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 drug(s) cause this reaction: Extrapyramidal side effects (3)?
When pts have Low CD4+ (< 500 cells/cubic mm) or a High Viral Load
- Chlorpromazine - thioridazine - haloperidol
Norepinephrine (Alpha1 -2 and beta 1)
Oral

2. IV Penicillin
Penicillin - G
1) Serious Gram - infections resistant to other Beta lactams 2) Meningitis (most penetrate the BBB)
1. RNA pol inhibitor 2. Revs up P450 3. Red/orange body fluids 4. Rapid resistance if used alone
Misoprostol is a PGE1 analog that increases the production and secretion of the gastic mucous barrier.

3. How do you treat coma in the ER (4)?
severe orthostatic hypotension - blurred vision - constipation - sexual dysfunction
- Airway - Breathing - Circulation - Dextrose (thiamine & narcan) - ABCD
Mechanism unknown; possibly inhibits gluconeogenesis and increases glycolysis; effect is to decrease serum glucose levels
Blocks Peptide Bond formation at the 50S subunit - Bacteriostatic

4. Which Aminoglycoside is used for Bowel Surgery ?
Cryptococcal meningitis in AIDS patients and Candidal infections of all types
Neomycin
Lidocaine - Mexiletine - Tocainide
Vibrio cholerae Acne Chlamydia Ureaplasma Urealyticum Mycoplasma pneumoniae Borrelia burgdorferi (Lyme's) Rickettsia Tularemia

5. MOA: Block DNA topoisomerases
Chronic gout.
Quinolones
Ciprofloxacin - Norfloxacin - Ofloxacin - Grepafloxacin - Enoxacin - Nalidixic acid
Gram + and Anerobes

6. Antiarrhythmic class IV- toxicity?
constipation - flushing - edema - CV effects (CHF - AV block - sinus node depression) - and torsade de pointes (Bepridil)
impotence - exacerbation of asthma - CV effects - CNS effects - may mask hypoclycemia
Because they require some residual islet function.
They inhibit reuptake of NE at the nerve terminal (as does cocaine).

7. What is the category of drug names ending in - pril (e.g. Captopril)
ACE inhibitor.
Rifampin - Ethambutol - Streptomycin - Pyrazinamide - Isoniazid (INH)
dizziness - flushing - constipation (verapamil) - nausea
Receptors = D1=D2>beta>alpha - thus increasing heart rate (beta) and blood pressure (alpha vasoconstriction) while maintaining kidney perfusion (dopamine receptors)

8. What is the clinical use for Warfarin?
hypertension - angina - arrhythmias
Chronic anticoagulation.
Bacitracin - Vancomycin
Inhibits organification and coupling of thyroid hormone synthesis. Also decreases peripheral conversion of T4 to T3.

9. How does a competitive antagonist effect an agonist?
constipation - flushing - edema - CV effects (CHF - AV block - sinus node depression) - and torsade de pointes (Bepridil)
Antiprotozoal: Giardia - Entamoeba - Trichomonas - Gardnerella vaginalis Anaerobes: Bacteroides - Clostridium
hypokalemia - slight hyperlipidemia - hyperuricemia - lassitude - hypercalcemia - hyperglycemia
- Shifts the curve to the right - increases Km

10. What is the lab value used to monitor the effectiveness of Heparin therapy?
block Na+ channels in the cortical collecting tubule
The PTT.
Competitive inibitor of progestins at progesterone receptors.
In 4 half - lifes= (94%) T1/2 = (0.7x Vd)/CL

11. How does a noncompetitive antagonist effect an agonist?
- inhibits HGPRT (pur. Syn.) - Luk - Lymph
Increase target cell response to insulin.
- Shifts the curve down - reduces Vmax
Useful in muscle paralysis during surgery or mechanical ventilation.

12. What is the mechanism of action of the glucocorticoids?
Decrease the production of leukotrienes and protaglandins by inhibiting phospholipase A2 and expression of COX-2.
torsade de pointes
- Flumazenil
Prevents the release of ACh - Which results in muscle paralysis.

13. Antiarrhythmic class IV- effects?
- S- phase anti - metabolite folate analogue - Luk - Lymp - sarc - RA - & psoriasis / - Reversible myelosuppression
decrease conduction velocity - increase ERP - increase PR interval
Sulfonylureas are oral hypoglycemic agents - they are used to stimulate release of endogenous insulin in NIDDM (type -2).
Hypersensitivity reactions

14. Ethacrynic Acid - mechanism?
Pregnant women - Children; because animal studies show Damage to Cartilage
not a sulfonamide - but action is the same as furosemide
G6PD deficient individuals
Doxycycline - because it is fecally eliminated

15. How do the Protease Inhibitors work?
- Lithium
Inhibt Assembly of new virus by Blocking Protease Enzyme
GI distress - Skin rash - and Seizures at high plasma levels
decrease AP duration - affects ischemic or depolarized Purkinje and ventricular system

16. Name the steps in drug approval(4)?
Babiturate.
decrease myocardial O2 consumption by: 1- decreasing end diastolic volume 2- decreasing BP 3- decreasing HR 4- decreasing contractility 5- decreasing ejection time
- Phase I (clinical tests) - Phase II - Phase III - PhaseIV (surveillance)
- Quinidine - quinine

17. Adverse effects of Loop Diuretics?
1. Streptokinase 2. Urokinase 3. tPA (alteplase) - APSAC (anistreplase)
- EDTA - dimercaprol - succimer - & penicillamine
K+ wasting - metabolic alkalosis - hypotension - ototoxicity
- ED 50 is less than the Km (less than 50% of receptors)

18. Ca2+ sensitizers'- site of action?
Hormone synthesis inhibition (Gynecomastia) - Liver dysfunction (Inhibits CYP450) - Fever - Chills
troponin - tropomyosin system
Teratogenic - Carcinogenic - Confusion - Headaches
Blastomyces - Coccidioides - Histoplasma - C. albicans; Hypercortisolism

19. What is combined with Ampicillin - Amoxicillin - Carbenicillin - Piperacillin - and Ticarcillin to enhance their spectrum?
Used in combination therapy with SMZ to sequentially block folate synthesis
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
Clavulanic acid
Does not cross

20. What cholinomimetics might your pt be taking for his glaucoma
Carbachol - pilocarpine - physostigmine - echothiophate
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression
Primaquine
Gram + and Anerobes

21. List the specific antidote for this toxin: Tricyclic antidepressants
Methylxanthine.
Ipratropium
- NaHCO3
Depolymerizes microtubules - impairing leukocyte chemotaxis and degranulation.

22. What do you treat Nematode/roundworm (pinworm - whipworm) infections with?
Albuterol - tertbutaline
Mebendazole/Thiabendazole - Pyrantel Pamoate
Primaquine
Bacitracin - Vancomycin

23. What type of gout is treated with Allopurinol?
Binds ergosterol - Disrupts fungal membranes
- Clindamycin
No
Chronic gout.

24. What is Metronidazole combined with for 'triple therapy'? Against What organism?
Bismuth and Amoxicillin or Tetracycline; against Helobacter pylori
Doxycycline - because it is fecally eliminated
Ipratropium
1) Hypersensitivity reactions 2) Increased nephrotoxicity of Aminoglycosides 3) Disulfiram - like reaction with ethanol (those with a methylthiotetrazole group - e.g. - cefamandole)

25. The MOA for Chloramphenicol is?
Phenothiazine (neuroleptic - antiemetic).
Pretreat with antihistamines and a slow infusion rate
Inhibition of 50S peptidyl transferase - Bacteriostatic
Neurotoxicity - Acute renal tubular necrosis

26. Which drug(s) cause this reaction: Cinchonism (2)?
- Quinidine - quinine
- Niacin - Ca++ channel blockers - adenosine - vancomycin
Nephrotoxicity
- Sulfonamides - furosemide - methicillin - rifampin - NSAIDS (ex. ASA)

27. Decrease Digitoxin dose in renal failure?
Minor hepatotoxicity - Drug interactions (activates P450)
Misoprostol is contraindicated in women of childbearing potential because it is an abortifacient.
NO
constipation - flushing - edema - CV effects (CHF - AV block - sinus node depression) - and torsade de pointes (Bepridil)

28. Aztreonam is not usually...
1. Pioglitazone 2. Rosiglitazone.
Oral treatment of superficial infections
Peptic ulcer disease.
toxic

29. Dobutamine used for the tx of shock acts on Which receptors
Give an antichloinesterase - neostigmine - edrophonium - etc
Impairs the synthesis of vitamin K- dependent clotting factors
Misoprostol is a PGE1 analog that increases the production and secretion of the gastic mucous barrier.
Beta1 more than B2

30. Where does Griseofulvin deposit?
Buy AT 30 - CELL at 50'
Keratin containing tissues - e.g. - nails
Binds 30S subunit and prevents attachment of aminoacyl - tRNA - Bacteriostatic
Cimetidine is a potent inhibitor of P450; it also has an antiandrogenic effect and decreases renal excretion of creatinine. Other H2 blockers are relatively free of these effects.

31. MOA: Disrupt bacterial/fungal cell membranes
thiazides - amiloride
- Haloperidol - chlorpromazine - reserpine - MPTP
Keratin containing tissues - e.g. - nails
Polymyxins

32. What is the formula for Clearance (CL)
Antifungal.
Stimulates beta adrenergic receptors
- Corticosteroids - heparin
CL= (rate of elimination of drug/ Plasma drug conc.)

33. What is the MOA for the Cephalosporins?
- aminoglycosides - loop diuretics - cisplatin
Beta lactams - inhibit cell wall synthesis - Bactericidal
Staphlococcus aureus and Clostridium difficile (pseudomembranous colitis)
Treatment of infertility.

34. Explain differences between full and partial agonists(2).
GET on the Metro
Hormone synthesis inhibition (Gynecomastia) - Liver dysfunction (Inhibits CYP450) - Fever - Chills
Increases mean - systolic - and diastolic bp - while there is little change in pulse pressure.
- Act on same receptor - Full has greater efficacy

35. Which drug(s) cause this reaction: Torsade de pointes (2)?
Oxygen
- Class III antiarrhythmics (sotalol) - class IA (quinidine)
1. Acarbose 2. Miglitol
Aminoglycosides

36. What are common side effects of Protease Inhibitors?
GI intolerance (nausea - diarrhea) - Hyperglycemia - Lipid abnormalities - Thrombocytopenia (Indinavir)
Yes
1. Bleeding 2. Thrombocytopenia 3. Drug - drug interactions
PT

37. What are common toxicities related to Vancomycin therapy?

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

38. What reversal agent could a Anes give to reverse the effects of Atropine
With an amino acid change of D- ala D- ala to D- ala D- lac
vasodilator - increases cGMP to induce smooth muscle relaxation (arterioles>veins; afterload reduction)
Bethanechol - Neostigmine - physostigmine
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.

39. How is Griseofulvin used clinically?
Oral treatment of superficial infections
Epinephrine
Inhibits organification and coupling of thyroid hormone synthesis. Also decreases peripheral conversion of T4 to T3.
Atropine would also block the receptors in the ciliary muscle - causing an impairment in accommodation (cycloplegia).

40. Which drug(s) cause this reaction: Pseudomembranous colitis?
Cimetidine is a potent inhibitor of P450; it also has an antiandrogenic effect and decreases renal excretion of creatinine. Other H2 blockers are relatively free of these effects.
Decrease the production of leukotrienes and protaglandins by inhibiting phospholipase A2 and expression of COX-2.
Treatment of infertility.
- Clindamycin

41. What microorganisms are Aminoglycosides ineffective against?
sedation - depression - nasal stuffiness - diarrhea
Anaerobes
Inhibits cell wall synthesis ( binds to PBP3). A monobactam
Paranteral (IV - SC)

42. Why are albuterol and terbutaline effective in tx of acute asthmatic attacks?
1. Weight gain 2. Hepatotoxicity (troglitazone)
These B-2 agonists cause respiratory smooth muscle to relax.
Praziquantel
Ciprofloxacin - Norfloxacin - Ofloxacin - Grepafloxacin - Enoxacin - Nalidixic acid

43. Steady state concentration is reached in __ number of half - lifes
hypokalemia - slight hyperlipidemia - hyperuricemia - lassitude - hypercalcemia - hyperglycemia
- Upper respiratory tract infections - pneumonias - STDs: Gram+ cocci (streptococcal infect in pts allergic to penicillin) - Mycoplasma - Legionella - Chlamydia - Neisseria
fetal renal damage - hyperkalemia - Cough - Angioedema - Proteinuria - Taste changes - hypOtension - Pregnancy problems - Rash - Increased renin - Lower Angiotensin II (CAPTOPRIL)
In 4 half - lifes= (94%) T1/2 = (0.7x Vd)/CL

44. Preferential action of the Ca2+ channel blockers at vascular smooth muscle?
vascular sm. Mus.: Nifedipine>Diltiazem>Verapamil
Blocks Peptide Bond formation at the 50S subunit - Bacteriostatic
Edrophonium
cinchonism: HA - tinnitus - thrombocytopenia - torsade de pointes due to increased QT interval

45. What drug is used to diagnose myasthenia gravis?
Sulfonamide Loop Diuretic. Inhibits ion co - transport system of thick ascending loop. Abolishes hypertonicity of the medulla - thereby preventing concentration of the urine.
Nucleosides
edrophonium (extremely short acting anticholinesterase)
constipation - flushing - edema - CV effects (CHF - AV block - sinus node depression) - and torsade de pointes (Bepridil)

46. Name three Antiarrhythmic drugs in class IC.
Flecainide - Encainide - Propafenone
ACE inhibitor.
vascular sm. Mus.: Nifedipine>Diltiazem>Verapamil
1) Chloramphenical = bacteriostatic 2) Erythromycin = bacteriostatic 3) Lincomycin = bacteriostatic 4)cLindamycin = bacteriostatic

47. Why would a patient with cog - wheel rigidity and a shuffling gait be given benztropine?
Parkinson patients benefit from antimuscarinic agents through its inhibitory action within the indirect pathway.
Useful in muscle paralysis during surgery or mechanical ventilation.
- Barbiturates - phenytoin - carbamazipine - rifampin - griseofulvin - quinidine
NE acts presynaptically on alpha -2 receptors to inhibit its own release. ACh also acts presynaptically through M1 receptors to inhibit NE release.

48. List the mechanism - clinical use - & toxicity of Bleomycin.
atropine - homatropine - tropicamide
sedation - sleep alterations
Protamine sulfate
- DNA intercalator - testicular & lymphomas - Pulmonary fibrosis mild myelosuppression.

49. What is the MOA for the Aminoglycosides?
Inhibits formation of Initiation Complex - causes misreading of mRNA - Bactericidal
Protamine Sulfate is used for rapid reversal of heparinization (positively charged molecule that binds to negatively charged heparin).
increased AP duration - increased ERP increased QT interval. Atrial and ventricular.
- Protamine

50. What enzyme is responsible for the production of Ach from Acetyl CoA and Choline
- Chlorpromazine - thioridazine - haloperidol
Flutamide is a nonsteroidal competitive inhibitor of androgens at the testosterone receptor - used in prostate carcinoma.
Choline acetyltransferase
- Triggers apoptosis - CLL - Hodgkin's in MOPP - Cushing - like syndrome