USMLE Pharmacology Question Base

A neurophysiologist is studying the consequences of diminished brain perfusion in an experimental animal. The carotid artery is occluded, and brain function is monitored by positron emission tomography. Which of the following drugs would be most effective in reversing the change in heart rate produced by the experimental occlusion?

A former drug abuser visits his physician to ask pain medications for a legitimate back pain. The physician takes the history of drug abuse into account. Which of the following medications has the greatest potential for abuse?

A 67-year-old man presents to the emergency department with shaking chills and a temperature of 38.0 ºC (101 ºF). Laboratory examination reveals a hematocrit of 23%, and urine tests are positive for blood. The patient states that he is taking only one medication for his “infection”. Which of the following drugs most likely caused the appearance of these signs and symptoms in this patient?

A 55-year-old diabetic man is brought to the emergency department in an unresponsive state. The following laboratory values are obtained:

Pco₂: 19 mm Hg
Bicarbonate:11 mEq/L
pH: 6.9

which of the following is the most appropriate immediate treatment for this patient?

Genetic analysis of a female infant with a broad, enlarged neck demonstrates an XO karyotype. When the child reaches puberty, hormone replacement therapy should be started with which of the following agents?

A 48-year-old type 2 diabetic patient on daily extended-release glipizide presents with complaints of polyuria and polydipsia. Laboratory evaluation reveals a blood glucose of 192 mg/dL. She states that her diabetes had been well controlled and that she had been symptom-free for the past 10 years. Recently, however, she began taking medications for hypertension. Which of the following antihypertensive drugs is the most likely taking?

A patient is administered a skeletal muscle relaxant prior to abdominal surgery. The patient soon begins to exhibit hypotension, bronchospasm, and excessive bronchial and salivary secretions. Which of the following skeletal muscle relaxants did this patient most likely receive?

A 41-year-old diabetic woman presents to her physician complaining of gastrointestinal distress and heartburn, particularly after meals. Which of the following drugs should her physician prescribe to relieve her symptoms?

A 48-year-old homeless man with a history of alcoholism ingests a bottle of antifreeze and presents to the emergency department obtunded but with intact vision. Which of the following is the most appropriate pharmacotherapy?

A patient was administered mecamylamine during surgery. This drug will most likely cause which of the following responses?

A 34-year-old man with a long history of asthma is referred to a pulmonologist. The physician decides to prescribe zileuton. The mechanism of action of this drug is to

A 45-year-old man presents to the emergency department with severe pneumonia. He recently returned from a business trip, and has a history of smoking and alcohol use. An x-ray film shows extensive consolidation affecting portions of each lung. Culture on charcoal yeast extract medium grows out a small gram-negative bacterium. Which of the following antibiotics is he most appropriate treatment for this patient?

A 62-year-old white man complains of left thigh and leg pain and swelling that are exacerbated by walking. One week earlier, the patient underwent cardiac catheterization. The patient is currently vacationing and has spent the past 28 hours in a car. Which of the following drugs, which might be prescribed in this instance, works by inhibiting the enzyme epoxide reductase?

Two alpha-adrenergic antagonists (Drug A and B) decrease blood pressure by the same amount following IV administration at the following doses:

Drug A: 120 mg
Drug B: 15 mg

Which of the following drugs used to treat rheumatoid arthritis is the extracellular portion of the tumor necrosis factor (TNF) receptor fused to Fc region of human IgGI?

A 53-year-old man comes to the physician because of tingling in his feet and recurrent blurry vision. He is an obese man who rarely exercises and who eats an excessive amount of fatty, high-caloric food. He takes no medications. A fasting plasma glucose level is 169 mg/dL on this visit and 172 mg/dL on a subsequent visit. Which of the following drugs used in the treatment of hiw condition will increase muscle uptake of glucose and decrease hepatic glucose production but not stimulate secretion of insulin?

A 32-year-old woman who is 36 weeks pregnant is told during a prenatal appointment that her fetus is in a breech presentation. An external cephalic version (manually turning the fetus from the outside) is scheduled for the following week. For this procedure, the uterus must be relaxed. Which of the following drugs would be most appropriate for achieving this result?

A patient with essential hypertension is starting diuretic therapy. He has a history of calcium oxalate renal stones. Which of the following diuretics would be most appropriate for this patient?

A 64-year-old man presents to his family physician complaining of difficulty urinating and “dribbling” at the end of urination. The physician diagnoses benign prostatic hyperplasia. Which of the following drugs would be most appropriate for treating this man’s condition?

A 33-year-old man receiving chemotherapy for testicular carcinoma develops signs of renal tubular damage. Which of the following drugs is most likely responsible for this nephrotoxicity?

A 30-year-old woman with a history of tonic-clonic seizures complains of double vision, thickened gums, and growth of facial hair since starting a new medication. Which of the following anticonvulsant medications is most likely responsible for her symptoms?

A 52-year-old man with peptic ulcer disease has been on drug therapy for 3 months and has noticed changes in his bowel habits, increasing headaches, dizziness, skin rashes, loss of libido, and gynecomastia. Which of the following drugs is most likely responsible for these side effects?

A 48-year-old smoker with deep venous thrombosis is given heparin. Heparin achieves its anticoagulant activity by binding to which of the following substances?

A pharmacology professor is teaching his class about the actions of different drugs on vessels. A certain drug produces vasodilation by increasing cGMP in the smooth-muscle cells of arterioles. Which of the following drugs has this mechanism of action?

A 33-year-old woman goes to the physician for a minor outpatient procedure. The physician wants to use a long-duration ester for a local anesthetic. Which of the following agents should be used?

A 58-year-old man presents with difficulty initiating movements and a resting tremor. On physical examination, his face appears expressionless and he has a slow shuffling gait. He is started on selegiline. Which of the following is the mechanism of action of this drug?

A 46-year-old woman visits her podiatrist to have several bunions removed from her right foot. She chooses conscious sedation rather than general anesthesia for this procedure. She is given IV midazolam to supplement the local anesthetics that are injected into her foot. Midway through the surgery, she suddenly becomes agitated and combative and exhibits involuntary movements. The anesthesiologist determines that she is having a paradoxical reaction to the midazolam and immediately administers

A 47-year-old man presents with acute pain in his big toe. Laboratory tests reveal a uric acid level of 10 mg/dL. He is started on medication (Drug 1). several days after the resolution of the acute attack, he is started on a second medication (Drug 2). Drug 2 decreases both the serum and urine levels of uric acid. Which of the following is Drug 2?

An 82-year-old woman presents to her physician complaining of difficulty sleeping and problems coping throughout the day since the recent death of her husband. She requests a medication that will help her through this time of her life. Her physician prescribes oxazepam. The most likely rationale behind prescribing this drug is that oxazepam

A new antibiotic is being tested in clinical trials. The following pharmacokinetic parameters have previously been determined:

Clearance = 100 mL/min
Volume of distribution (V­_d) = 50 L
Half-life = 3 hours

Assuming that the drug is being administered intravenously, what loading dose (LD) should be given to a patient to quickly obtain a plasma concentration of 10 mg/L?

A 74-year-old woman with multiple myeloma is being treated with high doses of doxorubicin (Adriamycin). She has also received cyclophosphamide and prednisone recently. During an examination, the physician should check the patient for which of the following?

A 55-year-old woman is receiving chemotherapy for non-Hodgkin lymphoma. Several days after a treatment, she notices blood in her urine. Which of the following antineoplastic drugs is most likely responsible for this side effect?

A continuous IV infusion of lidocaine is given to a 70-kg patient with cardiac arrhythmias. The pharmacokinetic parameters for lidocaine are as follows: clearance (CL) = 9 mL/min/kg, volume of distribution (V_d) = 70 L, half-life =2 hours. How long will it take for drug levels to reach 87.5% of steady state?

A 33-year-old with a history of asthma is being treated for symptoms of hypertension. Which of the following beta-blockers would be an appropriate therapy for this patient?

A worried mother complains to her pediatrician that both she and her 6-year-old son’s teacher have noticed that the child has become inattentive. She states that her son frequently stops what he is doing and “stares blankly into space” before resuming his activities. Electroencephalography reveals a 3/second spike and slow wave pattern of discharges. Which of the following agents would most effectively treat this child’s disorder?

A 58-year-old woman arrives at her physician’s office complaining of moderate anxiety. Which of the following drugs will help relieve her anxiety, with a minimum of unwanted sedative side effects?

A 62-year-old woman is being prepared for cardiac bypass surgery. Before she is intubated, she is given a skeletal muscle relaxant that causes her to have muscle fasciculations prior to muscle relaxation. Which of the following drugs was most likely administered?

A medical professor is cleaning out her files and comes across an old case report about a 56-year-old man with hypertension who had been treated with reserpine for many years. On a routine blood pressure check, the patient was found to have an increase in blood pressure. When told about this finding, the patient reported that since his last visit he had taken an additional medication, and he admitted to recreational drug use. Which of the following medications was most likely responsible for his increase in blood pressure?

A 26-year-old woman undergoing surgery is given an inhalant anesthetic. She is also given an IV dose of succinylcholine. Within minutes, she develops a heart rate of 124/min and increasing core body temperature. Which of the following is the mechanism of action of the drug of choice for this patient’s condition?

A 5-year-old boy with no previous medical history is brought to the emergency department by his mother because he accidentally ingested a large dose of rat poison. He is conscious but appears quite agitated. On physical examination, his blood pressure is 100/70 mm Hg and pulse is 90/min. laboratory results are significant for an elevated prothrombin time (PT) but a normal partial prothrombin time (PTT). Which of the following is the most appropriate pharmacotherapy?

A 24-year-old migrant farm worker is rushed to a nearby emergency department after an accident exposure to parathion. He is in respiratory distress and is bradycardic. Which of the following drugs can be given to increase the activity of his acetylcholinesterase?

A 24-year-old woman attempts suicide by ingesting 50 acetaminophen tablets. She is rushed to the emergency department. Which of the following treatments would the attending physician most likely order?

The pharmacokinetic properties of a new drug are being studied in normal volunteers during phase I clinical trials. The volume of distribution and clearance determined in the first subject are 80 L and 4 L/hr, respectively. The half-life of the drug in this subject is approximately

Drug X has a t_1/2 of 4 hours and is renally eliminated. After elimination of one kidney, how long (in hours) would it take for Drug X to reach steady state?

A 57-year-old smoker with a long history of chronic obstructive lung disease presents to the physician with a blood pressure of 150/95 mm Hg. Which of the following antihypertensives is contraindicated in this patient?

Prothrombin your elderly patient has been on the same dose of levothyroxine for several years. For the last year, however, his thyroid stimulating hormone (TSH) level has been high on two occasions and low on the most recent test. You examine a list of your patient’s medications and suspect which of the following is the culprit behind the fluctuating TSH levels?

A 70-year-old man complains of chronic heartburn. It is painful for him to bend over, and he sleeps on a wedge-shaped pillow to try to reduce the burning sensation. Which of the following agents would be the most efficacious in reducing his symptoms?

A man is taking phenelzine for atypical depression. He goes to a party and consumes a few bottles of beer and some aged cheese and crackers. Later that evening, he develops a headache so severe he needs to go to the hospital. He is found to have a blood pressure of 210/100 mm Hg. The emergency room physician explains to him that because he is taking this medication, he should not have consumed those particular foods at the party because they contain which of the following types of substances?