Test your basic knowledge |

USMLE Step 1 Pharmacology

Subjects : health-sciences, usmle-step-1

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What are two types of drugs that interfere with the action of Sucralfate and why?
1. Tolbutamide 2. Chlorpropamide 3. Glyburide 4. Glipizide
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.
Prevents the release of ACh - Which results in muscle paralysis.
Inhibits Viral DNA polymerase

2. Which of the following would atropine administration cause? Hypothermia - bradycardia - excess salivation - dry flushed skin - or diarrhea
Dry flushed skin - due to inhibition of sympathetic post - ganglionic blockade on muscarinic receptors of sweat glands. All others are opposite of What would be expected.
Succinylcholine
Atropine would also block the receptors in the ciliary muscle - causing an impairment in accommodation (cycloplegia).
Diarrhea

3. Aztreonam ________ to penicillinase
is resistant
Depolymerizes microtubules - impairing leukocyte chemotaxis and degranulation.
Acts as a wide spectrum carbapenem
- inhibits HGPRT (pur. Syn.) - Luk - Lymph

4. What is the effect of the Glitazones in diabetes treatment?
Inhibits xanthine oxidase - decresing conversion of xanthine to uric acid.
- Penicillamine
Increase target cell response to insulin.
1. Weight gain 2. Hepatotoxicity (troglitazone)

5. Explain potency in relation to full and partial agonists(2).
Foscarnet = pyroFosphate analog
Ceftriaxone
- partial agonist can have increased - decreased - /A21or equal potency as full agonist. - Potency is an independent factor.
- Vinca alkaloids(inhibit MT) - Paclitaxel

6. What is the category of drug names ending in - ane (e.g. Halothane)
Inhalational general anesthetic.
Amphotericin B - Nystatin - Fluconazole/azoles
- Halothane - Valproic acid - acetaminophen - Amantia phalloides
Inhibit intestinal bursh border Alpha - glucosidases; delayed hydrolysis of sugars and absorption of sugars leading to decresed postprandial hyperglycemia.

7. List the mechanism - clinical use - & toxicity of Tamoxifen.
Acetylcholinesterase; ACh is broken down into choline and acetate.
- Cimetidine - ketoconazole - grapefruit juice - erythromycin - INH - sulfonamides
- Estrogen receptor antagonist - Breast CA - increased endometrial CA risk
TMP- SMZ (DOC) - aerosolized pentamidine

8. What are common toxicities associated with Macrolides? (4)
GI discomfort - Acute cholestatic hepatitis - Eosinophilia - Skin rashes
- Alkalates DNA - CML - Pulmonary fibrosis hyperpigmentation
- NaHCO3
1. Skin rash 2. Agranulocytosis (rare) 3. Aplastic anemia

9. What is Fluconazole specifically used for?
Cryptococcal meningitis in AIDS patients and Candidal infections of all types
Modification via Acetylation - Adenylation - or Phosphorylation
first dose orthostatic hypotension - dizziness - headache
No - it inhibits the release of Nor Epi

10. Does Ampicillin or Amoxicillin have a greater oral bioavailability?
Hypersensitivity reactions
Peptic ulcer disease.
Ipratropium
AmOxicillin has greater Oral bioavailability

11. Nifedipine has similar action to?
Hexamethonium is a nicotinic antagonist - and thus is a ganglionic blocker.
Useful in muscle paralysis during surgery or mechanical ventilation.
INH: Injures Neurons and Hepatocytes
Nitrates

12. What is the receptor affinity and clinical use of isoproterenol?
Rash - Pseudomembranous colitis
Well tolerated in general but occasionally - Nephrotoxicity - Ototoxicity - Thrombophlebitis - diffuse flushing='Red Man Syndrome'
1. Infertility (pulsatile) 2. Prostate cancer (continuous: use with flutamide) 3. Uterine fibroids
It affects beta receptors equally and is used in AV heart block (rare).

13. Which diuretics cause alkalosis?
Bind cell membrane - disrupt osmotic properties - Are Cationc - Basic and act as detergents
Lovastatin - Pravastatin - Simvastatin - Atorvastatin
loop diuretics - thiazides
WEPT: Warfarin affects the Extrinsic pathway and prolongs the PT.

14. What are toxic side effects for Metronidazole?
Enterobacter
hypertension - CHF - diabetic renal disease
prevention of nodal arrhythmias (SVT)
Disulfiram - like reaction with EtOH - Headache

15. Hydrochlorothiazide - mechanism?
Inhibt Assembly of new virus by Blocking Protease Enzyme
Nifedipine - Verapamil - Diltiazem
- Penicillamine
Inhibits NaCl reabsorption in the early distal tubule. Decreases Ca2+ excretion.

16. What is the clinical utility of cocaine?
Saquinavir - Ritonavir - Indinavir - Nelfinavir
Tricyclic antidepressant.
The only local anesthetic with vasoconstrictive properties.
- Methotrexate - 5 FU - 6 mercaptopurine

17. Ibutilide - toxicity?
Rifampin - Ethambutol - Streptomycin - Pyrazinamide - Isoniazid (INH)
torsade de pointes
- Sulfonamides - INH - ASA - Ibuprofen - primaquine - nitrofurantoin /- pyrimethamine - chloramphenicol
Milk or Antacids - because divalent cations inhibit Tetracycline absorption in the gut

18. What is the category of drug names ending in - oxin (e.g. Digoxin)
Malaria (P. falciparum)
Inhibits formation of Initiation Complex - causes misreading of mRNA - Bactericidal
Cardiac glycoside (inotropic agent).
- NaHCO3

19. What is the lab value used to monitor the effectiveness of Warfarin therapy?
Bactericidal for: Gram + rod and cocci - Gram - cocci - and Spirochetes
- Quinidine - quinine
The PT.
1. Phospholipase A2 is prevented from releasing arachidonic acid 2. Decreases protein synthesis thus lowering amount of Cyclooxygenase enzymes

20. How is Ribavirin used clinically?
Directly of indirectly aid conversion of plasminogen to plasmin Which cleaves thrombin and fibrin clots. (It is claimed that tPA specifically converts fibrin - bound plasminogen to plasmin.)
Beta - lactamase cleavage of Beta - lactam ring
- Glucocorticoid withdrawal
for RSV

21. What is the mechanism of action and clinical use of the antiandrogen Flutamide?
Flutamide is a nonsteroidal competitive inhibitor of androgens at the testosterone receptor - used in prostate carcinoma.
Irreversibly inhibits H+/K+ ATPase in stomach parietal cells.
Vd= (Amt. of drug in body/ Plasma drug conc.)
Digitoxin>95% Digoxin 75%

22. How is Trimethoprim used clinically?
Cell membrane Ca2+ channels of cardiac sarcomere
- Cloazapine - carbamazapine - colchicine - PTU
- Tamoxifen
Used in combination therapy with SMZ to sequentially block folate synthesis

23. For Heparin What is the Route of administration
proximal convoluted tubule - thin descending limb - and collecting duct
Paranteral (IV - SC)
Antimetabolite derivative of 6- mercaptopurine that interferes with the metablolism and synthesis of nucleic acid.
RESPIre

24. What is the mechanism of Tacrolimus (FK506)?
Chronic anticoagulation.
Similar to cyclosporine; binds to FK- binding protein - inhibiting secretion of IL-2 and other cytokines.
Acute gout.
dizziness - flushing - constipation (verapamil) - nausea

25. Preferential action of the Ca2+ channel blockers at vascular smooth muscle?
- MT polymerization stabilizer - Ovarian & breast CA - Myelosupperession & hypersensitivity.
Constant FRACTION eliminated per unit time.(exponential)
Activates antithrombin III
vascular sm. Mus.: Nifedipine>Diltiazem>Verapamil

26. Name three K+ sparing diuretics?
Spironolactone - Triamterene - Amiloride (the K+ STAys)
Inhibit RT of HIV and prevent the incorporation of viral genome into the host DNA
Does not cross
Blocks Peptide Bond formation at the 50S subunit - Bacteriostatic

27. What is the loading dose formula?
Ld= (CpxVd)/F Cp=plasma conc. F= Bioaval.
hyperaldosteronism - K+ depletion - CHF
When pts have Low CD4+ (< 500 cells/cubic mm) or a High Viral Load
Beta1 more than B2

28. ACE inhibitors - clinical use?
viral kinase
hypertension - CHF - diabetic renal disease
Penicillin - Cephalosporins - Vancomycin - Aminoglycosides - Fluoroquinolones - Metronidazole
Anaerobic infections (e.g. - B. fragilis - C. perfringens)

29. What is Clindamycin used for clinically?
- Cloazapine - carbamazapine - colchicine - PTU
Anaerobic infections (e.g. - B. fragilis - C. perfringens)
- Hypersensitivity reactions - Hemolysis - Nephrotoxicity (tubulointerstitial nephritis) - Kernicterus in infants Displace other drugs from albumin (e.g. - warfarin)
1. Predisposes to viral infections and lymphoma 2. Nephrotoxic (preventable with mannitol diuresis)

30. Ca2+ channel blockers - clinical use?
- Bleomycin - amiodarone - busulfan
Acetylates and irreversibly inhibits cyclooxygenase (COX I and COX II) to prevent the conversion of arachidonic acid to prostaglandins.
It inhibits release of NE.
hypertension - angina - arrhythmias

31. What is the clinical use for Sildenafil (Viagra)?
decrease AP duration - affects ischemic or depolarized Purkinje and ventricular system
Erectile dysfunction.
Inhibits xanthine oxidase - decresing conversion of xanthine to uric acid.
Peptic ulcer disease.

32. What is the category of drug names ending in - tropin (e.g. Somatotropin)
Inhibt Assembly of new virus by Blocking Protease Enzyme
blocks SR Ca2+ channels
Pituitary hormone.
Cell membrane Ca2+ channels of cardiac sarcomere

33. MOA: Block DNA topoisomerases
1. Pioglitazone 2. Rosiglitazone.
Quinolones
They inhibit reuptake of NE at the nerve terminal (as does cocaine).
Mycobacterium tuberculosis - the only agent used as solo prophylaxis against TB

34. What is the MOA of Amantadine?
distal convoluted tubule (early)
Blocks viral penetration/uncoating; may act to buffer the pH of the endosome
Norepinephrine
Cardiac glycoside (inotropic agent).

35. How is Ganciclovir used clinically?
It would increase to ~ 100 beats/min. Both sympathetic and vagal stimulation would be knocked out - but the SA node has an intrinsic pace of 100 beats/min - Which is normally checked by vagal stimulation.
Terminal D- ala of cell wall replaced with D- lac; Decreased affinity
CMV - esp in Immunocompromised patients
ACIDazolamide' causes acidosis

36. Adverse effects of beta - blockers?
Gram + cocci - Gram - rods - and Anerobes
GI discomfort - Acute cholestatic hepatitis - Eosinophilia - Skin rashes
Nonspecific beta - agonist; desired effect is the relaxation of bronchial smooth muscle (Beta 2). Adverse effect is tachycardia (Beta 1).
impotence - asthma - CV effects (bradycardia - CHF - AV block) - CNS effects (sedation - sleep alterations)

37. What is the memory key for the action of Sildenafil (Viagra)?
compensatory tachycardia - fluid retention - lupus - like syndrome
Sildenafil fills the penis
- Tetracycline
Primaquine

38. How would hemicholinium treatment affect cholinergic neurons?
Hydralazine and Minoxidil
Hemicholinium inhibits the transport of choline into the nerve - thus inhibiting formation of ACh.
- Alkalating agents+cisplatin - Doxorubicin+Dactinomycin - Bleomycin - Etoposide
- Class III antiarrhythmics (sotalol) - class IA (quinidine)

39. Secretion of What drug is inhibited by Probenacid used to treat chronic gout?
Beta - lactam antibiotics
Penicillin.
Inhibits xanthine oxidase - decresing conversion of xanthine to uric acid.
Fluconazole - Ketoconazole - Clotrimazole - Miconazole - Itraconazole

40. Which drug(s) cause this reaction: Hepatitis?
Hydralazine and Minoxidil
Inhibits bacterial Dihydrofolate Reductase - Bacteriostatic
Alpha -1 antagonist
- Isoniazid

41. Ca2+ sensitizers'- site of action?
troponin - tropomyosin system
Norepinephrine (Alpha1 -2 and beta 1)
- Steroids - Tamoxifen
Blocks Peptide Bond formation at the 50S subunit - Bacteriostatic

42. Which drug(s) cause this reaction: Cough?
- ACE inhibitors (Losartan>no cough)
Phenothiazine (neuroleptic - antiemetic).
To inhibit renal Dihydropeptidase I and decrease Imipenem inactivation in the renal tubules
Cardiac glycoside (inotropic agent).

43. What is the category of drug names ending in - cillin (e.g. Methicillin)
- Fluoroquinolones
Increased systolic and pulse pressure - decreased diastolic pressure - and little change in mean pressure.
Penicillin.
Methylxanthine.

44. Foscarnet toxicity?
Atropine pts are suffering from Cholinestrase inhibitor poisining (Nerve gas/Organophosphate poisining)
Beta - lactam antibiotics
Beta -2 agonist.
Nephrotoxicity

45. What are three clinical uses of the Leuprolide?
Carbachol - pilocarpine - physostigmine - echothiophate
1. Addison's disease 2. Inflammation 3. Immune suppression 4. Asthma
Protease Inhibitors and Reverse Transcriptase Inhibitors
1. Infertility (pulsatile) 2. Prostate cancer (continuous: use with flutamide) 3. Uterine fibroids

46. Which drug(s) cause this reaction: Fanconi's syndrome?
- Tetracycline
TMP- SMZ (DOC) - aerosolized pentamidine
Pseudomonas species and Gram - rods
effective in torsade de pointes and digoxin toxicity

47. Antiarrhythmic Class III- effects?
GI side effects. (Indomethacin is less toxic - more commonly used.)
Dopamine; causes its release from intact nerve terminals
increase AP duration - increase ERP - increase QT interval - for use When other arrhythmics fail
Misoprostol is a PGE1 analog that increases the production and secretion of the gastic mucous barrier.

48. IV Penicillin
torsade de pointes
Tetracycline - Doxycycline - Demeclocycline - Minocycline
It affects beta receptors equally and is used in AV heart block (rare).
Penicillin - G

49. Furosemide - clinical use?
As PABA antimetabolites that inhibit Dihydropteroate Synthase - Bacteriostatic
Short.
Finasteride inhibits 5 Alpha - reductase - this decreases the conversion of testosterone to dihydrotestosterone - useful in BPH
edematous states (CHF - cirrhosis - nephrotic syndrome - pulm edema) - HTN - hypercalcemia

50. What parasitic condition is treated with Ivermectin?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183