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 four unwanted effects of Clomiphene use?
Triple sulfas or SMZ
Reserpine inhibits dopamine transport into vesicles - attenuating its conversion to NE by dopamine beta - hydroxylase.
1. Hot flashes 2. Ovarian enlargement 3. Multiple simultaneous pregnancies 4. Visual disturbances
Rare.

2. What is a sign of toxicity with the use of thrombolytics?
Bleeding.
Giant Roundworm (Ascaris) - Hookworm (Necator/Ancylostoma) - Pinworm (Enterobius)
No
- Haloperidol - chlorpromazine - reserpine - MPTP

3. Decrease Digitoxin dose in renal failure?
Decreases synthesis of Mycolic Acid
The COX-2 inhibitors should not have the corrosive effects of other NSAIDs on the gastrointestinal lining.
Oral treatment of superficial infections
NO

4. What are the products and their toxicities of the metabolism of Ethylene Glycol by / alcohol dehydrogenase?
proximal convoluted tubule
- Oxalic acid - Acidosis & nephrotoxicity
Decreased uptake or Increased transport out of cell
Short.

5. Digoxin v. Digitoxin: excretion?
Digoxin=urinary Digitoxin=biliary
Penicillin - G
- Glucocorticoid withdrawal
Inhibits cell wall mucopeptide formation - Bactericidal

6. What is the clinical use for Clomiphene?
Inhibit viral DNA polymerase
decrease myocardial O2 consumption by: 1- decreasing end diastolic volume 2- decreasing BP 3- decreasing HR 4- decreasing contractility 5- decreasing ejection time
Chronic gout.
Treatment of infertility.

7. IV Penicillin
Penicillin - G
Bacitracin - Vancomycin
Foscarnet = pyroFosphate analog
- EDTA - dimercaprol - succimer - & penicillamine

8. Can Warfarin be used during pregnancy?
Terminal D- ala of cell wall replaced with D- lac; Decreased affinity
compensatory tachycardia - fluid retention - lupus - like syndrome
No
No - warfarin - unlike heparin - can cross the placenta.

9. How does botulinum toxin result in respiratory arrest?
Neutropenia
Prevents the release of ACh - Which results in muscle paralysis.
Aminoglycosides
Spironolactone - Triamterene - Amiloride (the K+ STAys)

10. What are the clinical indications for Azole therapy?
troponin - tropomyosin system
1. Antipyretic 2. Analgesic 3. Anti - inflammatory 4. Antiplatelet drug.
Leukotrienes increasing bronchial tone.
Systemic mycoses

11. What is the chemical name for Ganciclovir?
1. Reliable (<1% failure) 2. Lowers risk of endometrial and ovarian cancer 3. Decreased incidence of ectopic pregnancy 4. Lower risk of pelvic infections 5. Regulation of menses
DHPG (dihydroxy-2- propoxymethyl guanine)
- Hydralazine - Procainamide - INH - phenytoin
Increase target cell response to insulin.

12. Name common Polymyxins
Acute (hours)
Delirium - Tremor - Nephrotoxicity
Acetaminophen has antipyretic and analgesic properties - but lacks anti - inflammatory properties.
Polymyxin B - Polymyxin E

13. Which drug(s) cause this reaction: Disulfram - like reaction (4) ?
Glycoproteins from leukocytes that block various stages of viral RNA and DNA synthesis
- Metronidazole - certain cephalosporins - procarbazine - sulfonylureas
Triple sulfas or SMZ
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.)

14. Toxicities associated with Acyclovir?
Local anesthetic.
Inhibit steroid synthesis - used in the treatment of polycystic ovarian syndrome to prevent hirsutism.
Delirium - Tremor - Nephrotoxicity
Beta 2 agonist; desired effect is the relaxation of bronchial smooth muscle (Beta 2). Use during acute exacerbation.

15. What reversal agent could a Anes give to reverse the effects of Atropine
Inhibit intestinal bursh border Alpha - glucosidases; delayed hydrolysis of sugars and absorption of sugars leading to decresed postprandial hyperglycemia.
1) Chloramphenical = bacteriostatic 2) Erythromycin = bacteriostatic 3) Lincomycin = bacteriostatic 4)cLindamycin = bacteriostatic
Bethanechol - Neostigmine - physostigmine
- Halothane - Valproic acid - acetaminophen - Amantia phalloides

16. What are three clinical uses of the Leuprolide?
Hemolysis (if G6PD deficient) - Neurotoxicity - Hepatotoxicity - SLE- like syndrome
Chronic anticoagulation.
1. Infertility (pulsatile) 2. Prostate cancer (continuous: use with flutamide) 3. Uterine fibroids
TCA

17. Are penicillinase resistant
Saquinavir - Ritonavir - Indinavir - Nelfinavir
Methicillin - Nafcillin - and Dicloxacillin
Initially vasoconstriction would increase bp - but then it acts on central alpha -2 receptors to decrease adrenergic outflow resulting in decreased bp.
1. Hydrocortisone 2. Predisone 3. Triamcinolone 4. Dexamethasone 5. Beclomethasone

18. Antiarrhythmic class II- effects?
Choline acetyltransferase
1. Peptic ulcer 2. Gastritis 3. Esophageal reflux 4. Zollinger - Ellison syndrome
decrease the slope of phase 4 - increase PR interval (the AV node is particularly sensitive)
1. Gastric ulceration 2. Bleeding 3. Hyperventilation 4. Reye's syndrome 5. Tinnitus (CN VIII)

19. List the specific antidote for this toxin: Arsenic (all heavy metals)
No
- Dimercaprol - succimer
Aminoglycosides - Tetracyclines
Beta adrenergic receptors and Ca2+ channels (stimulatory)

20. Can Heparin be used during pregnancy?
Inhibits bacterial Dihydrofolate Reductase - Bacteriostatic
Reserpine inhibits dopamine transport into vesicles - attenuating its conversion to NE by dopamine beta - hydroxylase.
Mg = Must go to the bathroom.
Yes - it does not cross the placenta.

21. Preferential action of the Ca2+ channel blockers at vascular smooth muscle?
vascular sm. Mus.: Nifedipine>Diltiazem>Verapamil
Bismuth and Amoxicillin or Tetracycline; against Helobacter pylori
Dobutamine has more of an affintiy for beta -1 than beta -2 - and is used for treating heart failure and shock. Albuterol and terbutaline is the reverse - and is used in treatment of acute asthma.
- Clindamycin

22. Adenosine - clinical use?
DOC in diagnosing and abolishing AV nodal arrhythmias
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.
Nitrates
1. Tolbutamide 2. Chlorpropamide 3. Glyburide 4. Glipizide

23. What conditions are treated with Metronidazole?
Cephalosporins
Tetracycline - Doxycycline - Demeclocycline - Minocycline
Headache - flushing - dyspepsia - blue - green color vision.
Giardiasis - Amoebic dysentery (E. histolytica) - Bacterial vaginitis (Gardnerella vaginalis) - Trichomonas

24. What is the memory key for Metronidazole's clinical uses?
Enterobacter
GET on the Metro
Dopamine; causes its release from intact nerve terminals
edrophonium (extremely short acting anticholinesterase)

25. What are common toxic side effects of Sulfonamides? (5)
- Hypersensitivity reactions - Hemolysis - Nephrotoxicity (tubulointerstitial nephritis) - Kernicterus in infants Displace other drugs from albumin (e.g. - warfarin)
Pentamidine
Imipenem
Penicillin - G

26. Do Tetracyclines penetrate the CNS?
Chronic gout.
1. Weight gain 2. Hepatotoxicity (troglitazone)
Only in limited amounts
Leukotrienes increasing bronchial tone.

27. Resistance mechanisms for Tetracycline
Decreased uptake or Increased transport out of cell
Increased systolic and pulse pressure - decreased diastolic pressure - and little change in mean pressure.
distal convoluted tubule (early)
depresses ectopic pacemakers - especially in digoxin toxicity

28. Spironolactone - mechanism?
Inhibits cell wall synthesis ( binds to PBP3). A monobactam
Same as penicillin. Extended spectrum antibiotics
AV nodal cells
competitive inhibirot of aldosterone in the cortical collecting tubule

29. For Heparin What is the Treatment for overdose
DHPG (dihydroxy-2- propoxymethyl guanine)
Protamine sulfate
osmotic diuretic - increase tubular fluid osmolarity - thereby increasing urine flow
orthostatic and exercise hypotension - sexual dysfunction - diarrhea

30. 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.
Intrathecally
Rifampin - Ethambutol - Streptomycin - Pyrazinamide - Isoniazid (INH)
Tendonitis and Tendon rupture

31. Acetaminophen has What two clinical uses and lacks What one clinical use of the NSAIDs?
- Alkalating agents+cisplatin - Doxorubicin+Dactinomycin - Bleomycin - Etoposide
Acetaminophen has antipyretic and analgesic properties - but lacks anti - inflammatory properties.
Inhibits platelet aggregation by irreversibly inhibiting the ADP pathway involved in the binding of fibrinogen.
dry mouth - sedation - severe rebound hypertension

32. Which drug(s) cause this reaction: G6PD hemolysis(8)?
- Sulfonamides - INH - ASA - Ibuprofen - primaquine - nitrofurantoin /- pyrimethamine - chloramphenicol
orthostatic and exercise hypotension - sexual dysfunction - diarrhea
It affects beta receptors equally and is used in AV heart block (rare).
Digitoxin 168hrs Digoxin 40 hrs

33. What is the clinical use of Tacrolimus (FK506)?
Hypersensitivity reactions
cortical collecting tubule
increase AP duration - increase ERP - increase QT interval - for use When other arrhythmics fail
Potent immunosuppressive used in organ transplant recipients.

34. What is the category - desired effect - and possible mechanism of Theophylline in treating Asthma?
Methylzanthine; desired effect is bronchodilation - may cause bronchodilation by inhibiting phosphodiesterase - enzyme involved in degrading cAMP (controversial).
osmotic diuretic - increase tubular fluid osmolarity - thereby increasing urine flow
Triple Therapy' 2 Nucleoside RT Inhibitors with a Protease Inhibitor
Increases mean - systolic - and diastolic bp - while there is little change in pulse pressure.

35. Explain potency in relation to full and partial agonists(2).
Amphotericin B - Nystatin - Fluconazole/azoles
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia
- Constant AMOUNT eliminated per unit time. - Etoh & ASA
- partial agonist can have increased - decreased - /A21or equal potency as full agonist. - Potency is an independent factor.

36. What is a common side effect of Colchicine used to treat acute gout - especially When given orally?
Acetylates and irreversibly inhibits cyclooxygenase (COX I and COX II) to prevent the conversion of arachidonic acid to prostaglandins.
To inhibit renal Dihydropeptidase I and decrease Imipenem inactivation in the renal tubules
Cestode/tapeworm (e.g. - D. latum - Taenia species Except Cysticercosis
GI side effects. (Indomethacin is less toxic - more commonly used.)

37. What are Methicillin - Nafcillin - and Dicloxacillin used for clinically?
Immediate anticoagulation for PE - stroke - angina - MI - DVT.
Chronic anticoagulation.
Staphlococcus aureus
Cell membrane Ca2+ channels of cardiac sarcomere

38. How can the toxic effects of TMP be ameliorated?
With supplemental Folic Acid
Albuterol - tertbutaline
Rash - Pseudomembranous colitis
Terminal D- ala of cell wall replaced with D- lac; Decreased affinity

39. Why are Methicillin - Nafcillin - and Dicloxacillin penicillinase resistant?
Due to the presence of a bulkier R group
Megaloblastic anemia - Leukopenia - Granulocytopenia
Chronic (weeks or months)
Topical and Oral - for Oral Candidiasis (Thrush)

40. What is the memory key involving the '4 R's of Rifampin?'
Impairs the synthesis of vitamin K- dependent clotting factors
1. RNA pol inhibitor 2. Revs up P450 3. Red/orange body fluids 4. Rapid resistance if used alone
- Physostigmine salicylate
No - it inhibits the release of Nor Epi

41. Digitalis - site of action?
Na/K ATPase
constipation - flushing - edema - CV effects (CHF - AV block - sinus node depression) - and torsade de pointes (Bepridil)
Inhibit Ergosterol synthesis
Vibrio cholerae Acne Chlamydia Ureaplasma Urealyticum Mycoplasma pneumoniae Borrelia burgdorferi (Lyme's) Rickettsia Tularemia

42. What do you treat Nematode/roundworm (pinworm - whipworm) infections with?
Dopamine; causes its release from intact nerve terminals
Acetylcholinesterase; ACh is broken down into choline and acetate.
Mebendazole/Thiabendazole - Pyrantel Pamoate
As PABA antimetabolites that inhibit Dihydropteroate Synthase - Bacteriostatic

43. Name the common Non - Nucleoside Reverse Transcriptase Inhibitors
Does not cross
Nevirapine - Delavirdine
Erythromycin - Azithromycin - Clarithromycin
- Chloramphenicol - benzene - NSAIDS - PTU - phenytoin

44. What is clinical use for Carbenicillin - Piperacillin - and Ticarcillin?
1. Renal damage 2. Aplastic anemia 3. GI distress
Pseudomonas species and Gram - rods
all except the K+ sparing diuretics Spironolactone - Triamterene - Amiloride
Rifampin (DOC) - minocycline

45. Which drug(s) cause this reaction: Oto and Nephrotoxicity (3)?
- Shifts the curve down - reduces Vmax
DOC in diagnosing and abolishing AV nodal arrhythmias
Pralidoxime regenerates active cholinesterase.
- aminoglycosides - loop diuretics - cisplatin

46. What is a Ribavirin toxicity?
- S- phase anti - metabolite folate analogue - Luk - Lymp - sarc - RA - & psoriasis / - Reversible myelosuppression
Cestode/tapeworm (e.g. - D. latum - Taenia species Except Cysticercosis
Hemolytic anemia
- Quinidine - quinine

47. What is the category of drug names ending in - navir (e.g. Saquinavir)
Protease inhibitor.
Misoprostol is a PGE1 analog that increases the production and secretion of the gastic mucous barrier.
Constant FRACTION eliminated per unit time.(exponential)
1. Addison's disease 2. Inflammation 3. Immune suppression 4. Asthma

48. What is the category of drug names ending in - caine (e.g. Lidocaine)
Inhibits CMV DNA polymerase
Binds Ergosterol - forms Membrane Pores that Disrupt Homeostatis
Local anesthetic.
Penicillin - Cephalosporins - Vancomycin - Aminoglycosides - Fluoroquinolones - Metronidazole

49. What drug is used to diagnose myasthenia gravis?
edrophonium (extremely short acting anticholinesterase)
Pseudomonas species and Gram - rods
Vd= (Amt. of drug in body/ Plasma drug conc.)
Hypersensitivity reactions

50. What is the mechanism of action of the Alpha - glucosidase inhibitors?
- Sulfonamides - INH - ASA - Ibuprofen - primaquine - nitrofurantoin /- pyrimethamine - chloramphenicol
Inhibit intestinal bursh border Alpha - glucosidases; delayed hydrolysis of sugars and absorption of sugars leading to decresed postprandial hyperglycemia.
Ceftriaxone
Hypersensitivity reactions