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. How are Interferons (INF) used clinically?

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

2. What musculo - skeletal side effects in Adults are associated with Floroquinolones?
- Penicillin
Pentamidine
Parkinson patients benefit from antimuscarinic agents through its inhibitory action within the indirect pathway.
Tendonitis and Tendon rupture

3. What are Fluoroquinolones indicated for? (3)
CMV Retinitis in IC pts When Ganciclovir fails
1.Gram - rods of the Urinary and GI tracts (including Pseudomonas) 2.Neisseria 3. Some Gram + organisms
narcolepsy - obesity - and attention deficit disorder (I wouldn't recommend this)
WEPT: Warfarin affects the Extrinsic pathway and prolongs the PT.

4. Which drug(s) cause this reaction: Pseudomembranous colitis?
CL= (rate of elimination of drug/ Plasma drug conc.)
- Clindamycin
Inhibition of 50S peptidyl transferase - Bacteriostatic
Chloramphenicol - Erythromycin/macrolides - Lincomycin - Clindamycin - Streptogramins (quinupristin - dalfopristin)

5. What is the lab value used to monitor the effectiveness of Warfarin therapy?
Theoretically it could be used to block the cephalic phase of acid secretion (vagal stimulation).
- Tamoxifen
fetal renal toxicity - hyperkalemia - Cough - Angioedema - Proteinuria - Taste changes - hypOtension - Pregnancy problems - Rash - Increased renin - Lower Angiotensin II (CAPTOPRIL)
The PT.

6. What is Fluconazole specifically used for?
Praziquantel
Selectively inhibit cyclooxygenase (COX) isoform 2 - Which is found in inflammatory cells nad mediates inflammation and pain; spares COX-1 Which helps maintain the gastric mucosa.
anticholinesterase glaucoma
Cryptococcal meningitis in AIDS patients and Candidal infections of all types

7. Aztreonam ________ to penicillinase
is resistant
Altered bacterial Dihydropteroate Synthetase - Decreased uptake - or Increased PABA synthesis
In 4 half - lifes= (94%) T1/2 = (0.7x Vd)/CL
check PFTs - LFTs - and TFTs

8. What is a common side effect of Colchicine used to treat acute gout - especially When given orally?
GI side effects. (Indomethacin is less toxic - more commonly used.)
toxic
NO AP duration effect. useful in V- tach that progresses to V- fib and in intractable SVT Last RESORT
Ciprofloxacin - Norfloxacin - Ofloxacin - Grepafloxacin - Enoxacin - Nalidixic acid

9. Why would you give a drug like pancuronium or succinylcholine?
Binds to cyclophilins (peptidyl proline cis - trans isomerase) - blocking the differentiation and activation of T cells mainly by inhibiting the production of IL-2 and its receptor.
decrease the slope of phase 4 - increase PR interval (the AV node is particularly sensitive)
Useful in muscle paralysis during surgery or mechanical ventilation.
Reserpine inhibits dopamine transport into vesicles - attenuating its conversion to NE by dopamine beta - hydroxylase.

10. List the specific antidote for this toxin: Opioids
Chronic gout.
Cilastatin
- Cloazapine - carbamazapine - colchicine - PTU
- B51Naloxone / naltrexone (Narcan)

11. Which drug(s) cause this reaction: Stevens - Johnson syn. (3)?
edematous states (CHF - cirrhosis - nephrotic syndrome - pulm edema) - HTN - hypercalcemia
check PFTs - LFTs - and TFTs
- Ethosuxamide - sulfonamides - lamotrigine
Methylzanthine; desired effect is bronchodilation - may cause bronchodilation by inhibiting phosphodiesterase - enzyme involved in degrading cAMP (controversial).

12. What is the MOA for the Macrolides?
torsade de pointes
Minor hepatotoxicity - Drug interactions (activates P450)
Blocks translocation - binds to the 23S rRNA of the 50S subunit - Bacteriostatic
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia

13. What are the four conditions in Which Omeprazole - Lansoprazole is used?
1. Peptic ulcer 2. Gastritis 3. Esophageal reflux 4. Zollinger - Ellison syndrome
Glycoproteins from leukocytes that block various stages of viral RNA and DNA synthesis
- Quinidine - quinine
Inhibt Assembly of new virus by Blocking Protease Enzyme

14. Which drug(s) cause this reaction: P450 induction(6)?
Chronic gout.
- Barbiturates - phenytoin - carbamazipine - rifampin - griseofulvin - quinidine
Hexamethonium is a nicotinic antagonist - and thus is a ganglionic blocker.
Blocks viral penetration/uncoating; may act to buffer the pH of the endosome

15. What are the indications for using amphetamine?

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

16. Reserpine will block the syntheis of this drug and but not its precursor.
- ACE inhibitors (Losartan>no cough)
Blocks Norepi - but not Dopamine
Beta Blockers
Keratin containing tissues - e.g. - nails

17. Name four HMG- CoA reductase inhibitors.
Lovastatin - Pravastatin - Simvastatin - Atorvastatin
Increases coumadin metabolism
Ciprofloxacin - Norfloxacin - Ofloxacin - Grepafloxacin - Enoxacin - Nalidixic acid
Acute gout.

18. What is the effect of TCA's on the adrenergic nerve?
They inhibit reuptake of NE at the nerve terminal (as does cocaine).
Bactericidal for: Gram + rod and cocci - Gram - cocci - and Spirochetes
first dose orthostatic hypotension - dizziness - headache
Inhalational general anesthetic.

19. Which drug increases Sys BP w/o affecting Pulse Pressure
- polymyxins
Meningitis (H. influenza - N. meningitidis - S. pneumoniae) - Conserative treatment due to toxicities
Epinephrine
1. Significant: nephrotoxicity 2. Peripheral neuropathy 3. Hypertension 4. Pleural effusion 5. Hyperglycemia.

20. What should not be taken with Tetracyclines? / Why?
hypertension - angina - arrhythmias
Milk or Antacids - because divalent cations inhibit Tetracycline absorption in the gut
Rheumatoid and osteoarthritis.
new arrhythmias - hypotension

21. For Warfarin What is the Ability to inhibit coagulation in vitro
No
acts at the proximal convoluted tubule to inhibit carbonic anhydrase. Causes self - limited sodium bicarb diuresis and reduction of total body bicarb stores.
ARF - shock - drug overdose - decrease intracranial/intraocular pressure
Antileukotriene; blocks leukotriene receptors.

22. How is Chloramphenical used clinically?
AmOxicillin has greater Oral bioavailability
Warfarin interferes with the normal synthesis and gamma - carboxylation of vitamin K- dependent clotting factors II - VII - IX - and X - Protein C and S via vitamin K antagonism.
Meningitis (H. influenza - N. meningitidis - S. pneumoniae) - Conserative treatment due to toxicities
Beta - lactam antibiotics

23. In What population does Gray Baby Syndrome occur? Why?
Premature infants - because they lack UDP- glucuronyl transferase
IV vitamin K and fresh frozen plasma
- Niacin - Ca++ channel blockers - adenosine - vancomycin
Acetylcholinesterase; ACh is broken down into choline and acetate.

24. List the specific antidote for this toxin: TPA & Streptokinase
Heparin catalyzes the activation of antithrombin III.
They inhibit reuptake of NE at the nerve terminal (as does cocaine).
- Aminocaproic acid
1. Predisposes to viral infections and lymphoma 2. Nephrotoxic (preventable with mannitol diuresis)

25. What is the mechanism of action of Omeprazole - Lansoprazole?
hypokalemia - slight hyperlipidemia - hyperuricemia - lassitude - hypercalcemia - hyperglycemia
They inhibit reuptake of NE at the nerve terminal (as does cocaine).
Irreversibly inhibits H+/K+ ATPase in stomach parietal cells.
Gram + and Anerobes

26. What drug is used to treat Trematode/fluke (e.g. - Schistosomes - Paragonimus - Clonorchis) or Cysticercosis
Irreversibly inhibits H+/K+ ATPase in stomach parietal cells.
Hypersensitivity reactions
Praziquantel
GnRH analog with agonist properties When used in pulsatile fashion and antagonist properties When used in continuous fashion - causing a transient initial burst of LH and FSH

27. List the mechanism - clinical use - & toxicity of 5 FU.
reversible SLE- like syndrome
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression
Close K+ channels in Beta - cell membrane leading to cell depolarization causing insulin release triggered by increase in Calcium ion influx.
hypokalemia - slight hyperlipidemia - hyperuricemia - lassitude - hypercalcemia - hyperglycemia

28. What are the products and their toxicities of the metabolism of Methanol by / alcohol dehydrogenase?
- Formaldehyde & formic acid - severe acidosis & retinal damage
Hemolytic anemia
It acts presynaptically to increase NE release.
Inhibits IMP Dehydrogenase (competitively) - and therefore blocks Guanine Nucleotide synthesis

29. K+ sparing diuretics - site of action?
Parkinson patients benefit from antimuscarinic agents through its inhibitory action within the indirect pathway.
cortical collecting tubule
Vibrio cholerae Acne Chlamydia Ureaplasma Urealyticum Mycoplasma pneumoniae Borrelia burgdorferi (Lyme's) Rickettsia Tularemia
Digitoxin>95% Digoxin 75%

30. What is the chemical name for Ganciclovir?
Blocks translocation - binds to the 23S rRNA of the 50S subunit - Bacteriostatic
- Flumazenil
DHPG (dihydroxy-2- propoxymethyl guanine)
Quinidine - Amiodarone - Procainamide - Disopyramide

31. Adverse effects of Captopril?
fetal renal toxicity - hyperkalemia - Cough - Angioedema - Proteinuria - Taste changes - hypOtension - Pregnancy problems - Rash - Increased renin - Lower Angiotensin II (CAPTOPRIL)
prevention of nodal arrhythmias (SVT)
is resistant
CL= (rate of elimination of drug/ Plasma drug conc.)

32. 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.
Praziquantel
When pts have Low CD4+ (< 500 cells/cubic mm) or a High Viral Load
- Weak Acids>Alkinalize urine(CO3) to remove more - Weak bases>acidify urine to remove more

33. Where does Griseofulvin deposit?
1. Significant: nephrotoxicity 2. Peripheral neuropathy 3. Hypertension 4. Pleural effusion 5. Hyperglycemia.
osmotic diuretic - increase tubular fluid osmolarity - thereby increasing urine flow
Inhibits Viral DNA polymerase
Keratin containing tissues - e.g. - nails

34. How does angiotensin II affect NE release?
Ipratropium
It acts presynaptically to increase NE release.
anticholinesterase glaucoma
orthostatic and exercise hypotension - sexual dysfunction - diarrhea

35. What are Polymyxins used for?
Ipratropium
Resistant Gram - infections
Aminoglycosides
Epinephrine to treat anaphylaxis. Also useful if you have open angle glaucoma - asthma - or hypotension.

36. What is the clinical use for Sucralfate?
Inhibits IMP Dehydrogenase (competitively) - and therefore blocks Guanine Nucleotide synthesis
Peptic ulcer disease.
Choline acetyltransferase
Botulinum

37. Common side effects associated with Clindamycin include?
Sotalol - Ibutilide - Bretylium - Amiodarone
- Shifts the curve down - reduces Vmax
Pseudomembranous colitis (C. difficile) - fever - diarrhea
Fast vs. Slow Acetylators

38. Adverse effects of Losartan?
GnRH analog with agonist properties When used in pulsatile fashion and antagonist properties When used in continuous fashion - causing a transient initial burst of LH and FSH
fetal renal toxicity - hyperkalemia
Epinephirine(Alpha1 -2 and Beta 1 -2)
1. Weight gain 2. Hepatotoxicity (troglitazone)

39. What is the clinical use for Ampicillin and Amoxicillin?
Extended spectrum penicillin: certain Gram + bacteria and Gram - rods
Severe Gram - rod infections.
1. Bleeding 2. Thrombocytopenia 3. Drug - drug interactions
collecting ducts

40. Your patient wants an effective drug to treat his motion sickness - What would you prescribe
Scopolamine
Protamine Sulfate is used for rapid reversal of heparinization (positively charged molecule that binds to negatively charged heparin).
Erythromycin - Azithromycin - Clarithromycin
Hypersensitivity reactions

41. Mannitol - mechanism?
anticholinesterase glaucoma
- Phase I (clinical tests) - Phase II - Phase III - PhaseIV (surveillance)
osmotic diuretic - increase tubular fluid osmolarity - thereby increasing urine flow
Resistant Gram - infections

42. What effect would atropine have on a patient with peptic ulcer disease?
Chagas' disease - American Trypanosomiasis (Trypanosoma cruzi)
Inhibits cell wall mucopeptide formation - Bactericidal
Theoretically it could be used to block the cephalic phase of acid secretion (vagal stimulation).
- Shifts the curve down - reduces Vmax

43. What is the MOA of the RT Inhibitors?
Chagas' disease - American Trypanosomiasis (Trypanosoma cruzi)
Misoprostol is a PGE1 analog that increases the production and secretion of the gastic mucous barrier.
dry mouth - sedation - severe rebound hypertension
Inhibit RT of HIV and prevent the incorporation of viral genome into the host DNA

44. What enzyme is responsible for the degredation of Ach
Blocks Peptide Bond formation at the 50S subunit - Bacteriostatic
GI distress - Tooth discoloration and Inhibition of bone growth in children - Fanconi's syndrome - Photosensitivity
Acetylcholine esterase
Binds to cyclophilins (peptidyl proline cis - trans isomerase) - blocking the differentiation and activation of T cells mainly by inhibiting the production of IL-2 and its receptor.

45. What is the MOA for Carbenicillin - Piperacillin - and Ticarcillin?
Same as penicillin. Extended spectrum antibiotics
Primaquine
Gram - rods: Klebsiella species - Pseudomonas species - Serratia species
Glycoproteins from leukocytes that block various stages of viral RNA and DNA synthesis

46. What is the mechanism of action of Ticlopidine - Clopidogrel
1. Gastric ulceration 2. Bleeding 3. Hyperventilation 4. Reye's syndrome 5. Tinnitus (CN VIII)
Chronic gout.
Beta antagonist.
Inhibits platelet aggregation by irreversibly inhibiting the ADP pathway involved in the binding of fibrinogen.

47. Mannitol - site of action?
Increases mean - systolic - and diastolic bp - while there is little change in pulse pressure.
Increases coumadin metabolism
proximal convoluted tubule - thin descending limb - and collecting duct
Zidovudine (AZT) - Didanosine (ddI) - Zalcitabine (ddC) - Stavudine (d4T) - Lamivudine (3TC)

48. What is the only depolarizing neuromuscular blocking agent?
Succinylcholine
Same as penicillin. Extended spectrum antibiotics
troponin - tropomyosin system
- DNA intercalator - Hodgkin's - myeloma - sarcoma - and solid tumors - Cardiotoxicity & alopecia

49. What is an additional side effect of Methicillin?
torsade de pointes
Interstitial nephritis
Misoprostol is a PGE1 analog that increases the production and secretion of the gastic mucous barrier.
It must be Phosphorylated by Viral Thymidine Kinase

50. What is the memory key for Isoniazid (INH) toxicity?
INH: Injures Neurons and Hepatocytes
Scopolamine
Rare.
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.