Topics › System and discipline
Respiratory & Renal Pharmacology — Step 1 practice questions
30 questions in this area, with an explanation for every answer choice.
Three samples below, free and without an account.
How this shows up on Step 1
Pharmacology questions in this section combine two things the exam tests separately elsewhere. Pharmacology is examined as mechanism, effect and adverse effect, rarely as dosing. These two systems are examined together because acid-base links them.
Sample questions
Sample question 1
A 17-year-old boy with severe hypertension since childhood has hypokalemia and metabolic alkalosis. Plasma renin activity and aldosterone are both suppressed. Spironolactone has no effect on his blood pressure. Which of the following drugs is most likely to be effective?
Explanations
A. Amiloride · correct
Liddle syndrome is a gain-of-function mutation in ENaC that prevents its degradation, so the collecting duct reabsorbs sodium (hypertension, volume expansion) and secretes potassium regardless of aldosterone — hence suppressed renin/aldosterone and no response to mineralocorticoid receptor antagonists. Amiloride or triamterene block ENaC directly and are the treatment.
B. Eplerenone
Eplerenone, like spironolactone, blocks the receptor upstream of the constitutively active channel and fails.
C. Furosemide
Loop diuretics also aggravate potassium loss.
D. Hydrochlorothiazide
Thiazides would worsen hypokalemia and do not address the channel defect.
E. Dexamethasone
Dexamethasone treats glucocorticoid-remediable aldosteronism, where aldosterone is high, not suppressed.
Sample question 2
A 62-year-old man with stage 4 chronic kidney disease has a hemoglobin of 9.2 g/dL with normal iron studies. He is started on an erythropoiesis-stimulating agent. Which of the following best describes the appropriate hemoglobin target and the reason for it?
Explanations
A. Target below 7 g/dL to avoid any thrombotic risk
Such a low target forgoes symptomatic benefit and risks transfusion dependence.
B. Target normalization above 13 g/dL to maximize quality of life
Normalization increases cardiovascular events.
C. Target a partial correction around 10–11 g/dL, because normalizing hemoglobin increases stroke, thrombosis, and mortality · correct
Anemia of chronic kidney disease results chiefly from reduced erythropoietin production by peritubular fibroblasts, compounded by uremic marrow suppression and shortened red cell survival. Erythropoiesis-stimulating agents correct it, but trials targeting NORMAL hemoglobin showed increased stroke, vascular access thrombosis, and mortality — so partial correction to roughly 10–11 g/dL is standard, with iron repletion needed to support the response.
D. Iron supplementation should be withheld during therapy
Adequate iron is essential; functional iron deficiency limits the response.
E. Erythropoietin should be avoided entirely in kidney disease
ESAs are a mainstay of management.
Sample question 3
A 7-month-old has 3 days of cough, wheezing, and tachypnea during winter, with nasal flaring and diffuse wheezes and crackles. Oxygen saturation is 94% on room air and he is feeding adequately. Which of the following is the most appropriate management?
Explanations
A. Chest physiotherapy, which shortens hospitalization
Chest physiotherapy has not shown benefit.
B. Scheduled albuterol regardless of response
Routine bronchodilators are not recommended in bronchiolitis.
C. Supportive care with nasal suctioning, hydration, and monitoring, since bronchodilators, corticosteroids, and antibiotics are not routinely beneficial · correct
Bronchiolitis, usually caused by respiratory syncytial virus in infants under 2 during winter, produces inflammation and mucus plugging of small airways with wheezing and crackles. Management is SUPPORTIVE — suctioning, hydration, and oxygen when needed — because trials show no consistent benefit from bronchodilators, corticosteroids, antibiotics, or chest physiotherapy. Palivizumab or nirsevimab provides prophylaxis for high-risk infants, and hospitalization is guided by feeding, work of breathing, and oxygenation rather than wheeze alone.
D. Oral amoxicillin for presumed bacterial pneumonia
Bacterial superinfection is uncommon.
E. Inhaled corticosteroids for 4 weeks
Inhaled steroids do not alter the course or prevent recurrent wheezing.
Practice the rest
Build a quiz from this topic, or sit a full length exam under real conditions.
Start free
