinson disease is characterized by the triad of resting tremor,
rigidity, and bradykinesia due to dopamine deficiency in the substantia nigra.
, 5. A diabetic patient presents with polyuria, polydipsia, and blood glucose of
600 mg/dL without ketosis. Diagnosis?
A. DKA
B. HHS
C. Hypoglycemia
D. SIADH
Answer: B
Rationale: Hyperosmolar hyperglycemic state (HHS) occurs in type 2 diabetes with
severe hyperglycemia and dehydration but minimal ketosis due to some residual
insulin.
6. A 25-year-old woman presents with lower abdominal pain and cervical
motion tenderness. Diagnosis?
A. Ectopic pregnancy
B. Pelvic inflammatory disease
C. Ovarian torsion
D. Endometriosis
Answer: B
Rationale: Cervical motion tenderness is a classic finding in pelvic inflammatory
disease, usually caused by ascending infection from sexually transmitted
organisms.
7. A patient with chronic alcohol use presents with confusion, ataxia, and
ophthalmoplegia. Treatment?
A. Glucose
B. Thiamine
C. Naloxone
D. Folate
, Answer: B
Rationale: Wernicke encephalopathy is due to thiamine deficiency. Thiamine must
be given before glucose to prevent worsening neurologic injury.
8. A 60-year-old smoker presents with hematuria. Most likely diagnosis?
A. Renal stone
B. Bladder cancer
C. UTI
D. Glomerulonephritis
Answer: B
Rationale: Painless hematuria in a smoker is highly suspicious for bladder cancer,
most commonly transitional cell carcinoma.
9. A patient presents with ST elevations in leads II, III, and aVF. Which artery is
involved?
A. LAD
B. RCA
C. LCX
D. Diagonal
Answer: B
Rationale: Inferior wall myocardial infarction corresponds to ST elevations in II, III,
and aVF, typically due to right coronary artery occlusion.
10.A newborn presents with a continuous machinery murmur. Diagnosis?
A. ASD
B. VSD
C. PDA
D. TOF
MEDICAL LICENSING EXAMINATION OF
THE UNITED STATES LEVEL 3 (COMLEX-
USA LEVEL 3) PRACTICE EXAM
QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) PLUS RATIONALES
2026 Q&A | INSTANT DOWNLOAD PDF
1. A 62-year-old man with a history of hypertension presents with sudden
tearing chest pain radiating to the back. Blood pressure differs between
arms. What is the most likely diagnosis?
A. Myocardial infarction
B. Pulmonary embolism
C. Aortic dissection
D. Pericarditis
Answer: C
Rationale: Tearing chest pain radiating to the back with unequal blood pressures
strongly suggests aortic dissection. The condition involves a tear in the intimal
layer of the aorta, creating a false lumen. Immediate diagnosis and management
are critical to prevent rupture or organ ischemia.
2. A 45-year-old woman presents with fatigue and pruritus. Labs show
elevated alkaline phosphatase and antimitochondrial antibodies. Diagnosis?
, A. Primary sclerosing cholangitis
B. Autoimmune hepatitis
C. Primary biliary cholangitis
D. Viral hepatitis
Answer: C
Rationale: Primary biliary cholangitis is characterized by autoimmune destruction
of intrahepatic bile ducts. Elevated ALP and positive antimitochondrial antibodies
are hallmark findings, often presenting with pruritus and fatigue.
3. A patient develops hypotension, wheezing, and urticaria after penicillin
administration. Immediate treatment?
A. Diphenhydramine
B. Epinephrine
C. Prednisone
D. Albuterol
Answer: B
Rationale: Anaphylaxis is a life-threatening condition requiring immediate
intramuscular epinephrine. It reverses airway constriction, vasodilation, and
shock.
4. A 70-year-old man presents with resting tremor, rigidity, and bradykinesia.
Most likely diagnosis?
A. Huntington disease
B. Parkinson disease
C. Essential tremor
D. ALS
Answer: B
Rationale: Parkinson disease is characterized by the triad of resting tremor,
rigidity, and bradykinesia due to dopamine deficiency in the substantia nigra.
, 5. A diabetic patient presents with polyuria, polydipsia, and blood glucose of
600 mg/dL without ketosis. Diagnosis?
A. DKA
B. HHS
C. Hypoglycemia
D. SIADH
Answer: B
Rationale: Hyperosmolar hyperglycemic state (HHS) occurs in type 2 diabetes with
severe hyperglycemia and dehydration but minimal ketosis due to some residual
insulin.
6. A 25-year-old woman presents with lower abdominal pain and cervical
motion tenderness. Diagnosis?
A. Ectopic pregnancy
B. Pelvic inflammatory disease
C. Ovarian torsion
D. Endometriosis
Answer: B
Rationale: Cervical motion tenderness is a classic finding in pelvic inflammatory
disease, usually caused by ascending infection from sexually transmitted
organisms.
7. A patient with chronic alcohol use presents with confusion, ataxia, and
ophthalmoplegia. Treatment?
A. Glucose
B. Thiamine
C. Naloxone
D. Folate
, Answer: B
Rationale: Wernicke encephalopathy is due to thiamine deficiency. Thiamine must
be given before glucose to prevent worsening neurologic injury.
8. A 60-year-old smoker presents with hematuria. Most likely diagnosis?
A. Renal stone
B. Bladder cancer
C. UTI
D. Glomerulonephritis
Answer: B
Rationale: Painless hematuria in a smoker is highly suspicious for bladder cancer,
most commonly transitional cell carcinoma.
9. A patient presents with ST elevations in leads II, III, and aVF. Which artery is
involved?
A. LAD
B. RCA
C. LCX
D. Diagonal
Answer: B
Rationale: Inferior wall myocardial infarction corresponds to ST elevations in II, III,
and aVF, typically due to right coronary artery occlusion.
10.A newborn presents with a continuous machinery murmur. Diagnosis?
A. ASD
B. VSD
C. PDA
D. TOF
