How to use these USMLE Step 2 practice questions
USMLE Step 2 CK is a computer-based, single-day examination made up of multiple timed blocks of single-best-answer questions. The questions use clinical vignettes and mainly test patient-centred reasoning: diagnosis, interpretation of tests, the next best step, management and prevention across core disciplines.
The most useful way to practise is not to count how many facts you recognise. For every question, identify:
- the immediate threat to life or function;
- the problem representation in one sentence;
- the most likely diagnosis and the dangerous alternative;
- whether the next step is stabilisation, a diagnostic test, treatment or triage;
- the finding that makes the best option better than its closest distractor.
The questions below are designed to be answered one at a time. Read the vignette, select the option, then use the explanation to examine your reasoning. A correct answer reached by an unsafe or unfocused process is still worth reviewing.
Question 1 — stabilise before completing the work-up
This tests prioritisation when infection and haemodynamic instability appear together. The safest next step is more important than obtaining every possible result.
A Step 2 practice question on this decision looks like this:
A 67-year-old man with diabetes presents with fever, confusion and a painful left lower leg. Temperature is 39.2°C, blood pressure is 82/48 mm Hg, pulse is 124/min and respirations are 28/min. The leg is erythematous with bullae and crepitus. Lactate is 4.8 mmol/L. Which of the following is the most appropriate next step?
Intravenous broad-spectrum antibiotics, rapid crystalloid resuscitation and urgent surgical consultation are required. The patient has septic shock with possible necrotising soft-tissue infection; imaging must not delay treatment and surgical assessment. MRI may define the extent but is not the next priority. Waiting for cultures or using corticosteroids first leaves a life-threatening infection untreated.
The discriminator is the combination of shock and a rapidly destructive soft-tissue process. The option that delays antibiotics, resuscitation or source control is unsafe.
Question 2 — choose a test from pretest probability
This question tests whether you can use the clinical probability of disease rather than order a broad panel without a decision in mind.
The next question focuses on a patient whose symptoms are concerning but do not indicate immediate instability:
A 58-year-old man has 3 months of pressure-like chest discomfort when walking uphill. It resolves within 5 minutes of rest. He has hypertension and hyperlipidaemia. Resting ECG is normal, and he has no pain at rest. Which of the following is the most appropriate next step in evaluation?
This is stable, exertional chest pain with an intermediate probability of obstructive coronary disease. Noninvasive anatomic or functional testing is appropriate. Coronary angiography is usually reserved for high-risk findings or persistent symptoms despite initial management. D-dimer evaluates venous thromboembolism, not this presentation, and a normal resting ECG does not exclude stable coronary disease.
The strongest distractor is urgent angiography: it sounds definitive, but the patient is stable and has not yet had noninvasive risk assessment.
Question 3 — correct the physiology before insulin
This tests a common diabetic emergency trap: treatment of ketoacidosis depends on the serum potassium concentration.
A 24-year-old woman with type 1 diabetes has vomiting, abdominal pain and confusion. Glucose is 31 mmol/L, arterial pH is 7.12, bicarbonate is 9 mmol/L and serum potassium is 2.8 mmol/L. Which of the following should be done first?
Potassium must be replaced before insulin when serum potassium is below 3.3 mmol/L. Insulin drives potassium into cells and can precipitate a fatal arrhythmia in severe hypokalaemia. Intravenous fluids are also required, but starting insulin before correcting this potassium level is unsafe. Bicarbonate is not routinely given at this pH unless severe acidemia has specific indications.
A glucose value can draw attention away from the more urgent electrolyte danger. In a timed block, check potassium before selecting insulin for diabetic ketoacidosis.
Question 4 — treat uterine atony promptly
This tests recognition of the common immediate cause of postpartum haemorrhage and the first action that addresses it.
A 29-year-old woman has heavy vaginal bleeding 20 minutes after an uncomplicated vaginal delivery. The placenta is complete. Her uterus is enlarged and boggy on examination. Blood pressure is 96/60 mm Hg and pulse is 118/min. Which of the following is the most appropriate initial management?
A boggy, enlarged uterus after delivery indicates uterine atony. Uterine massage and oxytocin are first-line measures, alongside resuscitation and assessment of ongoing blood loss. A complete placenta makes retained tissue less likely, and observation is inappropriate in active haemorrhage. Additional uterotonics, procedures or surgery depend on response and the cause.
The key sequence is resuscitation, uterine massage, oxytocin and simultaneous assessment for retained tissue, laceration or coagulopathy.
Question 5 — protect the airway in epiglottitis
This question tests whether a frightening airway presentation is managed before an examination that could worsen obstruction.
A 4-year-old child has sudden fever, drooling, muffled speech and prefers to sit leaning forward. The child is anxious and has inspiratory stridor. Which of the following is the most appropriate next step?
The presentation suggests epiglottitis with impending upper-airway obstruction. Keep the child calm, avoid upsetting airway examination and secure the airway in a controlled setting with anaesthesia and otolaryngology support. Oropharyngeal examination or forcing the child supine can precipitate complete obstruction. Radiography should not delay airway management.
The best answer is defined by safety, not convenience. Do not choose the test that confirms the diagnosis if the child may obstruct while waiting for it.
Question 6 — image before reperfusion treatment
This tests the immediate pathway for a patient with a focal neurological deficit and a recent onset.
A 71-year-old woman develops sudden right-sided weakness and aphasia while eating breakfast. She arrives 90 minutes after symptom onset. Glucose is normal, and she takes no anticoagulants. Which of the following is the most appropriate next step?
Urgent noncontrast CT of the head is needed to exclude intracranial haemorrhage before considering intravenous thrombolysis. The recent onset and disabling deficit make this time-critical. Aspirin or heparin should not be given before haemorrhage is excluded, and lumbar puncture has no role in this initial pathway.
The sequence is important: establish the last-known-well time, check glucose, obtain urgent brain imaging and then assess eligibility for reperfusion treatment.
Question 7 — use the right imaging for obstructive jaundice
This tests investigation of a high-risk pattern rather than starting with an unrelated laboratory panel.
A 69-year-old man has progressive painless jaundice, weight loss and pale stools. Examination shows a palpable, nontender gallbladder. Alkaline phosphatase and bilirubin are markedly elevated. Which of the following is the most appropriate next diagnostic step?
Progressive painless obstructive jaundice with weight loss raises concern for a pancreatic head or biliary malignancy. Pancreas-protocol contrast CT assesses the lesion, vascular involvement and resectability. Amylase is not an adequate cancer evaluation, and cholecystectomy or hepatitis treatment does not address the obstructive pattern.
A palpable gallbladder with painless jaundice is a useful discriminator for malignant obstruction, although imaging is needed to establish the cause and extent.
Question 8 — treat severe symptoms, not just a number
This question tests management of hyponatraemia in a patient with a likely ectopic antidiuretic hormone source.
A 63-year-old man with newly diagnosed small-cell lung carcinoma becomes confused and has a generalised seizure. Serum sodium is 114 mmol/L, serum osmolality is low and urine is inappropriately concentrated. Which of the following is the most appropriate immediate treatment?
Seizure and severe symptomatic hyponatraemia require carefully monitored hypertonic saline to raise serum sodium enough to control cerebral symptoms. Correction must be controlled to reduce the risk of osmotic demyelination. Fluid restriction may be used later for SIADH in suitable patients but is too slow for this emergency.
The important distinction is severe symptoms versus an incidental laboratory abnormality. Avoid both undertreatment and excessive correction.
Question 9 — manage a common medication adverse effect
This tests whether you can identify an adverse drug effect and choose a medication with a similar benefit but a different mechanism of the unwanted effect.
A 52-year-old woman started lisinopril 6 weeks ago for hypertension. Her blood pressure has improved, but she now has a persistent dry cough. Chest examination and radiograph are normal. Which of the following is the most appropriate change?
A persistent dry cough is a recognised adverse effect of ACE inhibition, related to bradykinin. Switching to an angiotensin receptor blocker preserves renin-angiotensin system treatment while usually avoiding the cough. Increasing the ACE-inhibitor dose worsens the likely cause, and antibiotics are not indicated without evidence of infection.
In questions about medication side effects, check timing, expected adverse effects and whether the replacement preserves the treatment goal.
Question 10 — respect a capacitated refusal
This tests autonomy, capacity and emergency decision-making rather than the clinician’s personal view of the treatment.
A 34-year-old adult with severe gastrointestinal bleeding is alert, understands the proposed blood transfusion, explains the risks of refusing it and consistently declines transfusion for religious reasons. Which of the following is the most appropriate next step?
An adult with decision-making capacity may refuse recommended treatment, even when the refusal risks death. The clinician should document capacity and informed refusal, involve the relevant team and discuss alternatives such as blood-conservation measures that the patient accepts. Family members cannot replace a capacitated patient’s decision, and coercive treatment is not justified by the seriousness of the risk alone.
This is a patient-safety and ethics question. Do not confuse disagreement with incapacity; assess understanding, appreciation, reasoning and communication of a choice.
Review the pattern, not only the score
After the ten questions, classify each error:
- Recognition error: you did not identify the syndrome or key finding.
- Priority error: you recognised the diagnosis but ignored instability or airway risk.
- Test-selection error: you chose a test without considering pretest probability or timing.
- Management error: you knew the diagnosis but selected a later-line treatment.
- Safety or ethics error: you missed a contraindication, consent issue or harmful delay.
A review screen for this set might rank your misses as follows:
Do not reread every explanation equally. Start with the lowest section, then return to the individual decision that caused the error. Your next revision item should be small enough to test again: for example, “In diabetic ketoacidosis, hold insulin when potassium is below 3.3 mmol/L and replace potassium first.”
A remediation tray can turn a repeated error into one targeted prompt:
You lost this mark twice: in diabetic ketoacidosis, what serum potassium threshold requires potassium replacement before starting insulin?
Repeat the question later in a new vignette. The goal is not to memorise the wording above; it is to make the same prioritisation reliably under timed conditions.
How MySummaries helps
MySummaries can turn your own Step 2 CK notes into a revision board, then generate single-best-answer practice, spaced-repetition cards and targeted remediation from repeated errors. It can also create written mock papers and audio reviews from the same material. Open MySummaries to build a board for the clinical areas you are currently missing.