Repeated USMLE Questions Step 1- 349



Q- Which of the following agents reduce the blood levels of certain drugs through its action on hepatic P450 system?

A- Grapefruit juice

B- Guava juice

C- Kava

D- St. John’s wart

D- St. John’s wart induces the metabolism of some drugs by stimulation of P450 enzyme activity while the others inhibit it. 



Q- Which of the following is the most common cause of nasal obstruction and bleeding in adolescents?

A- Angiofibroma

B- Nasal cancer

C- Nasal polyps

D- Papilloma

A- Angiofibroma: Juvenile angiofibroma is the most common vascular tumor in teenage boys and young adults. 



Q- What is the most common injury resulting from wearing a heavy backpack for a long time?

A- Costoclavicular syndrome

B- Frozen shoulder

C- Rotator cuff injury

D- Shoulder dislocation

A- Costoclavicular syndrome: Wearing a backpack for a long time leads to compression of subclavian vein and artery causing cyanosis, pain and paresthesia. 



2 thoughts on “Repeated USMLE Questions Step 1- 349”

Leave a Comment