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. Adenosine - clinical use?
thiazides - amiloride
DOC in diagnosing and abolishing AV nodal arrhythmias
diuretics - sympathoplegics - vasodilators - ACE inhibitors - Angiotensin II receptor inhibitors
AZT

2. IV Penicillin
Penicillin - G
- Steroids - Tamoxifen
Ca2+ (Loops Lose calcium)
Inhibits cell wall mucopeptide formation - Bactericidal

3. Thiazides - site of action?
increased AP duration - increased ERP increased QT interval. Atrial and ventricular.
distal convoluted tubule (early)
As an anticholinesterase it increases endogenous ACh and thus increases strength.
cholestyramine - colestipol

4. What are the clinical uses for 1st Generation Cephalosporins?
Gram + cocci - Proteus mirabilis - E. coli - Klebsiella pneumoniae (PEcK)
Inhibits xanthine oxidase - decresing conversion of xanthine to uric acid.
Penicillin - Ampicillin - Ticarcillin - Pipercillin - Imipenem - Aztreonam - Cephalosporins
Phase 1 = prolonged depolarization - no antidote - effect potentiated by anticholinesterase; Phase 2 = repolarized but blocked - an anticholinesterase is the antidote for this phase.

5. Which drug(s) cause this reaction: Pseudomembranous colitis?
- NaHCO3
Antiprotozoal: Giardia - Entamoeba - Trichomonas - Gardnerella vaginalis Anaerobes: Bacteroides - Clostridium
- Clindamycin
As an anticholinesterase it increases endogenous ACh and thus increases strength.

6. How is Foscarnet used clinically?
- Acetaldehyde - Nausea - vomiting - headache - & hypotension
CMV Retinitis in IC pts When Ganciclovir fails
Minor hepatotoxicity - Drug interactions (activates P450)
Pralidoxime regenerates active cholinesterase.

7. How is Amantadine used clinically?

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

8. What is Ketoconazole specifically used for?
GI side effects. (Indomethacin is less toxic - more commonly used.)
cinchonism: HA - tinnitus - thrombocytopenia - torsade de pointes due to increased QT interval
Blastomyces - Coccidioides - Histoplasma - C. albicans; Hypercortisolism
Phosphorylation by a Viral Kinase

9. Ca2+ sensitizers'- site of action?
1. Heavy bleeding 2. GI effects (n/v - anorexia) 3. Abdominal pain
check PFTs - LFTs - and TFTs
troponin - tropomyosin system
Binding to the presynaptic alpha 2 release modulating receptors

10. List the specific antidote for this toxin: TPA & Streptokinase
Imipenem
- Aminocaproic acid
YES
Inhibits Viral DNA polymerase

11. Which diuretics decrease urine Ca2+?
Acetaminophen has antipyretic and analgesic properties - but lacks anti - inflammatory properties.
Inhibits cell wall synthesis ( binds to PBP3). A monobactam
Norepinephrine
thiazides - amiloride

12. Cocaine shares is mechanism of action with What antidepressant
TCA
increase AP duration - increase ERP - increase QT interval - for use When other arrhythmics fail
NE increases bp - Which stimulates baroreceptors in the carotid sinus and the aorta. The CNS signals through vagal stimulation to decrease heart rate.
decrease

13. What is the main clinical use for the thrombolytics?
Interferes with microtubule function - disrupts mitosis - inhibits growth
- Tricyclic antidepressants
Acute (hours)
Early myocardial infarction.

14. Name two classes of drugs for HIV therapy
Protease Inhibitors and Reverse Transcriptase Inhibitors
The PTT.
Erythromycin - Azithromycin - Clarithromycin
Albuterol - tertbutaline

15. Does Heparin have a long - medium - or short half life?
Rash - Pseudomembranous colitis
Hormone synthesis inhibition (Gynecomastia) - Liver dysfunction (Inhibits CYP450) - Fever - Chills
Activates antithrombin III
Short.

16. Name the common Nucleoside Reverse Transcriptase Inhibitors
NO AP duration effect. useful in V- tach that progresses to V- fib and in intractable SVT Last RESORT
Zidovudine (AZT) - Didanosine (ddI) - Zalcitabine (ddC) - Stavudine (d4T) - Lamivudine (3TC)
NO HYPERURICEMIA - NO SULFA AllERGY; same as furosemide otherwise
Carbachol - pilocarpine - physostigmine - echothiophate

17. Name the steps in drug approval(4)?
Decreases synthesis of Mycolic Acid
Altered bacterial Dihydropteroate Synthetase - Decreased uptake - or Increased PABA synthesis
all except the K+ sparing diuretics Spironolactone - Triamterene - Amiloride
- Phase I (clinical tests) - Phase II - Phase III - PhaseIV (surveillance)

18. Which drug(s) cause this reaction: Thrombotic complications?
Beta -2 agonist.
Acetaminophen has antipyretic and analgesic properties - but lacks anti - inflammatory properties.
- Oral Contraceptives
Because they require some residual islet function.

19. Preferential action of the Ca2+ channel blockers at vascular smooth muscle?
vascular sm. Mus.: Nifedipine>Diltiazem>Verapamil
- partial agonist can have increased - decreased - /A21or equal potency as full agonist. - Potency is an independent factor.
Methylation of rRNA near Erythromycin's ribosome binding site
Acute coronary syndrome; coronary stenting. Decreases the incidence or recurrence of thrombotic stroke.

20. How does a noncompetitive antagonist effect an agonist?
Terminal D- ala of cell wall replaced with D- lac; Decreased affinity
Penicillin - V
These B-2 agonists cause respiratory smooth muscle to relax.
- Shifts the curve down - reduces Vmax

21. What is the clinical use for Nystatin?
Yes - it does not cross the placenta.
Neutropenia
Clomiphene is a partial agonist at estrogen receptors in the pituitary gland. Prevents normal feedback inhibition and increses release of LH and FSHfrom the pituitary - Which stimulates ovulation.
Topical and Oral - for Oral Candidiasis (Thrush)

22. What is the category and mechanism of action of Zileuton in Asthma treatment?
Fever/Chills - Hypotension - Nephrotoxicity - Arrhythmias
K+ wasting - metabolic alkalosis - hypotension - ototoxicity
1. Weight gain 2. Hepatotoxicity (troglitazone)
Antileukotriene; blocks synthesis by lipoxygenase.

23. Steady state concentration is reached in __ number of half - lifes
- Dimercaprol - succimer
Babiturate.
post MI and digitalis induced arrhythmias
In 4 half - lifes= (94%) T1/2 = (0.7x Vd)/CL

24. Name three K+ sparing diuretics?
The PTT.
Because they require some residual islet function.
Spironolactone - Triamterene - Amiloride (the K+ STAys)
Increases mean - systolic - and diastolic bp - while there is little change in pulse pressure.

25. What is the category of drug names ending in - cillin (e.g. Methicillin)
Fast vs. Slow Acetylators
- Antipsychotics
Penicillin.
1. Taken daily 2. No protection against STDs 3. Raises triglycerides 4. Depression - weight gain - nausea - HTN 5. Hypercoagulable state

26. Which drug(s) cause this reaction: P450 inhibition(6)?
- S- phase anti - metabolite folate analogue - Luk - Lymp - sarc - RA - & psoriasis / - Reversible myelosuppression
Nephrotoxicity (esp. with Cephalosporins) - Ototoxicity (esp. with Loop Diuretics)
- Cimetidine - ketoconazole - grapefruit juice - erythromycin - INH - sulfonamides
hypertension - angina - arrhythmias

27. How would you treat African Trypanosomiasis (sleeping sickness)?
impotence - exacerbation of asthma - CV effects - CNS effects - may mask hypoclycemia
Gemfibrozil - Clofibrate
Suramin
Zidovudine (AZT) - Didanosine (ddI) - Zalcitabine (ddC) - Stavudine (d4T) - Lamivudine (3TC)

28. What is the MOA for the Fluoroquinolones?
Only in limited amounts
severe orthostatic hypotension - blurred vision - constipation - sexual dysfunction
Chronic gout.
Inhibit DNA Gyrase (topoisomerase II) - Bactericidal

29. What are two toxicities associated with Cyclosporine?
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression
1. Predisposes to viral infections and lymphoma 2. Nephrotoxic (preventable with mannitol diuresis)
Sulfonylureas are oral hypoglycemic agents - they are used to stimulate release of endogenous insulin in NIDDM (type -2).
Nephrotoxicity (esp. with Cephalosporins) - Ototoxicity (esp. with Loop Diuretics)

30. List the specific antidote for this toxin: Methanol & Ethylene glycol
increased AP duration - increased ERP increased QT interval. Atrial and ventricular.
- Ethanol - dialysis - & fomepizole
Gram + cocci - Proteus mirabilis - E. coli - Klebsiella pneumoniae (PEcK)
Reversibly inhibits cyclooxygenase - mostly in CNS. Inactivated peripherally.

31. What is the category - desired effect - and period of use of albuterol in the treatment of Asthma?
Beta 2 agonist; desired effect is the relaxation of bronchial smooth muscle (Beta 2). Use during acute exacerbation.
narcolepsy - obesity - and attention deficit disorder (I wouldn't recommend this)
hyperchloremic metabolic acidosis - neuropathy - NH3 toxicity - sulfa allergy
- Flumazenil

32. What is the category of drug names ending in - azepam (e.g. Diazepam)
Benzodiazepine.
Norepinephrine
Anaerobic infections (e.g. - B. fragilis - C. perfringens)
Intrathecally

33. What is the category of drug names ending in - ipramine (e.g. Imipramine)
blocks SR Ca2+ channels
Diarrhea
alpha -1 > alpha -2; used as a pupil dilator - vasoconstrictor - and for nasal decongestion
Tricyclic antidepressant.

34. Is resistant to penicillinase?
- Shifts the curve to the right - increases Km
Imipenem
Beta1 more than B2
Rash - Pseudomembranous colitis

35. What is the MOA for Clindamycin?
Pregnant women - Children; because animal studies show Damage to Cartilage
Blocks Peptide Bond formation at the 50S subunit - Bacteriostatic
Antibiotic - protein synthesis inhibitor.
Protease inhibitor.

36. Name three Antiarrhythmic drugs in class IC.
- Normalize K+ - Lidocaine - & Anti - dig Mab
Digitoxin>95% Digoxin 75%
Giant Roundworm (Ascaris) - Hookworm (Necator/Ancylostoma) - Pinworm (Enterobius)
Flecainide - Encainide - Propafenone

37. List the mechanism - clinical use - & toxicity of Bleomycin.
NO AP duration effect. useful in V- tach that progresses to V- fib and in intractable SVT Last RESORT
Modification via Acetylation - Adenylation - or Phosphorylation
- DNA intercalator - testicular & lymphomas - Pulmonary fibrosis mild myelosuppression.
- Nitrate - hydroxocobalamin thiosulfate

38. Cocaine casues vasoconstriction and local anesthesia by What mechanism
Tubocurarine - atracurium - mivacurium - pancuronium - vecuronium - rapacuronium
Indirect agonist - uptake inhibitor
Terminal D- ala of cell wall replaced with D- lac; Decreased affinity
1. Buffalo hump 2. Moon facies 3. Truncal obesity 4. Muscle wasting 5. Thin skin 6. Easy bruisability 7. Osteoporosis 8. Adrenocortical atrophy 9. Peptic ulcers

39. Antimicrobial prophylaxis for Syphilis
Benzathine penicillin G
effective in torsade de pointes and digoxin toxicity
Inhibits xanthine oxidase - decresing conversion of xanthine to uric acid.
Tubocurarine - atracurium - mivacurium - pancuronium - vecuronium - rapacuronium

40. What additional side effects exist for Ampicillin?
1. Better bioavailability 2. 2 to 4 times longer half life 3. Can be administered subcutaneously 4. Does not require laboratory monitoring
Rash - Pseudomembranous colitis
Succinylcholine
Well tolerated in general but occasionally - Nephrotoxicity - Ototoxicity - Thrombophlebitis - diffuse flushing='Red Man Syndrome'

41. What is the MOA for the Macrolides?
Blocks translocation - binds to the 23S rRNA of the 50S subunit - Bacteriostatic
1. Gastric ulceration 2. Bleeding 3. Hyperventilation 4. Reye's syndrome 5. Tinnitus (CN VIII)
Prophylaxis for Influenza A - Rubella; Parkinson's disease
Inhibit viral DNA polymerase

42. Amprotericin B ___________ the BBB
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.)
- N- acetylcystine
NO AP duration effect. useful in V- tach that progresses to V- fib and in intractable SVT Last RESORT
Does not cross

43. What is Metronidazole used for clinically?
- Metronidazole - certain cephalosporins - procarbazine - sulfonylureas
Antiprotozoal: Giardia - Entamoeba - Trichomonas - Gardnerella vaginalis Anaerobes: Bacteroides - Clostridium
Gram + cocci - Haemophilus influenza - Enterobacter aerogenes - Neisseria species - P. mirabilis - E. coli - K. pneumoniae - Serratia marcescens ( HEN PEcKS )
NE increases bp - Which stimulates baroreceptors in the carotid sinus and the aorta. The CNS signals through vagal stimulation to decrease heart rate.

44. Which drug(s) cause this reaction: Tendonitis and rupture?
Inhibits IMP Dehydrogenase (competitively) - and therefore blocks Guanine Nucleotide synthesis
AluMINIMUM amount of feces.
Inhibits cell wall mucopeptide formation - Bactericidal
- Fluoroquinolones

45. Common side effects associated with Clindamycin include?
Amphotericin B - Nystatin - Fluconazole/azoles
distal convoluted tubule (early)
Pseudomembranous colitis (C. difficile) - fever - diarrhea
GI distress - Tooth discoloration and Inhibition of bone growth in children - Fanconi's syndrome - Photosensitivity

46. Toxic side effects of the Azoles?
Hormone synthesis inhibition (Gynecomastia) - Liver dysfunction (Inhibits CYP450) - Fever - Chills
Flutamide is a nonsteroidal competitive inhibitor of androgens at the testosterone receptor - used in prostate carcinoma.
The only local anesthetic with vasoconstrictive properties.
Rheumatoid and osteoarthritis.

47. What drug is used to diagnose myasthenia gravis?
Hypersensitivity reactions
edrophonium (extremely short acting anticholinesterase)
Gentamicin - Neomycin - Amikacin - Tobramycin - Streptomycin
pulmonary edema - dehydration

48. What is the memory key for the effect of magnesium hydroxide overuse?
Gram + and Anerobes
Mg = Must go to the bathroom.
- Isoniazid
- Deferoxamine

49. What are the clinical indications for neostigmine?
Inhibits cell wall mucopeptide formation - Bactericidal
Foscarnet = pyroFosphate analog
Post - op and neurogenic ileus and urinary retention - myasthenia gravis - and reversal of neuromuscular junction blockade (post - op) through anticholinesterase activity.
Nifedipine - Verapamil - Diltiazem

50. MOA: Block mRNA synthesis
Albuterol - tertbutaline
hyperkalemia - endocrine effects (gynecomastia - anti - androgen)
Increases mean - systolic - and diastolic bp - while there is little change in pulse pressure.
Rifampin