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DHA GP Exam study materials
DHA GP Exam study resources

DHA GP Exam practice questions

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Question 1Internal Medicine

A 58-year-old Black man has stage 1 hypertension and no diabetes or chronic kidney disease. Which medication is preferred as initial monotherapy?

  1. Amlodipine Correct answer.
  2. Spironolactone
  3. Metoprolol
  4. Lisinopril

Explanation

In Black adults without diabetes or chronic kidney disease, a thiazide diuretic or a calcium-channel blocker is preferred as initial antihypertensive therapy because ACE inhibitor monotherapy is less effective in this group. Amlodipine is a dihydropyridine calcium-channel blocker.

Question 2Internal Medicine

Which fasting plasma glucose value meets the diagnostic threshold for diabetes mellitus?

  1. 126 mg/dL Correct answer.
  2. 100 mg/dL
  3. 120 mg/dL
  4. 110 mg/dL

Explanation

A fasting plasma glucose of 126 mg/dL or higher meets the diagnostic threshold for diabetes when confirmed or accompanied by typical symptoms. Values from 100 to 125 mg/dL indicate prediabetes.

Question 3Internal Medicine

What is the preferred daily controller medication for a patient with persistent asthma?

  1. Oral prednisone daily
  2. Low-dose inhaled corticosteroid Correct answer.
  3. Albuterol as needed
  4. Montelukast monotherapy

Explanation

Inhaled corticosteroids are the most effective long-term controller therapy for persistent asthma and reduce exacerbations. Short-acting beta agonists are used for symptom relief, not daily control.

Question 4Internal Medicine

Which agent is most effective for healing erosive esophagitis in GERD?

  1. Ranitidine
  2. Calcium carbonate
  3. Omeprazole Correct answer.
  4. Sucralfate

Explanation

Proton pump inhibitors such as omeprazole produce the greatest acid suppression and are most effective for healing erosive esophagitis. Antacids and H2 blockers provide symptomatic relief but are less effective for mucosal healing.

Question 5Internal Medicine

A 34-year-old woman has microcytic anemia, low ferritin, and normal hemoglobin electrophoresis. What is the most likely cause?

  1. Iron deficiency anemia Correct answer.
  2. Anemia of chronic disease
  3. Thalassemia trait
  4. Sideroblastic anemia

Explanation

Low ferritin is the most specific marker of iron deficiency, and iron deficiency causes microcytic anemia. Thalassemia trait usually has normal or elevated ferritin.

Question 6Internal Medicine

Which antibiotic is first-line for uncomplicated cystitis in a nonpregnant woman with normal renal function?

  1. Ciprofloxacin
  2. Nitrofurantoin Correct answer.
  3. Azithromycin
  4. Amoxicillin

Explanation

Nitrofurantoin is first-line for uncomplicated cystitis because it concentrates in urine and has good activity against common uropathogens. Fluoroquinolones are reserved for more complicated infections.

Question 7Internal Medicine

Which finding is most characteristic of diabetic ketoacidosis?

  1. Anion gap metabolic acidosis Correct answer.
  2. pH 7.45
  3. Bicarbonate 30 mEq/L
  4. Negative serum ketones

Explanation

Diabetic ketoacidosis is characterized by hyperglycemia, ketonemia, and a high anion gap metabolic acidosis. Bicarbonate is typically low, and ketones are positive.

Question 8Internal Medicine

Which artery is most commonly affected in a lacunar stroke?

  1. Basilar artery
  2. Posterior cerebral artery
  3. Vertebral artery
  4. Lenticulostriate artery Correct answer.

Explanation

Lacunar infarcts result from occlusion of small penetrating arteries, most often the lenticulostriate branches of the middle cerebral artery. They typically cause pure motor or sensory deficits.

Question 9Internal Medicine

A 62-year-old man has crushing chest pain with ST elevation in leads II, III, and aVF. Which coronary artery is most likely occluded?

  1. Left circumflex artery
  2. Right coronary artery Correct answer.
  3. Left anterior descending artery
  4. Left main coronary artery

Explanation

ST elevation in leads II, III, and aVF indicates an inferior wall myocardial infarction, usually due to right coronary artery occlusion. The left anterior descending artery affects anterior leads.

Question 10Internal Medicine

Which medication improves survival in heart failure with reduced ejection fraction?

  1. Amlodipine
  2. Digoxin
  3. Furosemide
  4. Sacubitril-valsartan Correct answer.

Explanation

Sacubitril-valsartan is an angiotensin receptor-neprilysin inhibitor that reduces mortality and hospitalization in heart failure with reduced ejection fraction. Loop diuretics improve symptoms but not survival.

Question 11Internal Medicine

A 70-year-old with nonvalvular atrial fibrillation has a CHA2DS2-VASc score of 3. What is indicated for stroke prevention?

  1. Oral anticoagulation Correct answer.
  2. No anticoagulation
  3. Clopidogrel alone
  4. Aspirin alone

Explanation

A CHA2DS2-VASc score of 2 or higher in men, or 3 or higher in women, generally warrants oral anticoagulation. Antiplatelet therapy is inferior to anticoagulation for atrial fibrillation-related stroke prevention.

Question 12Internal Medicine

A patient with chronic dyspnea and a smoking history has a post-bronchodilator FEV1/FVC ratio of 0.60. What is the diagnosis?

  1. Restrictive lung disease
  2. Normal spirometry
  3. COPD Correct answer.
  4. Asthma

Explanation

A post-bronchodilator FEV1/FVC ratio below 0.70 confirms persistent airflow obstruction, consistent with COPD in a patient with risk factors. Asthma can also cause obstruction but is typically reversible.

Question 13Internal Medicine

A 65-year-old with community-acquired pneumonia has a CURB-65 score of 2. What is the appropriate disposition?

  1. Admit to ICU
  2. Withhold antibiotics
  3. Admit to hospital Correct answer.
  4. Discharge home

Explanation

A CURB-65 score of 2 indicates moderate risk and generally warrants hospital admission. Scores of 0 to 1 may be managed as outpatients, while 3 or more suggest severe pneumonia.

Question 14Internal Medicine

What is first-line pharmacologic therapy for ascites due to cirrhosis?

  1. Large-volume paracentesis
  2. Intravenous albumin
  3. Transjugular intrahepatic portosystemic shunt
  4. Spironolactone plus furosemide Correct answer.

Explanation

A combination of spironolactone and furosemide is first-line for cirrhotic ascites, with spironolactone as the mainstay. Albumin and transjugular intrahepatic portosystemic shunt are reserved for specific complications or refractory ascites.

Question 15Internal Medicine

Which finding defines severe acute pancreatitis by the revised Atlanta classification?

  1. Vomiting
  2. Persistent organ failure for more than 48 hours Correct answer.
  3. Epigastric pain
  4. Lipase three times the upper limit

Explanation

Severe acute pancreatitis is defined by persistent organ failure lasting more than 48 hours. Lipase elevation and pain establish the diagnosis but do not define severity.

Question 16Internal Medicine

A patient develops rising creatinine after NSAID use, with low urine sodium and fractional excretion of sodium below 1%. What type of acute kidney injury is most likely?

  1. Postrenal obstruction
  2. Contrast nephropathy
  3. Acute tubular necrosis
  4. Prerenal acute kidney injury Correct answer.

Explanation

Prerenal acute kidney injury causes avid sodium retention, producing low urine sodium and a fractional excretion of sodium below 1%. NSAIDs reduce renal perfusion and can precipitate prerenal injury.

Question 17Internal Medicine

Which ECG finding is characteristic of hyperkalemia?

  1. Prolonged QT interval
  2. U waves
  3. ST-segment elevation
  4. Peaked T waves Correct answer.

Explanation

Hyperkalemia initially produces tall, peaked T waves and can progress to QRS widening and sine-wave patterns. U waves are associated with hypokalemia.

Question 18Internal Medicine

A patient has weight loss, tremor, heat intolerance, suppressed TSH, and elevated free T4. What is the diagnosis?

  1. Primary hypothyroidism
  2. Subclinical hypothyroidism
  3. Primary hyperthyroidism Correct answer.
  4. Central hypothyroidism

Explanation

Suppressed TSH with elevated free T4 confirms primary hyperthyroidism. Graves disease is a common cause, but the biochemical diagnosis is hyperthyroidism.

Question 19Internal Medicine

What is appropriate treatment for an acute gout attack in a patient with normal renal function?

  1. Naproxen or colchicine Correct answer.
  2. Start allopurinol during the acute attack
  3. Probenecid
  4. High-dose aspirin

Explanation

Acute gout is treated with an NSAID such as naproxen, colchicine, or glucocorticoids to reduce inflammation. Urate-lowering therapy is not initiated during an acute attack unless already established.

Question 20Internal Medicine

Which antibody is most specific for rheumatoid arthritis?

  1. Rheumatoid factor
  2. Anti-histone antibody
  3. Anti-cyclic citrullinated peptide antibody Correct answer.
  4. Antinuclear antibody

Explanation

Anti-cyclic citrullinated peptide antibody has high specificity for rheumatoid arthritis. Rheumatoid factor is sensitive but less specific.

Question 21Internal Medicine

A patient with prolonged vomiting has pH 7.50, PaCO2 48 mmHg, and HCO3 36 mEq/L. Which acid-base disorder is present?

  1. Metabolic acidosis
  2. Respiratory alkalosis
  3. Respiratory acidosis
  4. Metabolic alkalosis with respiratory compensation Correct answer.

Explanation

The elevated pH and bicarbonate indicate metabolic alkalosis, and the PaCO2 is increased as respiratory compensation. Vomiting causes loss of gastric acid and chloride-responsive metabolic alkalosis.

Question 22Internal Medicine

A euvolemic patient has hyponatremia, urine osmolality above 100 mOsm/kg, urine sodium above 40 mEq/L, and normal thyroid and adrenal function. What is the most likely diagnosis?

  1. Diuretic-induced hyponatremia
  2. Primary polydipsia
  3. Syndrome of inappropriate antidiuretic hormone Correct answer.
  4. Diabetes insipidus

Explanation

Syndrome of inappropriate antidiuretic hormone causes euvolemic hyponatremia with concentrated urine and high urine sodium in the absence of thyroid or adrenal dysfunction. Primary polydipsia typically produces dilute urine.

Question 23Internal Medicine

A patient with known Addison disease presents with hypotension, hyponatremia, and hyperkalemia. What is the immediate treatment?

  1. Fludrocortisone alone
  2. Insulin and glucose
  3. Oral prednisone
  4. Intravenous hydrocortisone and saline Correct answer.

Explanation

Adrenal crisis requires prompt intravenous hydrocortisone and volume resuscitation with saline. Glucose may be given if hypoglycemia is present, but insulin would worsen it.

Question 24Internal Medicine

A patient develops a platelet count drop from 250,000 to 80,000/µL on day 6 of unfractionated heparin, with new thrombosis. What is the best management?

  1. Continue heparin
  2. Stop heparin and start argatroban Correct answer.
  3. Warfarin alone
  4. Platelet transfusion

Explanation

This is heparin-induced thrombocytopenia with thrombosis. Heparin must be stopped immediately, and a non-heparin anticoagulant such as argatroban is started.

Question 25Internal Medicine

A patient with episodic headache, sweating, palpitations, hypertension, and elevated plasma metanephrines is being prepared for surgery. Which medication should be started first?

  1. Phenoxybenzamine Correct answer.
  2. Furosemide
  3. Propranolol
  4. Amlodipine

Explanation

Preoperative preparation for pheochromocytoma requires alpha-adrenergic blockade first, typically with phenoxybenzamine, to prevent hypertensive crisis. Beta-blockade is added only after alpha-blockade.

Question 26Internal Medicine

A 72-year-old man has exertional dyspnea and syncope. Examination reveals a harsh crescendo-decrescendo systolic murmur at the right second intercostal space that radiates to the carotids. What is the most likely diagnosis?

  1. Aortic stenosis Correct answer.
  2. Ventricular septal defect
  3. Hypertrophic cardiomyopathy
  4. Mitral regurgitation

Explanation

Aortic stenosis produces a crescendo-decrescendo systolic murmur at the right upper sternal border that radiates to the carotids, and it classically causes angina, syncope, or dyspnea. The other murmurs have different locations and radiation patterns.

Question 27Internal Medicine

A 45-year-old woman has fatigue and pica. Laboratory tests show microcytic anemia with a low serum ferritin. What is the most likely diagnosis?

  1. Sideroblastic anemia
  2. Iron deficiency anemia Correct answer.
  3. Thalassemia trait
  4. Anemia of chronic disease

Explanation

A low serum ferritin is the most specific laboratory marker of iron deficiency, and pica is a classic associated symptom. Microcytosis with low ferritin supports iron deficiency anemia rather than the other microcytic disorders.

Question 28Internal Medicine

A patient with cirrhosis develops confusion, asterixis, and an elevated ammonia level. Which medication is first-line to reduce intestinal ammonia absorption?

  1. Lactulose Correct answer.
  2. Omeprazole
  3. Rifaximin
  4. Spironolactone

Explanation

Lactulose is first-line therapy for hepatic encephalopathy because it acidifies the colon and traps ammonia in the stool. Rifaximin is typically added for recurrent or persistent episodes rather than used alone initially.

Question 29Internal Medicine

A 50-year-old average-risk adult has no gastrointestinal symptoms. Which colorectal cancer screening strategy is appropriate?

  1. CT colonography every 10 years from age 50
  2. Stool DNA testing every 10 years from age 50
  3. Flexible sigmoidoscopy every 10 years from age 50
  4. Colonoscopy every 10 years from age 50 Correct answer.

Explanation

Average-risk adults should begin colorectal cancer screening around age 45 to 50, and colonoscopy every 10 years is an accepted strategy. The other listed tests are valid options only at shorter intervals.

Question 30Internal Medicine

A 28-year-old presents with an acute asthma exacerbation, wheezing, respiratory rate 30/min, and oxygen saturation 90% on room air. What is the most appropriate initial treatment?

  1. Inhaled corticosteroid alone
  2. Intravenous antibiotics
  3. Inhaled short-acting beta-agonist Correct answer.
  4. Oral montelukast

Explanation

Acute asthma is treated first with inhaled short-acting beta-agonists, supplemental oxygen, and systemic corticosteroids. Montelukast and inhaled corticosteroids alone are not rescue therapies for an acute exacerbation.

Question 31Internal Medicine

A patient has continuous generalized tonic-clonic seizure activity lasting 5 minutes. What is the first-line medication?

  1. Intravenous lorazepam Correct answer.
  2. Oral phenytoin
  3. Intravenous mannitol
  4. Intramuscular haloperidol

Explanation

Status epilepticus is treated first with a benzodiazepine such as intravenous lorazepam to terminate seizure activity. Phenytoin is a second-line agent used after benzodiazepines.

Question 32Internal Medicine

A 25-year-old presents with periorbital edema, proteinuria of 8 g/day, normal renal function, and no hematuria. What is the most likely diagnosis?

  1. IgA nephropathy
  2. Membranous nephropathy
  3. Minimal change disease Correct answer.
  4. Focal segmental glomerulosclerosis

Explanation

Minimal change disease is a common cause of nephrotic syndrome in young adults and children, with selective proteinuria and normal light microscopy. Membranous nephropathy is more typical in older adults, and IgA nephropathy usually presents with hematuria.

Question 33Internal Medicine

A hospitalized patient develops watery diarrhea after a course of antibiotics, and stool testing confirms Clostridioides difficile infection. What is the first-line treatment for an initial nonsevere episode?

  1. Oral ciprofloxacin
  2. Intravenous metronidazole
  3. Intravenous vancomycin
  4. Oral vancomycin Correct answer.

Explanation

Oral vancomycin or fidaxomicin is first-line for initial C. difficile infection because the drug must reach the colonic lumen. Intravenous vancomycin does not achieve adequate intraluminal concentrations.

Question 34Internal Medicine

A 60-year-old with type 2 diabetes and chronic kidney disease has blood pressure 150/90 mmHg and a urine albumin-to-creatinine ratio of 300 mg/g. Which antihypertensive is preferred?

  1. Beta blocker
  2. Amlodipine
  3. ACE inhibitor Correct answer.
  4. Hydrochlorothiazide

Explanation

An ACE inhibitor or ARB is preferred in albuminuric chronic kidney disease because it reduces albuminuria and slows progression. Blood pressure and renal function should be monitored after initiation.

Question 35Internal Medicine

A 35-year-old has sharp pleuritic chest pain that worsens when lying flat. ECG shows diffuse ST elevation and PR depression. What is the diagnosis?

  1. Pulmonary embolism
  2. Early repolarization
  3. Acute pericarditis Correct answer.
  4. ST-elevation myocardial infarction

Explanation

Diffuse concave ST elevation with PR depression and positional pleuritic pain is characteristic of acute pericarditis. Myocardial infarction usually produces regional ST elevation.

Question 36Internal Medicine

A 65-year-old postmenopausal woman has a femoral neck T-score of -2.8. What is the most appropriate first-line pharmacologic therapy?

  1. Alendronate Correct answer.
  2. Raloxifene
  3. Teriparatide
  4. Calcium and vitamin D alone

Explanation

A bisphosphonate such as alendronate is first-line pharmacologic therapy for postmenopausal osteoporosis. Calcium and vitamin D are adjuncts, while teriparatide is reserved for severe or high-risk disease.

Question 37Internal Medicine

A patient with newly diagnosed rheumatoid arthritis has persistent synovitis. What is the preferred first-line disease-modifying antirheumatic drug?

  1. Sulfasalazine
  2. Methotrexate Correct answer.
  3. Etanercept
  4. Hydroxychloroquine

Explanation

Methotrexate is the anchor DMARD for rheumatoid arthritis and is started early to prevent joint damage. Biologic agents such as etanercept are added when methotrexate is inadequate.

Question 38Internal Medicine

A patient has a pleural effusion. Pleural fluid protein is 3.5 g/dL with serum protein 6.0 g/dL, and pleural LDH is 250 U/L with serum LDH 200 U/L. How should the effusion be classified?

  1. Transudate
  2. Chylothorax
  3. Exudate Correct answer.
  4. Empyema

Explanation

The effusion is an exudate because the pleural-to-serum protein ratio is 0.58 and the LDH ratio is 1.25, both above Light criteria thresholds. Exudates require further evaluation for infection, malignancy, or inflammation.

Question 39Internal Medicine

A patient with acute leukemia has an absolute neutrophil count of 400/µL and a fever of 38.5°C. What is the most appropriate empiric therapy?

  1. Oral amoxicillin
  2. Intravenous acyclovir
  3. An antipseudomonal beta-lactam Correct answer.
  4. Oral fluconazole

Explanation

Febrile neutropenia requires immediate broad-spectrum coverage with an antipseudomonal beta-lactam, such as piperacillin-tazobactam or cefepime. Antifungal or antiviral agents are added based on specific risk factors and cultures.

Question 40Internal Medicine

A patient with Burkitt lymphoma develops potassium 6.5 mEq/L, phosphate 7 mg/dL, calcium 7.5 mg/dL, uric acid 12 mg/dL, and rising creatinine after chemotherapy. What is the best initial management?

  1. Intravenous furosemide alone
  2. Intravenous hydration and rasburicase Correct answer.
  3. Oral allopurinol alone
  4. Intravenous calcium gluconate

Explanation

This is tumor lysis syndrome; aggressive intravenous hydration and rasburicase are central to lowering uric acid and preventing renal injury. Calcium is given only for symptomatic hypocalcemia, and allopurinol is used for prophylaxis rather than acute hyperuricemia.

Question 41Family Medicine and Primary Care

A 56-year-old Black man is newly diagnosed with hypertension. He has no diabetes, no albuminuria and no other comorbidity. Which class is the most appropriate initial antihypertensive therapy?

  1. Thiazide-type diuretic Correct answer.
  2. Beta-blocker
  3. Alpha-1 blocker
  4. Loop diuretic

Explanation

In Black adults without diabetes or chronic kidney disease, a thiazide-type diuretic or a calcium channel blocker is preferred first-line because renin-angiotensin blockade is less effective in this group. Beta-blockers and alpha-blockers are not recommended as initial monotherapy for uncomplicated hypertension.

Question 42Family Medicine and Primary Care

Which laboratory result establishes a diagnosis of diabetes mellitus in an asymptomatic adult?

  1. HbA1c 6.7% Correct answer.
  2. Fasting plasma glucose 6.1 mmol/L
  3. Random plasma glucose 9.4 mmol/L
  4. 2-hour OGTT glucose 9.6 mmol/L

Explanation

An HbA1c of 6.5% or more meets the diagnostic threshold for diabetes, provided the assay is standardised and no condition such as haemoglobinopathy distorts the result. The other values fall in the prediabetic or non-diagnostic range.

Question 43Family Medicine and Primary Care

Which inhaled agent is the preferred reliever for acute asthma symptoms?

  1. Leukotriene receptor antagonist
  2. Short-acting beta-2 agonist Correct answer.
  3. Long-acting beta-2 agonist
  4. Inhaled corticosteroid

Explanation

A short-acting beta-2 agonist provides rapid bronchodilation and is the standard as-needed reliever in asthma. Controller agents act on airway inflammation and do not relieve acute symptoms.

Question 44Family Medicine and Primary Care

A 3-year-old child has acute otitis media with no penicillin allergy and no recent antibiotic use. Which is the recommended first-line antibiotic?

  1. Amoxicillin-clavulanate
  2. Azithromycin
  3. High-dose amoxicillin Correct answer.
  4. Cefuroxime

Explanation

High-dose amoxicillin gives good coverage of Streptococcus pneumoniae, including most penicillin-non-susceptible strains, and is the recommended initial agent for uncomplicated acute otitis media. Amoxicillin-clavulanate is reserved for treatment failure, recent antibiotic exposure or concurrent purulent conjunctivitis.

Question 45Family Medicine and Primary Care

What daily dose of folic acid is recommended before conception for a woman at average risk of a neural tube defect?

  1. 400 micrograms daily Correct answer.
  2. 1 milligram daily
  3. 5 milligrams weekly
  4. 4 milligrams daily

Explanation

Average-risk women should take 400 micrograms of folic acid daily starting at least one month before conception and continuing through the first trimester. Higher doses are reserved for women with additional risk factors such as previous affected pregnancy or diabetes.

Question 46Family Medicine and Primary Care

At what age is the first routine dose of the measles-mumps-rubella vaccine given?

  1. 4 years
  2. 12 months Correct answer.
  3. 6 years
  4. 6 months

Explanation

The first MMR dose is scheduled at 12 to 15 months of age, when maternal antibody interference has waned and an adequate immune response develops. A second dose is given later, typically at 4 to 6 years.

Question 47Family Medicine and Primary Care

Which laboratory test is most useful to confirm iron deficiency in an anaemic adult?

  1. Reticulocyte count
  2. Serum vitamin B12
  3. Peripheral blood film
  4. Serum ferritin Correct answer.

Explanation

A low serum ferritin is the most specific single indicator of depleted iron stores in an anaemic patient. Because ferritin is an acute-phase reactant, a normal value does not fully exclude deficiency when inflammation is present.

Question 48Family Medicine and Primary Care

A patient has a raised thyroid-stimulating hormone with a low free T4. Which diagnosis fits this pattern?

  1. Primary hypothyroidism Correct answer.
  2. Subclinical hypothyroidism
  3. Secondary hypothyroidism
  4. Euthyroid sick syndrome

Explanation

A high TSH with a low free T4 indicates failure of the thyroid gland with intact pituitary feedback, which defines primary hypothyroidism. Subclinical disease has a normal free T4, and central hypothyroidism shows a low or inappropriately normal TSH.

Question 49Family Medicine and Primary Care

A non-pregnant woman has uncomplicated acute cystitis with dysuria and frequency, and no drug allergies. Which is the most appropriate empiric therapy?

  1. Amoxicillin 3 days
  2. Nitrofurantoin 5 days Correct answer.
  3. Ciprofloxacin 7 days
  4. Doxycycline 10 days

Explanation

Nitrofurantoin for five days is a first-line option for uncomplicated cystitis because it achieves high urinary concentrations and resistance rates remain low. Fluoroquinolones are reserved for more complicated infections to limit collateral resistance.

Question 50Family Medicine and Primary Care

A 7-year-old has a temperature of 38.5°C, tonsillar exudates, tender anterior cervical nodes and no cough. What is the most appropriate next step?

  1. Prescribe amoxicillin immediately
  2. Throat culture, await result
  3. Rapid antigen detection test Correct answer.
  4. Reassure and give supportive care

Explanation

The modified Centor criteria score in this child is high, so microbiological confirmation is needed before antibiotics because most pharyngitis is viral. A rapid antigen test allows same-visit decisions, with culture reserved for negative results in children when suspicion remains.