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 mecanism of action of Sucralfate?
- Formaldehyde & formic acid - severe acidosis & retinal damage
Benzodiazepine.
Aluminum sucrose sulfate polymerizes in the acid environment of the stomach and selectively binds necrotic peptic ulcer tissue. Acts as a barrier to acid - pepsin - and bile.
Hemolytic anemia

2. K+ sparing diuretics - toxicity?
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.
Ototoxicity - Hypokalemia - Dehydration - Allergy (sulfa) - Nephritis (interstitial) - Gout
hyperkalemia - endocrine effects (gynecomastia - anti - androgen)
GnRH analog with agonist properties When used in pulsatile fashion and antagonist properties When used in continuous fashion - causing a transient initial burst of LH and FSH

3. What is the effect of the Glitazones in diabetes treatment?
No
Rifampin
Acetaminophen has antipyretic and analgesic properties - but lacks anti - inflammatory properties.
Increase target cell response to insulin.

4. What is the clinical use for Sildenafil (Viagra)?
check PFTs - LFTs - and TFTs
first dose orthostatic hypotension - dizziness - headache
Erectile dysfunction.
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression

5. Why are Methicillin - Nafcillin - and Dicloxacillin penicillinase resistant?
Chronic gout.
decrease
Due to the presence of a bulkier R group
Butyrophenone (neuroleptic).

6. What is the MOA for Rifampin?
sedation - positive Coombs' test
cross - allergenic
Similar to cyclosporine; binds to FK- binding protein - inhibiting secretion of IL-2 and other cytokines.
Inhibits DNA dependent RNA polymerase

7. Which drug(s) cause this reaction: Cinchonism (2)?
- Quinidine - quinine
Penicillin - V
Ototoxicity - Hypokalemia - Dehydration - Allergy (sulfa) - Nephritis (interstitial) - Gout
Increase target cell response to insulin.

8. What are major side effects of Methicillin - Nafcillin - and Dicloxacillin?
Hypersensitivity reactions
- MT polymerization stabilizer - Ovarian & breast CA - Myelosupperession & hypersensitivity.
Increase target cell response to insulin.
- Weak Acids>Alkinalize urine(CO3) to remove more - Weak bases>acidify urine to remove more

9. What are two indirect acting adrenergic agonists?
Milk or Antacids - because divalent cations inhibit Tetracycline absorption in the gut
Binds Ergosterol - forms Membrane Pores that Disrupt Homeostatis
Megaloblastic anemia - Leukopenia - Granulocytopenia
amphetamine and ephedrine

10. Ibutilide - toxicity?
proarrhythmic
torsade de pointes
vasodilator - increases cGMP to induce smooth muscle relaxation (arterioles>veins; afterload reduction)
1. Aluminum hydroxide: constipation and hypophosphatemia 2. Magnesium hydroxide: diarrhea 3. Calcium carbonate: Hypercalcemia - rebound acid increase - All may cause hypokalemia

11. Cocaine shares is mechanism of action with What antidepressant
TCA
Ipratropium
Decrease the production of leukotrienes and protaglandins by inhibiting phospholipase A2 and expression of COX-2.
check PFTs - LFTs - and TFTs

12. What are the clinical indications for bethanechol?
1. Suppresses organ rejection after transplantation 2. Selected autoimmune disorders.
increase AP duration - increase ERP - increase QT interval - for use When other arrhythmics fail
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression
Activates cholinergic receptors on bladder and bowel smooth muscle - alleviating post - op and neurogenic ileus and urinary retention.

13. What is combined with Ampicillin - Amoxicillin - Carbenicillin - Piperacillin - and Ticarcillin to enhance their spectrum?
Clavulanic acid
Hypersensitivity reactions
- Ethosuxamide - sulfonamides - lamotrigine
Diarrhea - Urination - Miosis - Bronchospasm - Bradycardia - Excitation of skeletal muscle and CNS - Lacrimation - Sweating - and Salivation = DUMBBELS; also abdominal cramping

14. What is the MOA of Ganciclovir?
Cyclooxygenases (COX I - COX II).
Give an antichloinesterase - neostigmine - edrophonium - etc
Sulfonamides - Trimethoprim
Inhibits CMV DNA polymerase

15. What is the category of drug names ending in - caine (e.g. Lidocaine)
PT
Hypersensitivity reactions
scopolamine
Local anesthetic.

16. For Heparin What is the Treatment for overdose
Protamine sulfate
1. Suppresses organ rejection after transplantation 2. Selected autoimmune disorders.
acts at the proximal convoluted tubule to inhibit carbonic anhydrase. Causes self - limited sodium bicarb diuresis and reduction of total body bicarb stores.
diuretics - sympathoplegics - vasodilators - ACE inhibitors - Angiotensin II receptor inhibitors

17. For Heparin What is the Duration of action
Penicillin - G
Acute (hours)
- Tetracycline - amiodarone - sulfonamides
- S- phase anti - metabolite folate analogue - Luk - Lymp - sarc - RA - & psoriasis / - Reversible myelosuppression

18. List the mechanism - clinical use - & toxicity of Etoposide.
Inhibits CMV DNA polymerase
Corticosteroids; prevent production of leukotrienes from arachodonic acid by blocking phospholipase A2. Drugs of choice in a patient with status asthmaticus (in combination with albuterol.)
- Topo II inhibitor(GII specific) - Oat cell of Lung & prostate - & testicular - Myelosuppression & GI irritation.
Chronic (weeks or months)

19. How is Ribavirin used clinically?
Decreased uptake or Increased transport out of cell
Cephalosporin: 1) has a 6 member ring attached to the Beta lactam instead of a 5 member ring 2)has an extra functional group ( attached to the 6 member ring)
Spironolactone - Triamterene - Amiloride (the K+ STAys)
for RSV

20. MOA: Disrupt bacterial/fungal cell membranes
No - warfarin - unlike heparin - can cross the placenta.
Ataxia - Dizziness - Slurred speech
Polymyxins
pulmonary fibrosis - corneal deposits - hepatotoxicity - skin deposits resulting in photodermatitis - neurologic effects - consitpation - CV (bradycardia - heart block - CHF) - and hypo - or hyperthyroidism.

21. What are the products and their toxicities of the metabolism of Ethylene Glycol by / alcohol dehydrogenase?
Inhibits IMP Dehydrogenase (competitively) - and therefore blocks Guanine Nucleotide synthesis
- Clindamycin
Binds 30S subunit and prevents attachment of aminoacyl - tRNA - Bacteriostatic
- Oxalic acid - Acidosis & nephrotoxicity

22. Beta Blockers - site of action?
Beta adrenergic receptors and Ca2+ channels (stimulatory)
all except the K+ sparing diuretics Spironolactone - Triamterene - Amiloride
Misoprostol is a PGE1 analog that increases the production and secretion of the gastic mucous barrier.
Sulfonylureas are oral hypoglycemic agents - they are used to stimulate release of endogenous insulin in NIDDM (type -2).

23. What are the clinical uses for Imipenem/cilastatin?
Similar to cyclosporine; binds to FK- binding protein - inhibiting secretion of IL-2 and other cytokines.
Gram + cocci - Gram - rods - and Anerobes
- Weak Acids>Alkinalize urine(CO3) to remove more - Weak bases>acidify urine to remove more
GI discomfort

24. Why is there a drop in systolic - mean - and diastolic bp with infusion of isoproterenol?
1. Bleeding 2. Thrombocytopenia 3. Drug - drug interactions
Hexamethonium is a nicotinic antagonist - and thus is a ganglionic blocker.
Hypokalemic metabolic alkalosis - hyponatremia - hyperGlycemia - hyperLipidemia - hyperUricemia - hyperCalcemia - sulfa allergy.
Stimulating beta receptors stimulates heart rate - but beta receptor induced vasodilation reduces peripheral resistance.

25. List the mechanism - clinical use - & toxicity of Bleomycin.
decrease AP duration - affects ischemic or depolarized Purkinje and ventricular system
- DNA intercalator - testicular & lymphomas - Pulmonary fibrosis mild myelosuppression.
- Alkalating agent - NHL - Breast - ovary - & lung. - Myelosuppression - & hemorrhagic cystitis.
Antifungal.

26. Does Ampicillin or Amoxicillin have a greater oral bioavailability?
Chagas' disease - American Trypanosomiasis (Trypanosoma cruzi)
AmOxicillin has greater Oral bioavailability
post MI and digitalis induced arrhythmias
Headache - flushing - dyspepsia - blue - green color vision.

27. What is the clinical use for Warfarin?
torsade de pointes - excessive Beta block
CMV - esp in Immunocompromised patients
Chronic anticoagulation.
Spironolactone - Triamterene - Amiloride (the K+ STAys)

28. How is Trimethoprim used clinically?
- Chloramphenicol - benzene - NSAIDS - PTU - phenytoin
- Alkalating agents+cisplatin - Doxorubicin+Dactinomycin - Bleomycin - Etoposide
- Daunorubicin & Doxorubicin
Used in combination therapy with SMZ to sequentially block folate synthesis

29. What is Clindamycin used for clinically?
GnRH analog with agonist properties When used in pulsatile fashion and antagonist properties When used in continuous fashion - causing a transient initial burst of LH and FSH
Anaerobic infections (e.g. - B. fragilis - C. perfringens)
Antifungal.
Centrally acting alpha agonist - thus causing a decrease in central adrenergic outflow - spairing renal blood flow

30. What is the effect of epinephrine infusion on bp and pulse pressure?
- Normalize K+ - Lidocaine - & Anti - dig Mab
decrease
atropine - homatropine - tropicamide
Increased systolic and pulse pressure - decreased diastolic pressure - and little change in mean pressure.

31. What is the mechanism of action and clinical use of the antiandrogen Flutamide?
1. Bleeding 2. Teratogenicity 3. Drug - drug interactions
Flutamide is a nonsteroidal competitive inhibitor of androgens at the testosterone receptor - used in prostate carcinoma.
Indirect agonist - uptake inhibitor
- Tetracycline

32. Acetazolamide - toxicity?
Pentamidine
Rare.
hyperchloremic metabolic acidosis - neuropathy - NH3 toxicity - sulfa allergy
proarrhythmic

33. Oral Penicillin
Acetylcholinesterase; ACh is broken down into choline and acetate.
Penicillin - V
Pseudomonas species and Gram - rods
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.

34. When is HIV therapy initiated?
Digitoxin>95% Digoxin 75%
Beta antagonist.
AV nodal cells
When pts have Low CD4+ (< 500 cells/cubic mm) or a High Viral Load

35. Sotalol - toxicity?
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.
torsade de pointes - excessive Beta block
Yes
Bind cell membrane - disrupt osmotic properties - Are Cationc - Basic and act as detergents

36. What is the category of drug names ending in - triptyline (e.g. Amitriptyline)
Tricyclic antidepressant.
Inhibit steroid synthesis - used in the treatment of polycystic ovarian syndrome to prevent hirsutism.
Delirium - Tremor - Nephrotoxicity
Inhibits formation of Initiation Complex - causes misreading of mRNA - Bactericidal

37. Which drug(s) cause this reaction: Hepatitis?
competitive inhibirot of aldosterone in the cortical collecting tubule
1) Chloramphenical = bacteriostatic 2) Erythromycin = bacteriostatic 3) Lincomycin = bacteriostatic 4)cLindamycin = bacteriostatic
- Isoniazid
Anaerobic infections (e.g. - B. fragilis - C. perfringens)

38. Antiarrhythmic class II- mechanism?
carbonic anhydrase inhibitors - K+ sparing diuretics
blocking the beta adrenergic receptor leads to decreased cAMP - and decreased Ca2+ flux
- B51Naloxone / naltrexone (Narcan)
Competitive inibitor of progestins at progesterone receptors.

39. When is Rifampin not used in combination with other drugs?
Peptic ulcer disease.
Gram + and Anerobes
Edrophonium
1. Meningococcal carrier state 2. Chemoprophylaxis in contacts of children with H. influenzae type B

40. What is Imipenem always administered with?
Cilastatin
anuria - CHF
bradycardia - AV block - CHF
Chronic Hepatitis A and B - Kaposi's Sarcoma

41. Foscarnet does not require activation by a...
Mg = Must go to the bathroom.
cardiac depression - peripheral edema - flushing - dizziness - constipation
viral kinase
Rheumatoid and osteoarthritis.

42. What is treated with Chloroquine - Quinine - Mefloquine?
Mg = Must go to the bathroom.
Chronic gout.
Extended spectrum penicillin: certain Gram + bacteria and Gram - rods
Malaria (P. falciparum)

43. What Sulfonamides are used for simple UTIs?
Triple sulfas or SMZ
- Alkalating agents+cisplatin - Doxorubicin+Dactinomycin - Bleomycin - Etoposide
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.)
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression

44. What is the clinical use for Nystatin?
Topical and Oral - for Oral Candidiasis (Thrush)
-100% oxygen - hyperbaric
increased AP duration - increased ERP increased QT interval. Atrial and ventricular.
ACIDazolamide' causes acidosis

45. What is the MOA for Carbenicillin - Piperacillin - and Ticarcillin?
Onchocerciasis ('river blindness'-- rIVER- mectin)
These B-2 agonists cause respiratory smooth muscle to relax.
Bethanechol - Neostigmine - physostigmine
Same as penicillin. Extended spectrum antibiotics

46. What is the effect of guanethidine on adrenergic NE release?
Because they require some residual islet function.
It inhibits release of NE.
Neostigmine - pyridostigmine edrophonium - physostigmine echothiophate
Binds to the Pyrophosphate Binding Site of the enzyme

47. What is the clinical use for Penicillin?
Pretreat with antihistamines and a slow infusion rate
Bactericidal for: Gram + rod and cocci - Gram - cocci - and Spirochetes
Sotalol - Ibutilide - Bretylium - Amiodarone
- Upper respiratory tract infections - pneumonias - STDs: Gram+ cocci (streptococcal infect in pts allergic to penicillin) - Mycoplasma - Legionella - Chlamydia - Neisseria

48. What is the enzyme inhibited - the effect of this inhibition - and the clinical use of the antiandrogren Finasteride?
1. Predisposes to viral infections and lymphoma 2. Nephrotoxic (preventable with mannitol diuresis)
vasodilator - increases cGMP to induce smooth muscle relaxation (arterioles>veins; afterload reduction)
Resistant Gram - infections
Finasteride inhibits 5 Alpha - reductase - this decreases the conversion of testosterone to dihydrotestosterone - useful in BPH

49. What microorganisms is Aztreonam not effective against?
Gram + and Anerobes
Treatment of hypertension - especially with renal disease (lowers bp centrally - so flow is maintained to kidney).
Aplastic anemia (dose independent) - Gray Baby Syndrome
Dopamine; causes its release from intact nerve terminals

50. What are the indications for using amphetamine?

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