UWorld-Pharmacology

Question 1

A person gardening suddenly gets blurred vision, dilated (and non-reactive to light) pupils, flushed skin and dry mouth. What is the toxin and the condition?

Answer 1

Jimson Weed (belladona alkaloids=toxin)
produces atropine-like syndrome (flushing, dry/hot skin, mydriasis, loss of accomodation, urinary retention, tachycardia, vasoconstriction, bronchodilation, etc.)

Question 2

mechanism of action of probenecid and when you would prescribe it

Answer 2

decreases renal reabsorption of uric acid, used –along with xanthine oxidase inhibitors (allopurinol and febuxostat) to treat chronic gout (not acute: NSAIDs and colchicine for acute)

Question 3

pleocytosis in CSF upon lumbar puncture suggests you should give what treatment

Answer 3

ampicillin for Listeria monocytogenes

Question 4

what is the best drug to treat hypertension in a patient with chronic ischemic myocardial failure

Answer 4

ACE inhibitors;
in addition to lower BP, they prevent myocardial remodelling and prevent deterioration of ventricular contractile function

Question 5

name three 3rd generation aromatase inhibitors;

what do they treat

Answer 5

anastrozole, letrozole and exemestane;

treats breast cancer in postmenopausal women with breast cancer

Question 6

what endogenous inflammatory mediator increases the thermoregulatory set point in the hypothalamus (note: pyrogenic cytokines act by increasing levels of this mediator)

Answer 6

PGE2

Question 7

most commonly used medication for osteoporosis

Answer 7

bisphosphanates (i.e. alendronate, risedronate, ibandronate)

note: bisphosphonates are structural analogues of pyrophosphate

Question 8

after a subarachnoid hemorrhage what drug would you want to give to prevent cerebral vasospasm that can result from the metabolites released from the hemorrhage

Answer 8

nimodipine: a dihydropryridine calcium channel blocker that acts in the cerebral vasculature

Question 9

what are the two ways that N-acetylcysteine helps treat acetominaphen overdose

Answer 9

1. acts like a substitute for glutathione to bind NAPQI

2. provides sulfhydrul groups to sulfate and thereby eliminate acetominaphen

Question 10

if a patient has been given too high of a dose of nitroprusside and develops altered mental status what should be given next and why

Answer 10

sulfur (in the form of sodium thiosulfate);
this patient has cyanide poisoning from too much nitroprusside; sodium thiosulfate helps liver rhodanase add sulfur to cyanide for elimination in the form of thiocyanate

Question 11

etanercept, infliximab, and certolizumab pegol all act to inhibit activity of what agent?
how do they each do this?

Answer 11

inhibition of TNF-alpha activity:
-etanercept is a decoy (fusion protein of TNF-alpha and Fc region of IgG)

• infliximab is a monoclonal antibody against TNF-alpha
• certolizumab pegol is a pegylated monoclonal antibody against TNF-alpha (lacks Fc region of IgG so it prevents complement and cell-mediated cytotoxicity)

Question 12

first line therapy for isolated hypertension in a non-diabetic vs. first line treatment for HTN in a diabetic patient

Answer 12

1st line for HTN alone= thiazides and dihydropyridine Ca2+ channel antagonists

1st line for HTN in diabetic= ACE-Is and ARBs

Question 13

is macrophage elastase or neutrophil elastase inhibited by alpha1-antitrypsin

Answer 13

neutrophil elastase is inhibited, but macrophage elastase is not

Question 14

most effective drug at raising HDL levels;

most effective drug at lowering LDL levels

Answer 14

niacin;

statins

Question 15

what drug is metabolized to form phenobarbitol

Answer 15

primidone

Question 16

a patient treated for depression now has flushing, hypotension, tachycardia and premature ventricular beats; what would you give to treat the patient

Answer 16

NaHCO3
this patient has TCA-induced arrhythmia (blockade of Na+ fast channels =>prolonged QRS and/or QT, dysrrhythmia); NaHCO3 can correct prolonged QRS, reverse hypotension and treat ventricular dysrhythmias