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. These drugs acts indirectly by releasing strored catecholamines in the presynaptic terminal
Amphetamine and Ephedrine
Phase 1 = prolonged depolarization - no antidote - effect potentiated by anticholinesterase; Phase 2 = repolarized but blocked - an anticholinesterase is the antidote for this phase.
Cyclooxygenases (COX I - COX II).
collecting ducts

2. For Heparin What is the Treatment for overdose
- Alkalinize urine & dialysis
Protamine sulfate
1. Bleeding 2. Teratogenicity 3. Drug - drug interactions
HSV - VZV - EBV - Mucocutaneous and Genital Herpes Lesions - Prophylaxis in Immunocompromised pts

3. What is the category - desired effect - and adverse effect of Isoproterenol in the treatment of Asthma?
- B51Naloxone / naltrexone (Narcan)
Succinylcholine
Nonspecific beta - agonist; desired effect is the relaxation of bronchial smooth muscle (Beta 2). Adverse effect is tachycardia (Beta 1).
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.

4. For Warfarin What is the Duration of action
Liver
Chronic (weeks or months)
Same as penicillin. Act as narrow spectrum antibiotics
Na/K ATPase

5. Why would you use pralidoxime after exposure to an organophosphate?
Inhibits cell wall synthesis ( binds to PBP3). A monobactam
Pralidoxime regenerates active cholinesterase.
Give an antichloinesterase - neostigmine - edrophonium - etc
pulmonary edema - dehydration

6. What is the clincial use for Misoprostol?
Ipratropium
Close K+ channels in Beta - cell membrane leading to cell depolarization causing insulin release triggered by increase in Calcium ion influx.
Stimulating beta receptors stimulates heart rate - but beta receptor induced vasodilation reduces peripheral resistance.
Prevention of NSAID- induced peptic ulcers - maintains a PDA.

7. What are the phases of succinylcholine neuromuscular blockade?
Ceftriaxone
NE acts presynaptically on alpha -2 receptors to inhibit its own release. ACh also acts presynaptically through M1 receptors to inhibit NE release.
carbonic anhydrase inhibitors - K+ sparing diuretics
Phase 1 = prolonged depolarization - no antidote - effect potentiated by anticholinesterase; Phase 2 = repolarized but blocked - an anticholinesterase is the antidote for this phase.

8. List the mechanism - clinical use - & toxicity of Prednisone.

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

9. Norepi feedbacks and inhibits the presynaptic receptor by What mechanism
PT
Gram + - Gram - - Norcardia - Chlamydia
Binding to the presynaptic alpha 2 release modulating receptors
1. Pioglitazone 2. Rosiglitazone.

10. Why is reserpine effective in treating HTN?
Reserpine inhibits dopamine transport into vesicles - attenuating its conversion to NE by dopamine beta - hydroxylase.
Succinylcholine
Inhibits NaCl reabsorption in the early distal tubule. Decreases Ca2+ excretion.
Fluconazole - Ketoconazole - Clotrimazole - Miconazole - Itraconazole

11. What is a possible toxicity of Alpha - glucosidase inhibitors used in type -2 diabetes?
Rare.
- Antipsychotics
GI disturbances.
Pretreat with antihistamines and a slow infusion rate

12. Verapamil has similar action to?
Penicillin.
- Class III antiarrhythmics (sotalol) - class IA (quinidine)
Ataxia - Dizziness - Slurred speech
Beta Blockers

13. While at a tail gait party - you bite into a sandwich that a yellow jacket is also enjoying. Knowing your allergy to this creature - What should you do?
Epinephrine to treat anaphylaxis. Also useful if you have open angle glaucoma - asthma - or hypotension.
- N- acetylcystine
sedation - depression - nasal stuffiness - diarrhea
- Alkalating agent - testicular - bladder - ovary -& lung - Nephrotoxicity & CN VIII damage.

14. Which drug(s) cause this reaction: Gingival hyperplasia?
- Phenytoin
1. Better bioavailability 2. 2 to 4 times longer half life 3. Can be administered subcutaneously 4. Does not require laboratory monitoring
Mechanism unknown; possibly inhibits gluconeogenesis and increases glycolysis; effect is to decrease serum glucose levels
Inhibition of 50S peptidyl transferase - Bacteriostatic

15. Which drug(s) cause this reaction: Oto and Nephrotoxicity (3)?
Praziquantel
- ACE inhibitors (Losartan>no cough)
Pseudomonas species and Gram - rods
- aminoglycosides - loop diuretics - cisplatin

16. What is the category - desired effect - and period of use of albuterol in the treatment of Asthma?
Leukotrienes increasing bronchial tone.
Altered bacterial Dihydropteroate Synthetase - Decreased uptake - or Increased PABA synthesis
Beta 2 agonist; desired effect is the relaxation of bronchial smooth muscle (Beta 2). Use during acute exacerbation.
Because they require some residual islet function.

17. Why are albuterol and terbutaline effective in tx of acute asthmatic attacks?
GI upset - Superinfections - Skin rashes - Headache - Dizziness
Pentavalent Antimony
HTN - CHF - calcium stone formation - nephrogenic DI.
These B-2 agonists cause respiratory smooth muscle to relax.

18. If a patient is given hexamethonium - What would happen to his/her heart rate?
1. Taken daily 2. No protection against STDs 3. Raises triglycerides 4. Depression - weight gain - nausea - HTN 5. Hypercoagulable state
impotence - asthma - CV effects (bradycardia - CHF - AV block) - CNS effects (sedation - sleep alterations)
It would increase to ~ 100 beats/min. Both sympathetic and vagal stimulation would be knocked out - but the SA node has an intrinsic pace of 100 beats/min - Which is normally checked by vagal stimulation.
Gram + cocci - Haemophilus influenza - Enterobacter aerogenes - Neisseria species - P. mirabilis - E. coli - K. pneumoniae - Serratia marcescens ( HEN PEcKS )

19. What are major side effects of Methicillin - Nafcillin - and Dicloxacillin?
Mechanism unknown; possibly inhibits gluconeogenesis and increases glycolysis; effect is to decrease serum glucose levels
Hypersensitivity reactions
- Shifts the curve to the right - increases Km
G6PD deficient individuals

20. ________ ae not resistant to penicillinase - - but they are less susceptible than the other Beta lactams
- Methotrexate - 5 FU - 6 mercaptopurine
Cephalosporins
hyperkalemia - endocrine effects (gynecomastia - anti - androgen)
depresses ectopic pacemakers - especially in digoxin toxicity

21. What is the MOA for the Aminoglycosides?
1. Phospholipase A2 is prevented from releasing arachidonic acid 2. Decreases protein synthesis thus lowering amount of Cyclooxygenase enzymes
Inhibits formation of Initiation Complex - causes misreading of mRNA - Bactericidal
GI distress - Skin rash - and Seizures at high plasma levels
Well tolerated in general but occasionally - Nephrotoxicity - Ototoxicity - Thrombophlebitis - diffuse flushing='Red Man Syndrome'

22. What is the memory key for Isoniazid (INH) toxicity?
- MT polymerization inhibitor(M phase) - MOPP - lymphoma - Willm's & choriocarcinoma - neurotoxicity and myelosuppression
Inhibits NaCl reabsorption in the early distal tubule. Decreases Ca2+ excretion.
Keratin containing tissues - e.g. - nails
INH: Injures Neurons and Hepatocytes

23. How is Ribavirin used clinically?
for RSV
AZT - to reduce risk of Fetal Transmission
- Disulfram & also sulfonylureas - metronidazole
ACIDazolamide' causes acidosis

24. Mnemonic for Foscarnet?
Foscarnet = pyroFosphate analog
Dobutamine has more of an affintiy for beta -1 than beta -2 - and is used for treating heart failure and shock. Albuterol and terbutaline is the reverse - and is used in treatment of acute asthma.
Carbachol - pilocarpine - physostigmine - echothiophate
Cell membrane Ca2+ channels of cardiac sarcomere

25. List the specific antidote for this toxin: Iron
- Deferoxamine
scopolamine
- reduction - oxy - & hydrolysis - H2O sol. Polar product - P450
Hypersensitivity reactions

26. What is the mechanism of action of Allopurinol used to treat chronic gout?
Inhibits xanthine oxidase - decresing conversion of xanthine to uric acid.
Gram + and Anerobes
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
Intrathecally

27. What are three types of antacids and the problems that can result from their overuse?
1. Aluminum hydroxide: constipation and hypophosphatemia 2. Magnesium hydroxide: diarrhea 3. Calcium carbonate: Hypercalcemia - rebound acid increase - All may cause hypokalemia
It affects beta receptors equally and is used in AV heart block (rare).
constipation - flushing - edema - CV effects (CHF - AV block - sinus node depression) - and torsade de pointes (Bepridil)
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)

28. What cholinomimetic is useful in the diagnosis of Myasthenia Gravis
Edrophonium
Binds 30S subunit and prevents attachment of aminoacyl - tRNA - Bacteriostatic
Succinylcholine
- Tricyclic antidepressants

29. List the mechanism - clinical use - & toxicity of 5 FU.
- Shifts the curve down - reduces Vmax
Selectively inhibit cyclooxygenase (COX) isoform 2 - Which is found in inflammatory cells nad mediates inflammation and pain; spares COX-1 Which helps maintain the gastric mucosa.
Cardiac glycoside (inotropic agent).
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression

30. What are three possible toxicities of NSAID usage?
Megaloblastic anemia - Leukopenia - Granulocytopenia
1. Renal damage 2. Aplastic anemia 3. GI distress
- Phenytoin
proarrhythmic

31. Clinical use of Isoniazid (INH)?
Na/K ATPase
Quinolones
severe hypertension - CHF
Mycobacterium tuberculosis - the only agent used as solo prophylaxis against TB

32. What is the clinical use for Clomiphene?
Treatment of infertility.
Inhibit Ergosterol synthesis
Cestode/tapeworm (e.g. - D. latum - Taenia species Except Cysticercosis
Digoxin=urinary Digitoxin=biliary

33. What are the products and their toxicities of the metabolism of Methanol by / alcohol dehydrogenase?
Penicillin - G
severe hypertension - CHF
- Formaldehyde & formic acid - severe acidosis & retinal damage
Norepinephrine (Alpha1 -2 and beta 1)

34. What antimuscarinic drug is useful for the tx of asthma
Does not cross
Chloramphenicol - Erythromycin/macrolides - Lincomycin - Clindamycin - Streptogramins (quinupristin - dalfopristin)
Ipratropium
Anaerobic infections (e.g. - B. fragilis - C. perfringens)

35. What are the products and their toxicities of the metabolism of Ethylene Glycol by / alcohol dehydrogenase?
- Oxalic acid - Acidosis & nephrotoxicity
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia
Giardiasis - Amoebic dysentery (E. histolytica) - Bacterial vaginitis (Gardnerella vaginalis) - Trichomonas
NO AP duration effect. useful in V- tach that progresses to V- fib and in intractable SVT Last RESORT

36. The COX-2 inhibitors (celecoxib - rofecoxib) have similar side effects to the NSAIDs with What one exception?
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression
Chronic gout.
The COX-2 inhibitors should not have the corrosive effects of other NSAIDs on the gastrointestinal lining.
- Dimercaprol - succimer

37. Name two organisms Vancomycin is commonly used for?
Staphlococcus aureus and Clostridium difficile (pseudomembranous colitis)
Anaerobic infections (e.g. - B. fragilis - C. perfringens)
Flutamide is a nonsteroidal competitive inhibitor of androgens at the testosterone receptor - used in prostate carcinoma.
1. Hot flashes 2. Ovarian enlargement 3. Multiple simultaneous pregnancies 4. Visual disturbances

38. What are four clinical uses of glucocorticoids?

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

39. Where does Griseofulvin deposit?
Keratin containing tissues - e.g. - nails
Prevents the release of Ca from SR of skeletal muscle
Diarrhea
first dose orthostatic hypotension - dizziness - headache

40. What are the major toxic side effects of the Cephalosporins?
Giant Roundworm (Ascaris) - Hookworm (Necator/Ancylostoma) - Pinworm (Enterobius)
1) Hypersensitivity reactions 2) Increased nephrotoxicity of Aminoglycosides 3) Disulfiram - like reaction with ethanol (those with a methylthiotetrazole group - e.g. - cefamandole)
Acts as a wide spectrum carbapenem
Beta lactams - inhibit cell wall synthesis - Bactericidal

41. Are Ampicillin and Amoxicillin are not...
penicillinase resistant
diuretics - sympathoplegics - vasodilators - ACE inhibitors - Angiotensin II receptor inhibitors
Penicillin - G
- Tetracycline - amiodarone - sulfonamides

42. Adverse effects of Captopril?
fetal renal toxicity - hyperkalemia - Cough - Angioedema - Proteinuria - Taste changes - hypOtension - Pregnancy problems - Rash - Increased renin - Lower Angiotensin II (CAPTOPRIL)
Immediate anticoagulation for PE - stroke - angina - MI - DVT.
Initially vasoconstriction would increase bp - but then it acts on central alpha -2 receptors to decrease adrenergic outflow resulting in decreased bp.
None. No - because atropine would block the postganglionic muscarinic receptors involved in sweat gland stimulation.

43. What type of neurological blockade would hexamethonium create?
Hexamethonium is a nicotinic antagonist - and thus is a ganglionic blocker.
Digitoxin 168hrs Digoxin 40 hrs
Bleeding.
Protamine sulfate

44. Which drug(s) cause this reaction: P450 induction(6)?
Spironolactone - Triamterene - Amiloride (the K+ STAys)
- Barbiturates - phenytoin - carbamazipine - rifampin - griseofulvin - quinidine
- Estrogen receptor antagonist - Breast CA - increased endometrial CA risk
impotence - exacerbation of asthma - CV effects - CNS effects - may mask hypoclycemia

45. What drugs target anticholinesterase
Neostigmine - pyridostigmine edrophonium - physostigmine echothiophate
Parkinson patients benefit from antimuscarinic agents through its inhibitory action within the indirect pathway.
Yes
Can affect absorption - bioavailability - or urinary excretion of other drugs by altering gastric and urinary pH or by delaying gastric emptying.

46. What type of gout is treated with Allopurinol?
Due to the presence of a bulkier R group
H2 antagonist
Chronic gout.
Pregnant women - Children; because animal studies show Damage to Cartilage

47. How is Chloramphenical used clinically?
hypokalemia - slight hyperlipidemia - hyperuricemia - lassitude - hypercalcemia - hyperglycemia
1. Hypoglycemia (more common with 2nd - generation drugs: glyburide - glipizide) 2. Disulfiram - like effects (not seen with 2nd - generation drugs).
Flutamide is a nonsteroidal competitive inhibitor of androgens at the testosterone receptor - used in prostate carcinoma.
Meningitis (H. influenza - N. meningitidis - S. pneumoniae) - Conserative treatment due to toxicities

48. What are two toxicities of the Sulfonylureas?
Recurrent UTIs - Shigella - Salmonella - Pneumocystis carinii pneumonia
When pts have Low CD4+ (< 500 cells/cubic mm) or a High Viral Load
propanolol - esmolol - metoprolol - atenolol - timolol
1. Hypoglycemia (more common with 2nd - generation drugs: glyburide - glipizide) 2. Disulfiram - like effects (not seen with 2nd - generation drugs).

49. Adverse effects of Prazosin?
first dose orthostatic hypotension - dizziness - headache
Gram + and Anerobes
1. Phospholipase A2 is prevented from releasing arachidonic acid 2. Decreases protein synthesis thus lowering amount of Cyclooxygenase enzymes
osmotic diuretic - increase tubular fluid osmolarity - thereby increasing urine flow

50. List the specific antidote for this toxin: Anticholinesterases (organophosphate.)
Prevents release of mediators from mast cells. Effective only for the prophylaxis of asthma. Not effective during an acute attack.
- Atropine & pralidoxime
They activate the ciliary muscle of the eye (open angle) and pupillary sphincter (narrow angle).
Mg = Must go to the bathroom.