Pharmacology K16 P2 – Answers and Explanations

Pharmacology K16 P2 – Answers and Explanations

Question 60:

• Question: Which antibiotic causes gray syndrome in children?

• Answer: D. Chloramphenicol

• Explanation: Chloramphenicol is an antibiotic that can be toxic to children, especially causing gray syndrome, a serious condition affecting the central nervous system.

Question 61:

• Question: What is the route of administration of Vancomycin in the treatment of systemic infections?

• Answer: A. IV

• Explanation: Vancomycin is usually administered intravenously (IV) in the treatment of systemic infections due to its poor absorption through the gastrointestinal tract.

Question 62:

• Question: Which H1 antihistamine is used to treat motion sickness?

• Answer: A. Promethazine

• Explanation: Promethazine is an H1 antihistamine with antiemetic and antivertigo effects, often used to treat motion sickness.

Question 63:

• Question: Which of the following is a WRONG contraindication of morphine?

• Answer: D. Appendicitis

• Explanation: Morphine is not contraindicated in appendicitis. Contraindications of morphine include respiratory depression, alcohol intoxication, barbiturates, and children under 30 months of age.

Question 64:

• Question: What is the effect of cetirizine on histamine receptors?

• Answer: A. Reversible antagonism

• Explanation: Cetirizine is an H1 antihistamine that exerts reversible antagonism on histamine receptors.

Question 65:

• Question: Which of the following statements is true regarding the lipid metabolism effect of corticosteroids?

• Answer: D. All of the above

• Explanation: Corticosteroids have lipid metabolism effects including:

• Lipid depletion in fat cells

• Increased glycerol and free fatty acids

• Redistribution of lipids in the upper half of the body

Question 67:

• Question: Choose the CORRECT statement?

• Answer: C. Only the free drug form can move between compartments in the body

• Explanation: Only the free drug form can cross cell membranes and distribute into tissues in the body. The drug form bound to plasma proteins cannot cross cell membranes.

Question 68:

• Question: Which of the following laxatives is also used to support the treatment of hepatic encephalopathy?

• Answer: C. Lactulose

• Explanation: Lactulose is a laxative used in the treatment of hepatic encephalopathy as it reduces blood ammonia levels.

Question 69:

• Question: SMECTA is the trade name of a drug used in which of the following conditions?

• Answer: B. Diarrhea

• Explanation: SMECTA is an anti-diarrheal drug, commonly used to treat acute diarrhea.

Question 71:

• Question: Which of the following anti-inflammatory mechanisms of NSAIDs is incorrect?

• Answer: A. Inhibition of lysosomal membrane stabilization

• Explanation: NSAIDs do not inhibit lysosomal membrane stabilization. The primary mechanism of NSAIDs is the inhibition of COX-1 and COX-2 enzymes, leading to reduced prostaglandin production.

Question 72:

• Question: Which NSAID is indicated for both acute and long-term arthritis?

• Answer: A. Tenoxicam

• Explanation: Tenoxicam is an NSAID with long-lasting effects, often indicated for both acute and long-term arthritis.

Question 73:

• Question: Which of the following antibiotics has a prolonged post-antibiotic effect (PAE) that is clinically significant?

• Answer: C. Aminoglycosides

• Explanation: Aminoglycosides have a prolonged post-antibiotic effect (PAE), meaning the drug continues to have bactericidal effects even after serum drug concentrations fall below the minimum inhibitory concentration.

Question 74:

• Question: According to the US Food and Drug Administration (FDA) on the safety of drugs for pregnant women, how many categories are drugs classified into?

• Answer: C. 5

• Explanation: The FDA classifies drugs according to their safety for pregnant women into 5 categories: A, B, C, D, and X.

Question 75:

• Question: What is the general principle in using NSAIDs except?

• Answer: A. Taking multiple NSAIDs together

• Explanation: Multiple NSAIDs should not be taken together as this can increase the risk of side effects, especially gastrointestinal side effects.

Question 76:

• Question: Which of the following drugs reduces phase 0 of the action potential, reducing AV conduction to a moderate extent and prolonging repolarization?

• Answer: A. Procainamide

• Explanation: Procainamide is an antiarrhythmic drug that depresses phase 0 of the action potential, reduces AV conduction to a moderate extent, and prolongs repolarization.

Question 77:

• Question: A patient with a long history of cardiovascular disease is found to have increasingly severe ventricular arrhythmias. Which of the following drugs has the highest risk of causing arrhythmias?

• Answer: C. Dobutamine

• Explanation: Dobutamine is an inotropic drug that can cause ventricular arrhythmias, especially in patients with a history of cardiovascular disease.

Question 78:

• Question: A patient is admitted to the emergency room for ventricular tachycardia after an acute myocardial infarction. This type of arrhythmia is life-threatening and must be controlled immediately. Which of the following drugs is the best choice in this situation?

• Answer: D. Lidocaine

• Explanation: Lidocaine is an effective antiarrhythmic drug in treating ventricular tachycardia after acute myocardial infarction.

Question 79:

• Question: A female patient with a history of bronchospasm complains that she often experiences shortness of breath accompanied by nausea whenever she plays volleyball. The doctor diagnoses her with stable angina. Which of the following drugs is the best choice for long-term control of her angina?

• Answer: E. Propranolol

• Explanation: Propranolol is a beta-blocker effective in treating stable angina due to its ability to reduce myocardial oxygen demand and reduce sympathetic stimulation.

Question 80:

• Question: Which of the following statements is incorrect regarding organic nitrates?

• Answer: B. Unchanged nitrate forms have a longer half-life than dinitrate forms

• Explanation: Unchanged nitrate forms have a shorter half-life than dinitrate forms.

Question 81:

• Question: Which of the following is incorrect about drugs for angina?

• Answer: A. Beta-blockers are highly effective in preventing both stable and Prinzmetal angina

• Explanation: Beta-blockers are effective in treating stable angina but are less effective in treating Prinzmetal angina.

Question 82:

• Question: A 57-year-old man has atrial fibrillation and was initially prescribed quinidine to control the arrhythmia. He was then discharged. His condition improved, but he still experienced occasional arrhythmias. Which of the following drugs could support quinidine in treating atrial fibrillation?

• Answer: C. Procainamide

• Explanation: Procainamide is an antiarrhythmic drug that can be used in combination with quinidine in the treatment of atrial fibrillation.

Question 83:

• Question: Which statement about quinidine is incorrect?

• Answer: C. Decreases digoxin levels in plasma, thus avoiding digoxin toxicity

• Explanation: Quinidine increases digoxin levels in plasma, therefore increasing the risk of digoxin toxicity.

Question 84:

• Question: Which of the following statements is correct regarding antiarrhythmic drugs?

• Answer: E. Drugs like verapamil, nifedipine inhibit slow Ca currents into cells, especially at the sinoatrial and atrioventricular nodes, usually indicated in supraventricular arrhythmias (atrial tachycardia, atrial fibrillation)

• Explanation: Verapamil and nifedipine are calcium channel blockers that inhibit slow Ca currents into cells, especially at the sinoatrial and atrioventricular nodes, commonly indicated in supraventricular arrhythmias.

Question 85:

• Question: A 56-year-old patient being treated for hypertension undergoes a routine health checkup. Blood pressure is recorded as 125/82 mmHg. Laboratory results show LDL-c is 230 and HDL-c is 54. She was then prescribed medication and asked to return for a follow-up in a month. The follow-up results showed LDL-c decreased to 189, but he complained of pain in the calf muscles. Which of the following drugs is most likely responsible for this unwanted side effect?

• Answer: B. Rosuvastatin

• Explanation: Rosuvastatin is a statin drug that can cause muscle pain as a side effect, especially at high doses.

Question 86:

• Question: Which statement about thiazide diuretics is incorrect?

• Answer: A. Inhibit the Na+/Cl- cotransporter in the proximal tubule

• Explanation: Thiazide diuretics inhibit the Na+/Cl- cotransporter in the distal tubule, not the proximal tubule.

Question 87:

• Question: What should be noted when using thiazide diuretics?

• Answer: A. Do not increase the dose for 4-6 weeks

• Explanation: The dose of thiazide diuretics should not be increased too quickly as it can cause side effects such as excessive hypotension, dehydration, and hypokalemia.

Question 88:

• Question: Among all of the following drugs, which one inhibits the Na+/K+/2Cl- cotransporter?

• Answer: B. Furosemide

• Explanation: Furosemide is a loop diuretic that inhibits the Na+/K+/2Cl- cotransporter in the thick ascending limb of the loop of Henle.

Question 89:

• Question: Which of the following statements is correct when using loop diuretics?

• Answer: C. Causes hypokalemia, therefore increasing the effect and toxicity of some drugs such as digoxin, group 3 antiarrhythmics

• Explanation: Loop diuretics can cause hypokalemia, leading to increased effect and toxicity of some drugs such as digoxin, group 3 antiarrhythmics.

Question 90:

• Question: Which ACE inhibitor is not a prodrug?

• Answer: D. Fosinopril

• Explanation: Fosinopril is an ACE inhibitor that is not a prodrug. It is directly absorbed and active in the body.

Question 91:

• Question: The following are true regarding ACE inhibitors, except?

• Answer: A. Increase proteinuria in patients with kidney disease

• Explanation: ACE inhibitors do not increase proteinuria in patients with kidney disease.

Question 92:

• Question: Methyldopa is widely used in?

• Answer: A. Hypertension in pregnancy

• Explanation: Methyldopa is an antihypertensive drug commonly used in pregnant women.

Question 93:

• Question: ACE inhibitors are indicated in the following conditions, except?

• Answer: B. Left ventricular dysfunction

• Explanation: ACE inhibitors are not indicated in left ventricular dysfunction.

Question 94:

• Question: Which of the following drugs has intrinsic sympathomimetic activity?

• Answer: E. Esmolol

• Explanation: Esmolol is a beta-blocker that has intrinsic sympathomimetic activity, meaning it can stimulate beta receptors at low doses.

Question 95:

• Question: A 52-year-old woman being treated for hypertension, hypercholesterolemia, and chronic stable angina complains of severe constipation. Which of the following drugs could be the cause of constipation in the patient?

• Answer: D. Atorvastatin

• Explanation: Atorvastatin is a statin drug that can cause constipation as a side effect.

Question 96:

• Question: What is the mechanism of action of Ezetimide?

• Answer: B. Reduce cholesterol absorption

• Explanation: Ezetimide is a cholesterol-lowering drug that inhibits cholesterol absorption in the gut.

Question 97:

• Question: When using lovastatin, which of the following should be considered?

• Answer: E. All of the above

• Explanation: When using lovastatin, the following should be considered:

• Monitor serum transaminases

• Monitor kidney function

• Monitor hearing

• Monitor blood count regularly

Question 98:

• Question: Which of the following statements about heparin is incorrect?

• Answer: A. Inhibition of antithrombin

• Explanation: Heparin does not inhibit antithrombin. Heparin works by enhancing the activity of antithrombin, helping it to inhibit the activity of thrombin and other clotting factors.

Question 99:

• Question: A 66-year-old man presents to the clinic for a dry cough lasting 5 months. He reports no other symptoms. His medical history includes recent myocardial infarction, for which he was prescribed several medications. He does not smoke and has no history of asthma. Which of the following drugs is responsible for the side effect the patient is experiencing?

• Answer: A. Lisinopril

• Explanation: Lisinopril is an ACE inhibitor, which can cause a dry cough as a side effect.

Question 100:

• Question: (Continued from the previous question) To eliminate the unwanted side effect of the aforementioned drug, the doctor decides to switch the patient to another drug with similar therapeutic benefits and a mechanism of action not much different from the old drug. What is it?

• Answer: C. Losartan

• Explanation: Losartan is an angiotensin II receptor blocker that has a similar mechanism of action to Lisinopril but is less likely to cause a dry cough as a side effect.

Question 101:

• Question: A 16-year-old boy is admitted to the emergency room for severe head injury due to a car accident. Blood pressure is recorded as 220/170mmHg, fundoscopic examination reveals lesions. The doctor prescribes nitroprusside infusion. The patient is kept in the hospital for 72 hours to monitor blood pressure control. However, the doctor finds that he has increasingly severe fatigue and nausea. What is the cause of this condition?

• Answer: A. Formation of thiocyanate from nitroprusside

• Explanation: Nitroprusside can be metabolized to thiocyanate in the body. Thiocyanate can cause side effects such as fatigue, nausea, and neurotoxicity.

Question 102:

• Question: A 63-year-old man has a history of atrial fibrillation. To reduce the risk of stroke, the doctor prescribes an anticoagulant for him. In addition to the therapeutic benefit, this drug is associated with the risk of bleeding. To monitor and adjust the dose appropriately, the doctor asks him to regularly check his prothrombin time. What anticoagulant is prescribed in this case?

• Answer: C. Coumarin

• Explanation: Coumarin is an oral anticoagulant, commonly used to prevent stroke in patients with atrial fibrillation. Coumarin works by inhibiting the synthesis of clotting factors in the liver, leading to reduced clotting ability.

Question 103:

• Question: A 75-year-old patient is admitted to the emergency room after being found unconscious on the floor. His wife reports that he had two strokes in the past and is currently using “a small drug that acts on platelets.” What could this drug be?

• Answer: E. Clopidogrel

• Explanation: Clopidogrel is a platelet aggregation inhibitor, commonly used to prevent stroke in patients with a history of stroke or coronary artery disease.

Question 104:

• Question: A 60-year-old man is being treated for type II diabetes with glyburide. However, blood glucose levels are still poorly controlled, with HbA1c of 7.3%. The doctor decides to prescribe rosiglitazone to augment treatment. What is the mechanism of action of this drug?

• Answer: A. Increase insulin sensitivity in muscle and fat tissues

• Explanation: Rosiglitazone is a thiazolidinedione drug that increases insulin sensitivity in muscle and fat tissues, helping improve blood glucose control.

Question 105:

• Question: A 59-year-old nurse has type II diabetes and a BMI of 30. She is admitted to the emergency room for shock, tachycardia, and tachypnea. She cannot remember her address or phone number to contact in an emergency. She vaguely remembers taking a pill for diabetes this morning. Which of the following drugs could be the cause?

• Answer: C. Glipizide

• Explanation: Glipizide is a sulfonylurea drug that can cause severe hypoglycemia if overdosed.

Question 106:

• Question: Which of the following statements is correct about warfarin?

• Answer: E. All of the above

• Explanation: True statements about warfarin include:

• Completely absorbed through PO, 99% bound to plasma

• Contraindicated in pregnant women

• Narrow therapeutic window, frequent INR monitoring during treatment

• Carbamazepine, barbiturates decrease the effect of warfarin

Question 107:

• Question: Which anticoagulant belongs to the monoclonal antibody group?

• Answer: D. Abciximab

• Explanation: Abciximab is a monoclonal antibody that inhibits platelet aggregation and is used in the treatment of acute coronary artery disease.

Question 108:

• Question: A 45-year-old woman is found to have fasting blood glucose of 147mg/dL and, with the glucose tolerance test, the doctor diagnoses her with type 2 diabetes. She was initially prescribed metformin, but her fasting blood glucose was still above 100mg/dL, so the doctor prescribed glyburide as a replacement. What is the mechanism of action of this drug?

• Answer: A. Increase insulin secretion

• Explanation: Glyburide is a sulfonylurea drug that increases insulin secretion from pancreatic beta cells.

Question 109:

• Question: Which of the following insulins has a long duration of action?

• Answer: E. Determir

• Explanation: Determir is a long-acting insulin that has a duration of action of up to 24 hours.

Question 110:

• Question: Which of the following statements is correct about the use of insulin in diabetes treatment?

• Answer: E. All of the above

• Explanation: True statements about insulin use include:

• One method of use is to combine a short-acting insulin (before meals) and a long-acting insulin (at night before bed)

• Absorption through the UM is faster than SC

• Rotate injection sites to avoid lipohypertrophy/lipoatrophy

• Can cause excessive hypoglycemia and the production of anti-insulin antibodies

Question 111:

• Question: Which of the following drugs is the first-line treatment for obese diabetic patients?

• Answer: B. Metformin

• Explanation: Metformin is a biguanide drug that is first-line treatment for type 2 diabetes, especially in obese patients.

Question 112:

• Question: Which of the following statements is incorrect?

• Answer: E. The effect of thiazolidinediones can be enhanced when used in combination with rifampicin

• Explanation: Rifampicin decreases the effect of thiazolidinediones, not enhances it.

Question 113:

• Question: A 13-year-old patient with diabetes is losing weight very quickly. To quickly control ketoacidosis in this patient, you need to use:

• Answer: C. NPH insulin

• Explanation: NPH insulin is an intermediate-acting insulin, commonly used to control blood glucose in patients with type 1 diabetes.

Question 114:

• Question: Which of the following diabetes medications can improve insulin resistance in tissues?

• Answer: B. Biguanides

• Explanation: Biguanides such as metformin have the effect of increasing insulin sensitivity in tissues, helping to improve blood glucose control in type 2 diabetes patients.

Question 115:

• Question: Which drug and route of administration is incorrect in diabetes treatment?

• Answer: D. Exenatide, PO

• Explanation: Exenatide is a GLP-1 agonist, usually administered subcutaneously, not orally.

Question 116:

• Question: Which of the following statements is correct about DPP-4 inhibitors?

• Answer: C. Does not affect cytochrome oxidase in the liver

• Explanation: DPP-4 inhibitors do not affect cytochrome oxidase in the liver, so they have fewer drug interactions with drugs metabolized through the liver.

Question 117:

• Question: A 76-year-old man has long-standing atrial fibrillation and has been well-controlled with amiodarone and diltiazem. Recently, he has been experiencing palpitations. After examination, the doctor prescribed digoxin. Which of the following is the mechanism of action of digoxin?

• Answer: A. Decreases intracellular Na+ and increases intracellular K+

• Explanation: Digoxin is a drug for treating atrial fibrillation that reduces intracellular Na+ levels and increases intracellular K+ levels, helping to inhibit AV conduction and control heart rate.

Question 118:

• Question: Which of the following drugs causes coronary steal syndrome?

• Answer: A. Dipyridamole

• Explanation: Dipyridamole is a peripheral vasodilator that can cause coronary steal syndrome in patients with coronary artery disease.

Question 119:

• Question: Which of the following drugs worsens angina except?

• Answer: B. Dipyridamole

• Explanation: Dipyridamole is a vasodilator, which can help reduce cardiac workload and decrease angina.

Question 120:

• Question: A 47-year-old female patient is hospitalized for the treatment of acute myocardial infarction. Previously, she was prescribed digoxin for atrial fibrillation. She also has hypertension but is not currently being treated. Before discharge, the doctor prescribes an additional drug to control hypertension. After returning home and taking the medication as prescribed by the doctor, she experiences a dangerous arrhythmia and is promptly rescued. Which of the following drugs prescribed by the doctor for hypertension could potentiate the effect of digoxin that the patient is taking?

• Answer: B. Hydrochlorothiazide

• Explanation: Hydrochlorothiazide is a thiazide diuretic that can increase digoxin levels in plasma, therefore increasing the risk of digoxin toxicity.

Note: The information above is for reference only. Please consult a healthcare professional for accurate and complete advice.