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 is the mechanism of action of the thrombolytics?
- Steroids - Tamoxifen
Inhibits cell wall mucopeptide formation - Bactericidal
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.)
- Clindamycin

2. List the specific antidote for this toxin: Warfarin
Penicillin - Cephalosporins - Vancomycin - Aminoglycosides - Fluoroquinolones - Metronidazole
Chagas' disease - American Trypanosomiasis (Trypanosoma cruzi)
- Vitamin K & fresh frozen plasma
To inhibit renal Dihydropeptidase I and decrease Imipenem inactivation in the renal tubules

3. What is the category of drug names ending in - caine (e.g. Lidocaine)
Local anesthetic.
Modification via Acetylation
Paranteral (IV - SC)
Lipoxygenase

4. Name two bile acid resins.
Hemolytic anemia
- Chlorpromazine - thioridazine - haloperidol
Topical and Oral - for Oral Candidiasis (Thrush)
cholestyramine - colestipol

5. Which RT inhibitor causes Megaloblastic Anemia?
AZT
Hydralazine and Minoxidil
Digitoxin 168hrs Digoxin 40 hrs
toxic

6. Describe first - order kinetics?
Constant FRACTION eliminated per unit time.(exponential)
viral kinase
fetal renal damage - hyperkalemia - Cough - Angioedema - Proteinuria - Taste changes - hypOtension - Pregnancy problems - Rash - Increased renin - Lower Angiotensin II (CAPTOPRIL)
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.

7. What are the clinical uses for Imipenem/cilastatin?
Gram + cocci - Gram - rods - and Anerobes
1)Binds penicillin - binding proteins 2) Blocks transpeptidase cross - linking of cell wall 3) Activates autolytic enzymes
hypokalemia - slight hyperlipidemia - hyperuricemia - lassitude - hypercalcemia - hyperglycemia
- partial agonist can have increased - decreased - /A21or equal potency as full agonist. - Potency is an independent factor.

8. Resistance mechanisms for Macrolides

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

9. What are two types of drugs that interfere with the action of Sucralfate and why?
- Shifts the curve to the right - increases Km
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.
severe hypertension - CHF
VACUUM your Bed Room'

10. What is the mechanism of action of Ticlopidine - Clopidogrel
Choline acetyltransferase
Inhibits platelet aggregation by irreversibly inhibiting the ADP pathway involved in the binding of fibrinogen.
Pentamidine
- S- phase anti - metabolite folate analogue - Luk - Lymp - sarc - RA - & psoriasis / - Reversible myelosuppression

11. How do we stop angina?
Used in combination therapy with SMZ to sequentially block folate synthesis
No - hemicholinum block the uptake of Choline and thus Ach synthesis
decrease myocardial O2 consumption by: 1- decreasing end diastolic volume 2- decreasing BP 3- decreasing HR 4- decreasing contractility 5- decreasing ejection time
Nifedipine - Verapamil - Diltiazem

12. 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.
1. Pioglitazone 2. Rosiglitazone.
- Ethanol - dialysis - & fomepizole
Fever/Chills - Hypotension - Nephrotoxicity - Arrhythmias

13. Foscarnet does not require activation by a...
viral kinase
- Tetracycline - amiodarone - sulfonamides
anticholinesterase glaucoma
Treatment of hypertension - especially with renal disease (lowers bp centrally - so flow is maintained to kidney).

14. Norepi feedbacks and inhibits the presynaptic receptor by What mechanism
Fast vs. Slow Acetylators
- DNA intercalator - testicular & lymphomas - Pulmonary fibrosis mild myelosuppression.
Binding to the presynaptic alpha 2 release modulating receptors
dry mouth - sedation - severe rebound hypertension

15. Name the common Fluoroquinolones (6)
- Atropine & pralidoxime
AZT - to reduce risk of Fetal Transmission
Ciprofloxacin - Norfloxacin - Ofloxacin - Grepafloxacin - Enoxacin - Nalidixic acid
Ototoxicity - Hypokalemia - Dehydration - Allergy (sulfa) - Nephritis (interstitial) - Gout

16. What are signs of Sildenafil (Viagra) toxicity?
Acts as a wide spectrum carbapenem
Headache - flushing - dyspepsia - blue - green color vision.
Inhibits reabsorption of uric acid.
Hemolytic anemia

17. What are two processes Corticosteroids inhibit leading to decreased inflammation?
1) Hypersensitivity reactions 2) Increased nephrotoxicity of Aminoglycosides 3) Disulfiram - like reaction with ethanol (those with a methylthiotetrazole group - e.g. - cefamandole)
1. Phospholipase A2 is prevented from releasing arachidonic acid 2. Decreases protein synthesis thus lowering amount of Cyclooxygenase enzymes
Those patients who are taking nitrates.
GI distress - Skin rash - and Seizures at high plasma levels

18. Adverse effects of Captopril?
Antifungal.
1. Weight gain 2. Hepatotoxicity (troglitazone)
fetal renal toxicity - hyperkalemia - Cough - Angioedema - Proteinuria - Taste changes - hypOtension - Pregnancy problems - Rash - Increased renin - Lower Angiotensin II (CAPTOPRIL)
Tendonitis and Tendon rupture

19. What is the mechanism of action of Aspirin?
YES
1. Acarbose 2. Miglitol
- Chlorpromazine - thioridazine - haloperidol
Acetylates and irreversibly inhibits cyclooxygenase (COX I and COX II) to prevent the conversion of arachidonic acid to prostaglandins.

20. Why is Cilastatin administered with Imipenem?
proarrhythmic
Atropine pts are suffering from Cholinestrase inhibitor poisining (Nerve gas/Organophosphate poisining)
- DNA intercalator - testicular & lymphomas - Pulmonary fibrosis mild myelosuppression.
To inhibit renal Dihydropeptidase I and decrease Imipenem inactivation in the renal tubules

21. What is Niclosamide used for?
- acetylation - glucuron. - & sulfation - Conjugation - Polar product
Cestode/tapeworm (e.g. - D. latum - Taenia species Except Cysticercosis
- Alkalate DNA - Brain tumors - CNS toxicity
- Quinidine - quinine

22. Antiarrhythmic class IB- effects?
decrease AP duration - affects ischemic or depolarized Purkinje and ventricular system
Antileukotriene; blocks synthesis by lipoxygenase.
1) Chloramphenical = bacteriostatic 2) Erythromycin = bacteriostatic 3) Lincomycin = bacteriostatic 4)cLindamycin = bacteriostatic
nausea - headache - lupus - like syndrome - reflex tachycardia - angina - salt retention

23. What antimicrobial class is Aztreonam syngergestic with?
Aminoglycosides
Mg = Must go to the bathroom.
Digitoxin>95% Digoxin 75%
Systemic mycoses

24. How is Vancomycin used clinically?
Reversible block of histamine H2 receptors
GI intolerance (nausea - diarrhea) - Hyperglycemia - Lipid abnormalities - Thrombocytopenia (Indinavir)
Ibuprofen - Naproxen - and Indomethacin
For serious - Gram + multidrug - resistant organisms

25. Furosemide - clinical use?
HSV - VZV - EBV - Mucocutaneous and Genital Herpes Lesions - Prophylaxis in Immunocompromised pts
Clavulanic acid
edematous states (CHF - cirrhosis - nephrotic syndrome - pulm edema) - HTN - hypercalcemia
impotence - exacerbation of asthma - CV effects - CNS effects - may mask hypoclycemia

26. Hydralazine - clinical use?
severe hypertension - CHF
- S- phase anti - metabolite folate analogue - Luk - Lymp - sarc - RA - & psoriasis / - Reversible myelosuppression
Constant FRACTION eliminated per unit time.(exponential)
CL= (rate of elimination of drug/ Plasma drug conc.)

27. What is the MOA of Amantadine?
- Flumazenil
Neutropenia (ticlopidine); reserved for those who cannot tolerate aspirin.
Lipoxygenase
Blocks viral penetration/uncoating; may act to buffer the pH of the endosome

28. How do Sulfonamides act on bacteria?
Penicillin - G
- Chloramphenicol
As PABA antimetabolites that inhibit Dihydropteroate Synthase - Bacteriostatic
- Bleomycin - amiodarone - busulfan

29. What is the MOA of Griseofulvin?
Triple Therapy' 2 Nucleoside RT Inhibitors with a Protease Inhibitor
Interferes with microtubule function - disrupts mitosis - inhibits growth
Rifampin
- Upper respiratory tract infections - pneumonias - STDs: Gram+ cocci (streptococcal infect in pts allergic to penicillin) - Mycoplasma - Legionella - Chlamydia - Neisseria

30. Antiarrhythmic class IC- toxicity?
proarrhythmic
Antileukotriene; blocks synthesis by lipoxygenase.
Ipratropium
Antibiotic - protein synthesis inhibitor.

31. For Heparin What is the Route of administration
Hypersensitivity reactions
- Alkalinize urine & dialysis
Paranteral (IV - SC)
Similar to cyclosporine; binds to FK- binding protein - inhibiting secretion of IL-2 and other cytokines.

32. What microorganisms is Aztreonam not effective against?
- Atropine & pralidoxime
- Penicillin
INH: Injures Neurons and Hepatocytes
Gram + and Anerobes

33. Which drug(s) cause this reaction: Tubulointerstitial Nephritis (5)?
Nucleosides
Treatment of hypertension - especially with renal disease (lowers bp centrally - so flow is maintained to kidney).
TMP- SMZ (DOC) - aerosolized pentamidine
- Sulfonamides - furosemide - methicillin - rifampin - NSAIDS (ex. ASA)

34. Antimicrobial prophylaxis for Gonorrhea
Hydralazine and Minoxidil
Mycobacterium tuberculosis - the only agent used as solo prophylaxis against TB
Ceftriaxone
RESPIre

35. Cocaine shares is mechanism of action with What antidepressant
torsade de pointes - excessive Beta block
Carbachol - pilocarpine - physostigmine - echothiophate
TCA
Edrophonium

36. What are the side effects of Rifampin?
Decreased uptake or Increased transport out of cell
- Quinidine - quinine
Minor hepatotoxicity - Drug interactions (activates P450)
Triple sulfas or SMZ

37. MOA: Block peptidoglycan synthesis
Hydralazine and Minoxidil
anuria - CHF
Staphlococcus aureus and Clostridium difficile (pseudomembranous colitis)
Bacitracin - Vancomycin

38. What are three unwanted effects of Mifepristone?
1. Heavy bleeding 2. GI effects (n/v - anorexia) 3. Abdominal pain
Inhibit intestinal bursh border Alpha - glucosidases; delayed hydrolysis of sugars and absorption of sugars leading to decresed postprandial hyperglycemia.
Anaerobes
Edrophonium

39. Adverse effects of Loop Diuretics?
In 4 half - lifes= (94%) T1/2 = (0.7x Vd)/CL
- Oxalic acid - Acidosis & nephrotoxicity
K+ wasting - metabolic alkalosis - hypotension - ototoxicity
- Ethanol - dialysis - & fomepizole

40. What is the lab value used to monitor the effectiveness of Heparin therapy?
AluMINIMUM amount of feces.
The PTT.
Babiturate.
Give an antichloinesterase - neostigmine - edrophonium - etc

41. What is the mechanism of action of Warfarin (Coumadin)?
CMV Retinitis in IC pts When Ganciclovir fails
Systemic mycoses
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.
Inhibits bacterial Dihydrofolate Reductase - Bacteriostatic

42. MOA: Block nucleotide synthesis
Sulfonamides - Trimethoprim
Only in limited amounts
- polymyxins
1. Pioglitazone 2. Rosiglitazone.

43. What are the products and their toxicities of the metabolism of Ethylene Glycol by / alcohol dehydrogenase?
Reserpine inhibits dopamine transport into vesicles - attenuating its conversion to NE by dopamine beta - hydroxylase.
Erectile dysfunction.
- Oxalic acid - Acidosis & nephrotoxicity
Epinephrine

44. What are Aminoglycosides used for clinically?
aPTT (intrinsic pathway)
- Fluoroquinolones
Severe Gram - rod infections.
The PTT.

45. List the specific antidote for this toxin: Benzodiazepines
Cryptococcal meningitis in AIDS patients and Candidal infections of all types
Inhibit steroid synthesis - used in the treatment of polycystic ovarian syndrome to prevent hirsutism.
acts at the proximal convoluted tubule to inhibit carbonic anhydrase. Causes self - limited sodium bicarb diuresis and reduction of total body bicarb stores.
- Flumazenil

46. Are Ampicillin and Amoxicillin are not...
- Isoniazid
penicillinase resistant
Bismuth and Amoxicillin or Tetracycline; against Helobacter pylori
Parkinson patients benefit from antimuscarinic agents through its inhibitory action within the indirect pathway.

47. Name the common Aminoglycosides (5)
- reduction - oxy - & hydrolysis - H2O sol. Polar product - P450
Due to the presence of a bulkier R group
Gentamicin - Neomycin - Amikacin - Tobramycin - Streptomycin
Finasteride inhibits 5 Alpha - reductase - this decreases the conversion of testosterone to dihydrotestosterone - useful in BPH

48. How does resistance to Vancomycin occur?
Tubocurarine - atracurium - mivacurium - pancuronium - vecuronium - rapacuronium
Cell membrane Ca2+ channels of cardiac sarcomere
With an amino acid change of D- ala D- ala to D- ala D- lac
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.

49. How are the HIV drugs used clinically?

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

50. What organisms does Griseofulvin target?
Rifampin
Dermatophytes (tinea - ringworm)
Beta antagonist.
GET on the Metro