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. Which cancer drugs work at the level of mRNA(2)?
- Steroids - Tamoxifen
Gemfibrozil - Clofibrate
Edrophonium
impotence - asthma - CV effects (bradycardia - CHF - AV block) - CNS effects (sedation - sleep alterations)

2. Acetazolamide causes?

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

3. What is a possible result of overdose of Acetaminophen?
Give an antichloinesterase - neostigmine - edrophonium - etc
NE acts presynaptically on alpha -2 receptors to inhibit its own release. ACh also acts presynaptically through M1 receptors to inhibit NE release.
- Oxalic acid - Acidosis & nephrotoxicity
Overdose produces hepatic necrosis; acetaminophen metablolite depletes glutathione and forms toxic tissue adducts in liver.

4. A group of pts are rushed into the ER complaining of excessive sweating - tearing - salivation - HA - N and V - muscle twitching - difficulty breathing and diarrhea. What drug would be the most effective immediate tx
- Penicillamine
Atropine pts are suffering from Cholinestrase inhibitor poisining (Nerve gas/Organophosphate poisining)
Decreased uptake or Increased transport out of cell
- Tamoxifen

5. List the specific antidote for this toxin: Heparin
- Protamine
Albuterol - tertbutaline
WEPT: Warfarin affects the Extrinsic pathway and prolongs the PT.
Minor hepatotoxicity - Drug interactions (activates P450)

6. List the specific antidote for this toxin: Amphetamine
- Antipsychotics
Diarrhea
pulmonary edema - dehydration
- Ammonium Chloride

7. Decrease Digitoxin dose in renal failure?
Carbenicillin - Piperacillin - and Ticarcillin
Bethanechol - Neostigmine - physostigmine
loop diuretics - spironolactone
NO

8. How does botulinum toxin result in respiratory arrest?
Praziquantel
NE increases bp - Which stimulates baroreceptors in the carotid sinus and the aorta. The CNS signals through vagal stimulation to decrease heart rate.
Prevents the release of ACh - Which results in muscle paralysis.
NO HYPERURICEMIA - NO SULFA AllERGY; same as furosemide otherwise

9. Which cancer drugs inhibit nucleotide synthesis(3)?
- DNA intercalator - Hodgkin's - myeloma - sarcoma - and solid tumors - Cardiotoxicity & alopecia
first dose orthostatic hypotension - dizziness - headache
- Methotrexate - 5 FU - 6 mercaptopurine
anuria - CHF

10. What is a common drug interaction associated with Griseofulvin?
Theoretically it could be used to block the cephalic phase of acid secretion (vagal stimulation).
edematous states (CHF - cirrhosis - nephrotic syndrome - pulm edema) - HTN - hypercalcemia
Increases coumadin metabolism
Prefers beta's at low doses - but at higher doses alpha agonist effects are predominantly seen.

11. What is a common side effect of Colchicine used to treat acute gout - especially When given orally?
Treatment of infertility.
sedation - depression - nasal stuffiness - diarrhea
GI side effects. (Indomethacin is less toxic - more commonly used.)
Fast vs. Slow Acetylators

12. For Warfarin What is the Site of action
Liver
amphetamine and ephedrine
Benzodiazepine.
cardiac muscle: Verapamil>Diltiazem>Nifedipine

13. What are three possible toxicities of NSAID usage?
Butyrophenone (neuroleptic).
- Corticosteroids - heparin
1. Renal damage 2. Aplastic anemia 3. GI distress
Gram + cocci - Haemophilus influenza - Enterobacter aerogenes - Neisseria species - P. mirabilis - E. coli - K. pneumoniae - Serratia marcescens ( HEN PEcKS )

14. Which cancer drugs effect nuclear DNA (4)?
Aminoglycosides - Tetracyclines
Phase 1 = prolonged depolarization - no antidote - effect potentiated by anticholinesterase; Phase 2 = repolarized but blocked - an anticholinesterase is the antidote for this phase.
- Alkalating agents+cisplatin - Doxorubicin+Dactinomycin - Bleomycin - Etoposide
Bismuth and Amoxicillin or Tetracycline; against Helobacter pylori

15. Which of epi - norepi - or isoproterenol results in bradycardia?
Antileukotriene; blocks leukotriene receptors.
Indomethacin is used to close a patent ductus arteriosus.
- Quinidine - quinine
Norepinephrine

16. Acetaldehyde is metabolized by Acetaldehyde dehydrogenase - Which drug inhibs this enzyme?
sedation - positive Coombs' test
- Disulfram & also sulfonylureas - metronidazole
- Airway - Breathing - Circulation - Dextrose (thiamine & narcan) - ABCD
They inhibit reuptake of NE at the nerve terminal (as does cocaine).

17. What are three toxicities of Propylthiouracil?
Pretreat with antihistamines and a slow infusion rate
The only local anesthetic with vasoconstrictive properties.
1. Skin rash 2. Agranulocytosis (rare) 3. Aplastic anemia
1) Chloramphenical = bacteriostatic 2) Erythromycin = bacteriostatic 3) Lincomycin = bacteriostatic 4)cLindamycin = bacteriostatic

18. What is the main clinical use for the thrombolytics?
loop diuretics - spironolactone
Dermatophytes (tinea - ringworm)
Early myocardial infarction.
Leukopenia - Neutropenia - Thrombocytopenia - Renal toxicity

19. List the mechanism - clinical use - & toxicity of Vincristine.

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

20. Antimicrobial prophylaxis for PCP
Misoprostol is contraindicated in women of childbearing potential because it is an abortifacient.
Inhibits CMV DNA polymerase
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.
TMP- SMZ (DOC) - aerosolized pentamidine

21. What enzyme does Zileuton inhibit?
Hypersensitivity reactions
Lipoxygenase
Initially vasoconstriction would increase bp - but then it acts on central alpha -2 receptors to decrease adrenergic outflow resulting in decreased bp.
Buy AT 30 - CELL at 50'

22. Name the common Azoles
Inhibits IMP Dehydrogenase (competitively) - and therefore blocks Guanine Nucleotide synthesis
- Alkalates DNA - CML - Pulmonary fibrosis hyperpigmentation
Fluconazole - Ketoconazole - Clotrimazole - Miconazole - Itraconazole
vascular sm. Mus.: Nifedipine>Diltiazem>Verapamil

23. What is the memory key for the effect of magnesium hydroxide overuse?
- Alkalate DNA - Brain tumors - CNS toxicity
Mg = Must go to the bathroom.
Anaerobes
G6PD deficient individuals

24. What is Ketoconazole specifically used for?
Blastomyces - Coccidioides - Histoplasma - C. albicans; Hypercortisolism
decrease the slope of phase 4 - increase PR interval (the AV node is particularly sensitive)
hyperkalemia - endocrine effects (gynecomastia - anti - androgen)
Activates antithrombin III

25. What organisms does Griseofulvin target?
Dermatophytes (tinea - ringworm)
Na/K ATPase
- Penicillin
Buy AT 30 - CELL at 50'

26. What are Aminoglycosides used for clinically?
- Tetracycline - amiodarone - sulfonamides
Reversibly inhibit cyclooxygenase (COX I and COX II). Block prostaglandin synthesis.
- acetylation - glucuron. - & sulfation - Conjugation - Polar product
Severe Gram - rod infections.

27. Which diuretics increase urine NaCl?
decrease myocardial O2 consumption by: 1- decreasing end diastolic volume 2- decreasing BP 3- decreasing HR 4- decreasing contractility 5- decreasing ejection time
propanolol - esmolol - metoprolol - atenolol - timolol
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.
all of them

28. Oral Penicillin
amphetamine and ephedrine
Penicillin - V
Onchocerciasis ('river blindness'-- rIVER- mectin)
Gemfibrozil - Clofibrate

29. List the mechanism - clinical use - & toxicity of Tamoxifen.
- Niacin - Ca++ channel blockers - adenosine - vancomycin
- Alkalate DNA - Brain tumors - CNS toxicity
- Estrogen receptor antagonist - Breast CA - increased endometrial CA risk
Interferes with microtubule function - disrupts mitosis - inhibits growth

30. MOA: Block protein synthesis at 30s subunit
Doxycycline - because it is fecally eliminated
GI upset - Superinfections - Skin rashes - Headache - Dizziness
- Bleomycin - amiodarone - busulfan
Aminoglycosides - Tetracyclines

31. What are common side effects of Amphotericin B?
- Formaldehyde & formic acid - severe acidosis & retinal damage
Inhibit intestinal bursh border Alpha - glucosidases; delayed hydrolysis of sugars and absorption of sugars leading to decresed postprandial hyperglycemia.
Fever/Chills - Hypotension - Nephrotoxicity - Arrhythmias
Prevents release of mediators from mast cells. Effective only for the prophylaxis of asthma. Not effective during an acute attack.

32. How is Amphotericin B administered for fungal meningitis?
1. Peptic ulcer 2. Gastritis 3. Esophageal reflux 4. Zollinger - Ellison syndrome
Local anesthetic.
- Daunorubicin & Doxorubicin
Intrathecally

33. What microorganisms are clinical indications for Tetracycline therapy?

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

34. K+ sparing diuretics - clinical use?
Doxycycline - because it is fecally eliminated
increase AP duration - increase ERP - increase QT interval - for use When other arrhythmics fail
carbonic anhydrase inhibitors - K+ sparing diuretics
hyperaldosteronism - K+ depletion - CHF

35. Adverse effects of Methyldopa?

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

36. For Warfarin What is the Mechanism of action
Impairs the synthesis of vitamin K- dependent clotting factors
- reduction - oxy - & hydrolysis - H2O sol. Polar product - P450
Alpha -1 antagonist
- Topo II inhibitor(GII specific) - Oat cell of Lung & prostate - & testicular - Myelosuppression & GI irritation.

37. What is the mechanism of action of the glucocorticoids?
Babiturate.
Abortifacient.
Decrease the production of leukotrienes and protaglandins by inhibiting phospholipase A2 and expression of COX-2.
decrease conduction velocity - increase ERP - increase PR interval

38. Antiarrhythmic class IV- effects?
Tricyclic antidepressant.
Fast vs. Slow Acetylators
These B-2 agonists cause respiratory smooth muscle to relax.
decrease conduction velocity - increase ERP - increase PR interval

39. In What population does Gray Baby Syndrome occur? Why?
depresses ectopic pacemakers - especially in digoxin toxicity
Premature infants - because they lack UDP- glucuronyl transferase
block voltage dependent L- type Ca2+ channels of cardiac and smooth muscle - decreasing contractility
Inhibits reabsorption of uric acid.

40. Are penicillinase resistant
Fast vs. Slow Acetylators
Methicillin - Nafcillin - and Dicloxacillin
Pralidoxime regenerates active cholinesterase.
No - warfarin - unlike heparin - can cross the placenta.

41. Preferential action of the Ca2+ channel blockers at cardiac muscle?
Wide spectrum of systemic mycoses: Cryptococcus - Blastomyces - Coccidioides - Aspergillus - Histoplasma - Candida - Mucor
cardiac muscle: Verapamil>Diltiazem>Nifedipine
reversible SLE- like syndrome
proximal convoluted tubule

42. Nifedipine has similar action to?
Nitrates
Competitive inibitor of progestins at progesterone receptors.
Well tolerated in general but occasionally - Nephrotoxicity - Ototoxicity - Thrombophlebitis - diffuse flushing='Red Man Syndrome'
Ibuprofen - Naproxen - and Indomethacin

43. Which Tetracycline is used in patients with renal failure? / Why?
amphetamine and ephedrine
Doxycycline - because it is fecally eliminated
Treatment of infertility.
Antimetabolite derivative of 6- mercaptopurine that interferes with the metablolism and synthesis of nucleic acid.

44. What is an acronym to remember Anti - TB drugs?
Headache - flushing - dyspepsia - blue - green color vision.
Chagas' disease - American Trypanosomiasis (Trypanosoma cruzi)
RESPIre
proarrhythmic

45. What is the mechanism of action of the Sulfonylureas?
Lidocaine - Mexiletine - Tocainide
Activates cholinergic receptors on bladder and bowel smooth muscle - alleviating post - op and neurogenic ileus and urinary retention.
- Topo II inhibitor(GII specific) - Oat cell of Lung & prostate - & testicular - Myelosuppression & GI irritation.
Close K+ channels in Beta - cell membrane leading to cell depolarization causing insulin release triggered by increase in Calcium ion influx.

46. What musculo - skeletal side effects in Adults are associated with Floroquinolones?
Tendonitis and Tendon rupture
hypertension - CHF - diabetic renal disease
ARF - shock - drug overdose - decrease intracranial/intraocular pressure
GI disturbances.

47. Do Tetracyclines penetrate the CNS?
Rheumatoid and osteoarthritis.
Erectile dysfunction.
Only in limited amounts
amphetamine and ephedrine

48. Adverse effects of Hydrochlorothiazide?
No - hemicholinum block the uptake of Choline and thus Ach synthesis
hypokalemia - slight hyperlipidemia - hyperuricemia - lassitude - hypercalcemia - hyperglycemia
Parkinson patients benefit from antimuscarinic agents through its inhibitory action within the indirect pathway.
Sulfonamide Loop Diuretic. Inhibits ion co - transport system of thick ascending loop. Abolishes hypertonicity of the medulla - thereby preventing concentration of the urine.

49. What are five disadvantages of Oral Contraceptives (synthetic progestins - estrogen)?
AZT
decrease conduction velocity - increase ERP - increase PR interval
1. Taken daily 2. No protection against STDs 3. Raises triglycerides 4. Depression - weight gain - nausea - HTN 5. Hypercoagulable state
Short.

50. What is the formula for Clearance (CL)
Immediate anticoagulation for PE - stroke - angina - MI - DVT.
Recurrent UTIs - Shigella - Salmonella - Pneumocystis carinii pneumonia
CL= (rate of elimination of drug/ Plasma drug conc.)
Antibiotic - protein synthesis inhibitor.