USMLE® Step 1 & 2

Kaplan USMLE Step 2: What caused 72-year-old’s withdrawal syndrome?

. 4 MIN READ

If you’re preparing for the United States Medical Licensing Examination® (USMLE®) Step 2 exam, you might want to know which questions are most often missed by test-prep takers. Check out this example from Kaplan Medical, and read an expert explanation of the answer. Also check out all posts in this series.

Free study aid when you join the AMA

Medical students who become AMA members can select a free gift from a variety of powerful study aids for the USMLE and COMLEX-USA tests.

Supporting you today as a medical student. Protecting your future as a physician.

A 72-year-old man is brought to the emergency department because of heart palpitations and headache. His past medical history includes essential hypertension. He normally takes a variety of antihypertensive medications, but he ran out of "one or two of them" last night. His blood pressure is 210/120 mm Hg. Ophthalmoscopic examination shows arteriovenous nicking and papilledema. Urinalysis shows proteinuria. His systolic blood pressure readings in the past have not been greater than 175 mm Hg. The physician suspects that this patient's current condition is caused by the sudden withdrawal of a medication. Which of the following is the most likely medication?

A. Atenolol

B. Clonidine

C. Felodipine

D. Hydrochlorothiazide

E. Lisinopril

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The correct answer is B.

Clonidine is a centrally acting alpha-adrenergic agonist that causes reduced sympathetic outflow from the central nervous system and can be used as a treatment-refractory anti-hypertensive agent. If stopped abruptly, clonidine can cause a withdrawal syndrome with severe rebound hypertension (choice B) and therefore needs to be tapered slowly.

Choice A. Beta-blockers such as atenolol can also cause a withdrawal syndrome if they are stopped abruptly due to increased sympathetic activity. There may be a rise in heart rate and blood pressure, but it is unlikely to cause profound rebound hypertension like clonidine.

 

 

Did you answer the question correctly?

Log in to get tips to remember and learn more from Kaplan Medical about why the other answer choices can be eliminated.

AMA membership has its advantages

  • Access education programs and study guides to help you thrive.
  • Distinguish yourself with AMA leadership opportunities.
  • Enjoy exclusive perks and savings.

Not a member? Become a member now.

FEATURED STORIES FOR MEDICAL STUDENTS