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. MOA for Penicillin (3 answers)?
- DNA intercalator - testicular & lymphomas - Pulmonary fibrosis mild myelosuppression.
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.)
1)Binds penicillin - binding proteins 2) Blocks transpeptidase cross - linking of cell wall 3) Activates autolytic enzymes
TMP- SMZ (DOC) - aerosolized pentamidine

2. Ethacrynic Acid - clinical use?
Pretreat with antihistamines and a slow infusion rate
Diuresis in pateints with sulfa allergy
dizziness - flushing - constipation (verapamil) - nausea
NE acts presynaptically on alpha -2 receptors to inhibit its own release. ACh also acts presynaptically through M1 receptors to inhibit NE release.

3. Which drug(s) cause this reaction: Cardiac toxicity?
Prevents the release of calcium from the sarcoplasmic reticulum of skeletal muscle.
Alpha -1 antagonist
- Daunorubicin & Doxorubicin
Sulfonylureas are oral hypoglycemic agents - they are used to stimulate release of endogenous insulin in NIDDM (type -2).

4. What is Clindamycin used for clinically?
- Alkalating agent - testicular - bladder - ovary -& lung - Nephrotoxicity & CN VIII damage.
1. Hot flashes 2. Ovarian enlargement 3. Multiple simultaneous pregnancies 4. Visual disturbances
Modification via Acetylation
Anaerobic infections (e.g. - B. fragilis - C. perfringens)

5. What is the category of drug names ending in - phylline (e.g. Theophylline)
Pentavalent Antimony
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia
Carbachol - pilocarpine - physostigmine - echothiophate
Methylxanthine.

6. What effect would atropine have on the preganglionic sympathetic activation of sweat glands? Would this person sweat?
None. No - because atropine would block the postganglionic muscarinic receptors involved in sweat gland stimulation.
increased AP duration - increased ERP increased QT interval. Atrial and ventricular.
Prevents release of mediators from mast cells. Effective only for the prophylaxis of asthma. Not effective during an acute attack.
They activate the ciliary muscle of the eye (open angle) and pupillary sphincter (narrow angle).

7. Preferential action of the Ca2+ channel blockers at cardiac muscle?
Enterobacter
As PABA antimetabolites that inhibit Dihydropteroate Synthase - Bacteriostatic
cardiac muscle: Verapamil>Diltiazem>Nifedipine
1. In liver - increases storage of glucose as glycogen. 2. In muscle - stimulates glycogen and protein synthesis - and K+ uptake. 3. In adipose tissue - facilitates triglyceride storage.

8. What is the MOA of Amantadine?
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia
1. Renal damage 2. Aplastic anemia 3. GI distress
Blocks viral penetration/uncoating; may act to buffer the pH of the endosome
1) Chloramphenical = bacteriostatic 2) Erythromycin = bacteriostatic 3) Lincomycin = bacteriostatic 4)cLindamycin = bacteriostatic

9. What is the MOA of Foscarnet?
The PT.
Inhibits Viral DNA polymerase
proximal convoluted tubule
The PTT.

10. What is the effect of guanethidine on adrenergic NE release?
Yes
The PTT.
It inhibits release of NE.
NO AP duration effect. useful in V- tach that progresses to V- fib and in intractable SVT Last RESORT

11. Cautions When using Amiodarone?
check PFTs - LFTs - and TFTs
Staphlococcus aureus
Blocks Peptide Bond formation at the 50S subunit - Bacteriostatic
hypertension - CHF - diabetic renal disease

12. What side effect of using atropine to induce pupillary dilation would you expect?
Malaria (P. falciparum)
Methylzanthine; desired effect is bronchodilation - may cause bronchodilation by inhibiting phosphodiesterase - enzyme involved in degrading cAMP (controversial).
- Hypersensitivity reactions - Hemolysis - Nephrotoxicity (tubulointerstitial nephritis) - Kernicterus in infants Displace other drugs from albumin (e.g. - warfarin)
Atropine would also block the receptors in the ciliary muscle - causing an impairment in accommodation (cycloplegia).

13. What neurotransmitter does Amantadine affect? How does it influence this NT?
Dopamine; causes its release from intact nerve terminals
Aminoglycosides
Clavulanic acid
- Haloperidol - chlorpromazine - reserpine - MPTP

14. What is Metronidazole used for clinically?
cholestyramine - colestipol
- Phenytoin
Antiprotozoal: Giardia - Entamoeba - Trichomonas - Gardnerella vaginalis Anaerobes: Bacteroides - Clostridium
Methylzanthine; desired effect is bronchodilation - may cause bronchodilation by inhibiting phosphodiesterase - enzyme involved in degrading cAMP (controversial).

15. What is Nifurtimox administered for?

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

16. Furosemide - toxicity? (OH DANG)
not a sulfonamide - but action is the same as furosemide
vascular sm. Mus.: Nifedipine>Diltiazem>Verapamil
Epinephrine
Ototoxicity - Hypokalemia - Dehydration - Allergy (sulfa) - Nephritis (interstitial) - Gout

17. What antimuscarinic agent is used in asthma and COPD?
- Halothane - Valproic acid - acetaminophen - Amantia phalloides
Foscarnet = pyroFosphate analog
- Vitamin K & fresh frozen plasma
Ipratropium

18. How does NE modulate its own release? What other neurotransmitter has this same effect?
Pregnant women - Children; because animal studies show Damage to Cartilage
NE acts presynaptically on alpha -2 receptors to inhibit its own release. ACh also acts presynaptically through M1 receptors to inhibit NE release.
Blocks Norepi - but not Dopamine
for RSV

19. Guanethidine enhances the release of Norepi?
Inhibit steroid synthesis - used in the treatment of polycystic ovarian syndrome to prevent hirsutism.
Decreased uptake or Increased transport out of cell
Tricyclic antidepressant.
No - it inhibits the release of Nor Epi

20. What are major side effects of Methicillin - Nafcillin - and Dicloxacillin?
carbonic anhydrase inhibitors - K+ sparing diuretics
- Chloramphenicol - benzene - NSAIDS - PTU - phenytoin
dry mouth - sedation - severe rebound hypertension
Hypersensitivity reactions

21. Why is Cilastatin administered with Imipenem?
Md= (CpxCL)/F Cp= plas. Conc. CL=clear. F=bioaval.
Inhibit DNA Gyrase (topoisomerase II) - Bactericidal
hypertension - angina - arrhythmias
To inhibit renal Dihydropeptidase I and decrease Imipenem inactivation in the renal tubules

22. What is a possible result of overdose of Acetaminophen?
- Deferoxamine
Overdose produces hepatic necrosis; acetaminophen metablolite depletes glutathione and forms toxic tissue adducts in liver.
Ganciclovir is more toxic to host enzymes
for RSV

23. List the mechanism - clinical use - & toxicity of Cyclophosphamide.
Neutropenia
Ibuprofen - Naproxen - and Indomethacin
Tubocurarine - atracurium - mivacurium - pancuronium - vecuronium - rapacuronium
- Alkalating agent - NHL - Breast - ovary - & lung. - Myelosuppression - & hemorrhagic cystitis.

24. 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

25. Ca2+ channel blockers - toxicity?
cardiac depression - peripheral edema - flushing - dizziness - constipation
Atropine would also block the receptors in the ciliary muscle - causing an impairment in accommodation (cycloplegia).
cross - allergenic
carbonic anhydrase inhibitors - K+ sparing diuretics

26. Beta Blockers - CNS toxicity?
Pralidoxime regenerates active cholinesterase.
sedation - sleep alterations
1. Kidney transplantation 2. Autoimmune disorders (including glomerulonephritis and hemolytic anemia)
CMV - esp in Immunocompromised patients

27. Which drug(s) cause this reaction: Fanconi's syndrome?
Bleeding.
Gram + and Anerobes
Blood
- Tetracycline

28. What is the possible mechanism and effect of Metformin in treating diabetes?
1) Serious Gram - infections resistant to other Beta lactams 2) Meningitis (most penetrate the BBB)
- EDTA - dimercaprol - succimer - & penicillamine
Mechanism unknown; possibly inhibits gluconeogenesis and increases glycolysis; effect is to decrease serum glucose levels
Inhibition of 50S peptidyl transferase - Bacteriostatic

29. Why is carbachol and pilocarpine useful in treatment of glaucoma?
- Protamine
- Quinidine - quinine
Neomycin
They activate the ciliary muscle of the eye (open angle) and pupillary sphincter (narrow angle).

30. What are four unwanted effects of Clomiphene use?
Inhibits platelet aggregation by irreversibly inhibiting the ADP pathway involved in the binding of fibrinogen.
1. Hot flashes 2. Ovarian enlargement 3. Multiple simultaneous pregnancies 4. Visual disturbances
cardiac muscle: Verapamil>Diltiazem>Nifedipine
Tubocurarine - atracurium - mivacurium - pancuronium - vecuronium - rapacuronium

31. What is Ketoconazole specifically used for?
- Bleomycin - amiodarone - busulfan
Resistant Gram - infections
Nifedipine - Verapamil - Diltiazem
Blastomyces - Coccidioides - Histoplasma - C. albicans; Hypercortisolism

32. What is the MOA for Nystatin?
blocking the beta adrenergic receptor leads to decreased cAMP - and decreased Ca2+ flux
Small lipid - soluble molecule
Binds ergosterol - Disrupts fungal membranes
constipation - flushing - edema - CV effects (CHF - AV block - sinus node depression) - and torsade de pointes (Bepridil)

33. Name three Antiarrhythmic drugs in class IB.
- Alkalinize urine & dialysis
Gram - rods: Klebsiella species - Pseudomonas species - Serratia species
Lidocaine - Mexiletine - Tocainide
Epinephrine to treat anaphylaxis. Also useful if you have open angle glaucoma - asthma - or hypotension.

34. Which drug(s) cause this reaction: Neuro and Nephrotoxic?
Give an antichloinesterase - neostigmine - edrophonium - etc
Headache - flushing - dyspepsia - blue - green color vision.
- polymyxins
GI intolerance (nausea - diarrhea) - Hyperglycemia - Lipid abnormalities - Thrombocytopenia (Indinavir)

35. What is the memory key involving the '4 R's of Rifampin?'
1. Streptokinase 2. Urokinase 3. tPA (alteplase) - APSAC (anistreplase)
1. Aluminum hydroxide: constipation and hypophosphatemia 2. Magnesium hydroxide: diarrhea 3. Calcium carbonate: Hypercalcemia - rebound acid increase - All may cause hypokalemia
Chronic (weeks or months)
1. RNA pol inhibitor 2. Revs up P450 3. Red/orange body fluids 4. Rapid resistance if used alone

36. Resistance mechanisms for Cephalosporins/Penicillins
Acetylcholine esterase
AluMINIMUM amount of feces.
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.
Beta - lactamase cleavage of Beta - lactam ring

37. Which drug(s) cause this reaction: Thrombotic complications?
Peptic ulcer disease.
- partial agonist can have increased - decreased - /A21or equal potency as full agonist. - Potency is an independent factor.
- Oral Contraceptives
Antileukotriene; blocks leukotriene receptors.

38. What drugs target anticholinesterase
Neostigmine - pyridostigmine edrophonium - physostigmine echothiophate
- Act on same receptor - Full has greater efficacy
Sotalol - Ibutilide - Bretylium - Amiodarone
osmotic diuretic - increase tubular fluid osmolarity - thereby increasing urine flow

39. How is Leishmaniasis treated?
- Clindamycin
Methicillin - Nafcillin - and Dicloxacillin
Pentavalent Antimony
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia

40. What is the mechanism of action of Allopurinol used to treat chronic gout?
dry mouth - sedation - severe rebound hypertension
Inhibits xanthine oxidase - decresing conversion of xanthine to uric acid.
- Ethanol - dialysis - & fomepizole
Antimetabolite derivative of 6- mercaptopurine that interferes with the metablolism and synthesis of nucleic acid.

41. Which drug(s) cause this reaction: Tendonitis and rupture?
- Infections - Trauma - Seizures - CO - Overdose - Metabolic - Alcohol (IT'S COMA)
Forms toxic metabolites in the bacterial cell - Bactericidal
- Fluoroquinolones
Amphetamine and Ephedrine

42. What are the Anti - TB drugs?
WEPT: Warfarin affects the Extrinsic pathway and prolongs the PT.
CMV - esp in Immunocompromised patients
Rifampin - Ethambutol - Streptomycin - Pyrazinamide - Isoniazid (INH)
Tricyclic antidepressant.

43. How is Ganciclovir used clinically?
Chronic gout.
aPTT (intrinsic pathway)
CMV - esp in Immunocompromised patients
Activates antithrombin III

44. 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

45. Beta Blockers - BP?
Blocks Norepi - but not Dopamine
Inhibits NaCl reabsorption in the early distal tubule. Decreases Ca2+ excretion.
decrease
Succinylcholine

46. For Heparin What is the Structure
Large anionic polymer - acidic
Beta lactams - inhibit cell wall synthesis - Bactericidal
To inhibit renal Dihydropeptidase I and decrease Imipenem inactivation in the renal tubules
- Methylene blue

47. For Warfarin What is the Lab value to monitor
PT
- Quinidine - quinine
Malaria (P. falciparum)
pulmonary fibrosis - corneal deposits - hepatotoxicity - skin deposits resulting in photodermatitis - neurologic effects - consitpation - CV (bradycardia - heart block - CHF) - and hypo - or hyperthyroidism.

48. What is the mechanism of action of the H2 Blockers?
Inhibits reabsorption of uric acid.
Cell membrane Ca2+ channels of cardiac sarcomere
Reversible block of histamine H2 receptors
torsade de pointes - excessive Beta block

49. Which drug(s) cause this reaction: Torsade de pointes (2)?
1) Serious Gram - infections resistant to other Beta lactams 2) Meningitis (most penetrate the BBB)
alpha -1 > alpha -2; used as a pupil dilator - vasoconstrictor - and for nasal decongestion
- Class III antiarrhythmics (sotalol) - class IA (quinidine)
Because they require some residual islet function.

50. List the specific antidote for this toxin: Iron
- Flumazenil
Fast vs. Slow Acetylators
- Deferoxamine
Fever/Chills - Hypotension - Nephrotoxicity - Arrhythmias