1.
Which of the following beta-blockers would cause maximum hypoglycemia?
Correct Answer
D. Labetalol
Explanation
Labetalol is a non-selective beta-blocker that blocks both beta-1 and beta-2 adrenergic receptors. Beta-2 receptors are found in the liver and pancreatic islet cells, where they play a role in glycogenolysis and gluconeogenesis. By blocking these receptors, labetalol can impair the body's ability to raise blood glucose levels, leading to hypoglycemia. The other beta-blockers listed, such as timolol, metoprolol, atenolol, and propranolol, are more selective for beta-1 receptors and have less effect on blood glucose levels. Therefore, labetalol would cause the maximum hypoglycemia compared to the other options.
2.
A 32-y/o M complained to his Dr. of fatigue, insomnia, loss of libido and depression. The man, diagnosed with chronic classic migraine three week previously, started prophylactic treatment with a drug which reduced the frequency of the attacks. Which of the following drugs was he most likely taking?
Correct Answer
C. Propranolol
Explanation
The patient's symptoms of fatigue, insomnia, loss of libido, and depression are consistent with side effects of beta-blockers, which are commonly used for prophylactic treatment of migraines. Among the options provided, propranolol is a beta-blocker commonly used for migraine prophylaxis. Therefore, the patient is most likely taking propranolol.
3.
A 25-year-old man is undergoing laparoscopic surgery for pheochromocytoma under general anesthesia. After resection of tumor, he suddenly develops a heart rate of 140 bpm. He has a history of developing cardiac arrhythmias on 3 previous occasions. Which of the following short acting beta blockers would be suitable at this point?
Correct Answer
D. Esmolol
Explanation
Esmolol would be suitable at this point because it is a short-acting beta blocker that can quickly control the patient's elevated heart rate. This is important in the given scenario as the patient suddenly developed a heart rate of 140 bpm after tumor resection. Esmolol's short duration of action allows for rapid onset and offset of its effects, making it a good choice in situations where immediate control of heart rate is necessary. Propranolol, Sotalol, Pindolol, and Metoprolol are not short-acting beta blockers and may not provide the same rapid control of heart rate.
4.
A 40-year-old female visits the internal medicine clinic with complaints of occasional palpitations and fainting. History reveals she is hypertensive, and is currently on an anti-hypertensive regimen including an adrenergic blocker, a diuretic, and an ACE inhibitor. On investigation her ECG reveals a prolonged QT interval. Which of the following drugs was she most likely taking?
Correct Answer
D. Sotalol
Explanation
The patient's history of hypertension and the medications she is currently taking suggest that her prolonged QT interval is likely due to the use of Sotalol. Sotalol is a non-selective beta blocker with Class III antiarrhythmic properties, commonly used to treat arrhythmias. It has been associated with prolongation of the QT interval, which can increase the risk of torsades de pointes, a potentially life-threatening ventricular arrhythmia. The other options, Carvedilol, Prazosin, Labetalol, and Doxazosin, do not typically cause QT interval prolongation.
5.
A 52-year-old man comes to his physician with a chief complaint of difficulty of urination. Physical examination shows a blood pressure of 132/80 mmHg, heart rate is 68 bpm and a slightly enlarged prostrate. Which of the following is the most appropriate agent to treat his condition?
Correct Answer
E. Doxazosin
Explanation
Doxazosin is the most appropriate agent to treat the man's condition because he has an enlarged prostate, which is likely causing his difficulty with urination. Doxazosin is an alpha-1 blocker that helps relax the smooth muscles in the prostate and bladder neck, allowing for easier urine flow. Labetalol, Atenolol, and Metoprolol are beta blockers used to treat high blood pressure and would not directly address the man's urinary symptoms. Phentolamine is an alpha blocker used for other conditions, such as erectile dysfunction, but is not commonly used for urinary symptoms.
6.
A 34-year-old man is rushed to the emergency department with severe palpitation and anxiety. His blood pressure is found to be 200/110 mmHg. History reveals noncompliance for last two days with beta blockers that the patient had been taking for the past 6 months. What is the most likely underlying cause of the latest complication in this patient?
Correct Answer
A. Upregulation of beta-receptors
Explanation
The most likely underlying cause of the latest complication in this patient is upregulation of beta-receptors. This is because the patient had been taking beta blockers for the past 6 months, which would have blocked the beta-receptors. Noncompliance with the medication would lead to the rebound effect of upregulation of beta-receptors, causing severe palpitation and anxiety. This upregulation would increase the sensitivity of the beta-receptors to sympathetic stimulation, leading to increased heart rate and blood pressure.
7.
The following diagram shows the determinants of blood pressure. Analyze the diagram and identify the site, where prazosin produces its effect by virtue of its direct action:
Correct Answer
D. D
Explanation
The diagram shows the determinants of blood pressure, and the site where prazosin produces its effect by virtue of its direct action is indicated by option D. However, without further information or context about the diagram and the effects of prazosin, it is difficult to provide a more detailed explanation.
8.
A 22-year-old previously healthy woman was brought to the emergency room because she had collapsed during jogging. She denied orthopnea, paroxysmal nocturnal dyspnea, chest pain or edema. Her younger brother was known to have had two episodes of syncope after exertion. The ECG indicated left ventricular hypertrophy and the echocardiogram showed an asymmetric septal hypertrophy. Which of the following drugs would be most appropriate for this patient?
Correct Answer
C. Metoprolol
Explanation
The patient is presenting with symptoms suggestive of hypertrophic cardiomyopathy (HCM), which is characterized by left ventricular hypertrophy and asymmetric septal hypertrophy. Beta-blockers, such as metoprolol, are the mainstay of treatment for HCM as they help to reduce symptoms and improve exercise tolerance by decreasing heart rate and contractility. Prazosin, doxazosin, and phentolamine are alpha-blockers and are not typically used in the treatment of HCM. Timolol is a non-selective beta-blocker and may be effective in reducing heart rate and contractility, but metoprolol is the preferred beta-blocker for HCM due to its selective beta-1 blocking properties.
9.
A 51-year-old woman presents with a one month history of palpitations, insomnia, nervousness, fatigue, diarrhea and heat intolerance. The physcal examination reveals hyperreflexia, lid lag and mild tremor. Vital signs are: blood pressure 160/65, heart rate 95 bpm. Which of the following drugs should be included in an appropriate therapeutic management of this patient?
Correct Answer
B. Propranolol
Explanation
Propranolol should be included in the therapeutic management of this patient because her symptoms and physical examination findings are consistent with hyperthyroidism. Propranolol is a non-selective beta-blocker that can help alleviate symptoms such as palpitations, tremor, and nervousness by blocking the effects of excess thyroid hormones on the heart and peripheral tissues. It can also help control the patient's elevated heart rate and blood pressure.
10.
A 56-year-old man, recently diagnosed with exertional angina, started a therapy with propranolol. Which of the following cardiovascular parameters was most likely decreased in this patient?
Correct Answer
C. Cardiac ejection fraction
Explanation
Propranolol is a beta-blocker medication commonly used to treat angina. It works by blocking the beta receptors in the heart, which reduces the heart rate and contractility. Cardiac ejection fraction is a measure of the percentage of blood pumped out of the heart with each contraction. Since propranolol decreases the contractility of the heart, it is likely to decrease the cardiac ejection fraction.
11.
A new autonomic drug was tested on healthy volunteers. Subjects were treated with saline or with the drug and then their heart rate was measured under resting or exercise conditions. The results were the following:
The tested drug most likely was a/an:
Correct Answer
A. Beta-blocker
Explanation
Based on the information provided, the tested drug is most likely a beta-blocker. Beta-blockers are known to reduce heart rate and are commonly used to treat conditions such as high blood pressure and heart disease. In this study, the drug was tested on healthy volunteers, and their heart rate was measured under resting or exercise conditions. If the drug caused a decrease in heart rate, it suggests that it is a beta-blocker, as these drugs are known to slow down the heart rate.
12.
Metoprolol was given TM to several dogs during a lab experiment. One hour later each dog received an autonomic drugs and the effects of that drug were recorded. Which of the following drug-induced effects was most likely best counteracted by metoprolol pretreatment?
Correct Answer
E. Dobutamine-induced tachycardia
Explanation
Metoprolol is a beta-blocker that works by blocking the effects of adrenaline on the beta receptors in the heart, thereby reducing heart rate and blood pressure. Dobutamine is a drug that stimulates beta receptors, leading to an increase in heart rate. Given that metoprolol counteracts the effects of adrenaline on the heart, it is most likely to best counteract the tachycardia (increased heart rate) induced by dobutamine.