A 62-year-old man presents to the clinic with rashes all over his body and painful joints. Last month, he was diagnosed with arrhythmia. He is taking one medication for it. Laboratory tests reveal anti-histone antibodies. Which of the following drugs is most likely responsible for this condition? A-Hydralazine B-Metoprolol C-Propranolol D-Sotalol E-Verapamil Answer The answer […]
pharmacology
Repeated USMLE Questions Step 1- 268
A 19-year-old man presents to the clinic with a complaint of tremors and incoordination. Serum transaminases are slightly elevated. Slit lamp examination shows brownish corneal deposits. What is the element directly involved in this condition? A-Arsenic B-Lead C-Copper D-Iron E-Zinc Answer This is a presentation of Wilson’s disease in which cellular copper transport is disturbed […]
Medical Question of the Day- 33
Workers in the aniline dye industry are more susceptible to bladder cancer than general population. Meanwhile, studies show that animals, when exposed to beta-naphthylamine develop liver cancer but not bladder cancer. What is the most likely explanation of this finding? A-Metabolism of beta-naphthylamine by human cytochrome 450 system in the liver B-Detoxification of beta-naphthylamine by […]
Repeated USMLE Questions Step 1- 266
A 12-year-old girl visits her physician for follow up after treatment with methotrexate for acute lymphoblastic leukemia. Stool analysis reveals blood in stool. Her platelet count is very low. Which of these substances should be administered immediately? A-Vitamin K B-Leucovorin C-Deferoxamine D-Amitriptyline E-Penicillamine Answer This is a case of methotrexate toxicity. Leucovorin is the active […]
Repeated USMLE Questions Step 1- 263
A 48-year old man presents to the emergency room with severe headache and blurred vision. His blood pressure is 230/140. Ophthalmologic examination reveals blurred optic discs with indistinct margins. An intravenous drip of nitroprusside is started. What is the mechanism of action of this medication? A- Alpha adrenergic antagonist B- Beta adrenergic antagonist C- Ganglion […]
Repeated USMLE Questions Step 1- 257
A 54-year-old woman with a history of hypothyroidism, hypertension, depression and joint pains develops fatigue, facial rash, headaches, dizziness, confusion, diarrhea and personality changes. She takes levothyroxine, hydralazine, amitriptyline and ibuprofen. Which of these drugs is most likely responsible for this patient new symptom? A- Levothyroxine B- Hydralazine C- Amitriptyline D- Ibuprofen Answer This patient […]
Repeated USMLE Questions Step 1- 254
A 4-year old girl is brought to the clinic by her mother complaining of fever and abdominal pain since yesterday. Today, she looks uncomfortable during micturition. On examination, her temperature is 99.4, her pulse is 100/min. and her suprapubic area is soft and tender. Her blood analysis shows increased neutrophils. Her urinalysis is positive for […]
Repeated USMLE Questions Step 1- 253
A 67-year old man is brought to the emergency room by his colleagues for a possible heart attack. One hour ago, he felt excruciating chest pain, shortness of breath and nausea. ECG shows elevation of ST segment in leads 11, 111 and aVF. Therapy is initiated and the patient starts feeling better. ER physician explains […]
Repeated USMLE Questions Step 1- 172
A 22-year-old woman presents to the clinic for a recurrent urinary tract infection. She is prescribed trimethoprim/sulfamethoxazole. What is the mechanism of action of this antimicrobial drug? A- Inhibition of bacterial wall synthesis B- Inhibition of folic acid synthesis C- Inhibition of bacterial protein synthesis D- Inhibition of mycolic acid synthesis E- Inactivation of bacterial […]
Repeated USMLE Questions Step 1- 167
A 24-year old woman is diagnosed with vaginal trichomoniasis. She is prescribed metronidazole. She is breastfeeding her 3 month old boy. What is the appropriate advice for this patient concerning the use of metronidazole during breastfeeding? A-Stop breast feeding and replace it with formula for 3 months B-Stop metronidazole and choose another less effective drug […]