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 diuretics increase urine Ca2+?
Pyridoxine (B6) administration
Carbachol - pilocarpine - physostigmine - echothiophate
loop diuretics - spironolactone
Nevirapine - Delavirdine

2. What is the clinical use for Clomiphene?
Inhibits organification and coupling of thyroid hormone synthesis. Also decreases peripheral conversion of T4 to T3.
Treatment of infertility.
Blocks Influenza A and RubellA; causes problems with the cerebellA
- S- phase anti - metabolite Pyr analogue - Colon - solid tumors - & BCC/ - Irreversible myelosuppression

3. What cholinomimetics might your pt be taking for his glaucoma
Carbachol - pilocarpine - physostigmine - echothiophate
Competitive inibitor of progestins at progesterone receptors.
Norepinephrine
1. Antipyretic 2. Analgesic 3. Anti - inflammatory 4. Antiplatelet drug.

4. Name some common Sulfonamides (4)
Clavulanic acid
Sulfamethoxazole (SMZ) - Sulfisoxazole - Triple sulfas - Sulfadiazine
- Steroids - Tamoxifen
Ciprofloxacin - Norfloxacin - Ofloxacin - Grepafloxacin - Enoxacin - Nalidixic acid

5. Dobutamine used for the tx of shock acts on Which receptors
- Tetracycline - amiodarone - sulfonamides
Altered bacterial Dihydropteroate Synthetase - Decreased uptake - or Increased PABA synthesis
Mebendazole/Thiabendazole - Pyrantel Pamoate
Beta1 more than B2

6. A 57 yo heart failure pt develops cardiac decompensation - What drug will give you adequate perfusion of his kidneys as well as tx for his Hypotension
not a sulfonamide - but action is the same as furosemide
Dopamine
- Isoniazid
Short.

7. What side effect of using atropine to induce pupillary dilation would you expect?
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
1. Suppresses organ rejection after transplantation 2. Selected autoimmune disorders.
Atropine would also block the receptors in the ciliary muscle - causing an impairment in accommodation (cycloplegia).
Penicillin.

8. Can Heparin be used during pregnancy?
Yes - it does not cross the placenta.
pulmonary edema - dehydration
Anaerobes
- Alkalinize urine & dialysis

9. List the mechanism - clinical use - & toxicity of Bleomycin.
- DNA intercalator - testicular & lymphomas - Pulmonary fibrosis mild myelosuppression.
edrophonium (extremely short acting anticholinesterase)
No - it inhibits the release of Nor Epi
Nifedipine - Verapamil - Diltiazem

10. Which drug(s) cause this reaction: Neuro and Nephrotoxic?
severe orthostatic hypotension - blurred vision - constipation - sexual dysfunction
- polymyxins
Liver
is resistant

11. Furosemide - class and mechanism?
Inhibits DNA dependent RNA polymerase
Zidovudine (AZT) - Didanosine (ddI) - Zalcitabine (ddC) - Stavudine (d4T) - Lamivudine (3TC)
pulmonary edema - dehydration
Sulfonamide Loop Diuretic. Inhibits ion co - transport system of thick ascending loop. Abolishes hypertonicity of the medulla - thereby preventing concentration of the urine.

12. What is the MOA for Ampicillin and Amoxicillin?
Same as penicillin. Extended spectrum antibiotics
Scopolamine
Binding to the presynaptic alpha 2 release modulating receptors
hypertrichosis - pericardial effusion - reflex tachycardia - angina - salt retention

13. What are common serious side effects of Aminoglycosides and What are these associated with?
1) Hypersensitivity reactions 2) Increased nephrotoxicity of Aminoglycosides 3) Disulfiram - like reaction with ethanol (those with a methylthiotetrazole group - e.g. - cefamandole)
WEPT: Warfarin affects the Extrinsic pathway and prolongs the PT.
TCA
Nephrotoxicity (esp. with Cephalosporins) - Ototoxicity (esp. with Loop Diuretics)

14. Which drug(s) cause this reaction: P450 inhibition(6)?
cortical collecting tubule
It inhibits release of NE.
- Cimetidine - ketoconazole - grapefruit juice - erythromycin - INH - sulfonamides
1. Tolbutamide 2. Chlorpropamide 3. Glyburide 4. Glipizide

15. How is Trimethoprim used clinically?
Pentamidine
pulmonary edema - dehydration
Used in combination therapy with SMZ to sequentially block folate synthesis
narcolepsy - obesity - and attention deficit disorder (I wouldn't recommend this)

16. What is the category of drug names ending in - ane (e.g. Halothane)
impotence - exacerbation of asthma - CV effects - CNS effects - may mask hypoclycemia
Inhibit steroid synthesis - used in the treatment of polycystic ovarian syndrome to prevent hirsutism.
Inhalational general anesthetic.
acts at the proximal convoluted tubule to inhibit carbonic anhydrase. Causes self - limited sodium bicarb diuresis and reduction of total body bicarb stores.

17. These drugs acts indirectly by releasing strored catecholamines in the presynaptic terminal
1. Bleeding 2. Thrombocytopenia 3. Drug - drug interactions
Give an antichloinesterase - neostigmine - edrophonium - etc
Amphetamine and Ephedrine
cinchonism: HA - tinnitus - thrombocytopenia - torsade de pointes due to increased QT interval

18. Which drug(s) cause this reaction: Tubulointerstitial Nephritis (5)?
Succinylcholine
- Sulfonamides - furosemide - methicillin - rifampin - NSAIDS (ex. ASA)
Bleeding.
Cilastatin

19. Mg+- clinical use?
Blocks translocation - binds to the 23S rRNA of the 50S subunit - Bacteriostatic
Those patients who are taking nitrates.
effective in torsade de pointes and digoxin toxicity
Binds ergosterol - Disrupts fungal membranes

20. What are the side effects of Rifampin?
Penicillin - Ampicillin - Ticarcillin - Pipercillin - Imipenem - Aztreonam - Cephalosporins
Minor hepatotoxicity - Drug interactions (activates P450)
Inhibits CMV DNA polymerase
Acute (hours)

21. Which drug(s) cause this reaction: Tardive dyskinesia?
Long.
- Antipsychotics
1. Skin rash 2. Agranulocytosis (rare) 3. Aplastic anemia
Carbachol - pilocarpine - physostigmine - echothiophate

22. What is the category of drug names ending in - triptyline (e.g. Amitriptyline)
- Alkalate DNA - Brain tumors - CNS toxicity
Tricyclic antidepressant.
first dose orthostatic hypotension - dizziness - headache
Scopolamine

23. What is the MOA for Acyclovir?
Inhibit viral DNA polymerase
CMV - esp in Immunocompromised patients
Bind cell membrane - disrupt osmotic properties - Are Cationc - Basic and act as detergents
fetal renal toxicity - hyperkalemia - Cough - Angioedema - Proteinuria - Taste changes - hypOtension - Pregnancy problems - Rash - Increased renin - Lower Angiotensin II (CAPTOPRIL)

24. What is an additional side effect of Methicillin?
Interstitial nephritis
Post - op and neurogenic ileus and urinary retention - myasthenia gravis - and reversal of neuromuscular junction blockade (post - op) through anticholinesterase activity.
Inhibition of 50S peptidyl transferase - Bacteriostatic
post MI and digitalis induced arrhythmias

25. What conditions would you use dantrolene?
Interstitial nephritis
In treatment of malignant hyperthermia - due to concomitant use of halothane and succinylcholine. Also in neuroleptic malignant syndrome - a toxicity of antipsychotic drugs.
YES
hypertension - angina - arrhythmias

26. Name three K+ sparing diuretics?
Binds Ergosterol - forms Membrane Pores that Disrupt Homeostatis
Spironolactone - Triamterene - Amiloride (the K+ STAys)
Inhibits formation of Initiation Complex - causes misreading of mRNA - Bactericidal
- Upper respiratory tract infections - pneumonias - STDs: Gram+ cocci (streptococcal infect in pts allergic to penicillin) - Mycoplasma - Legionella - Chlamydia - Neisseria

27. How do you calculate maintenance dose?
Pseudomonas species and Gram - rods
Md= (CpxCL)/F Cp= plas. Conc. CL=clear. F=bioaval.
hypertrichosis - pericardial effusion - reflex tachycardia - angina - salt retention
Due to the presence of a bulkier R group

28. For Warfarin What is the Site of action
Liver
- Glucocorticoid withdrawal
Prevents the release of ACh - Which results in muscle paralysis.
GI discomfort - Acute cholestatic hepatitis - Eosinophilia - Skin rashes

29. For Warfarin What is the Lab value to monitor
Non - Nucleosides
Does not cross
PT
Leukopenia - Neutropenia - Thrombocytopenia - Renal toxicity

30. What are two types of drugs that interfere with the action of Sucralfate and why?
1) Serious Gram - infections resistant to other Beta lactams 2) Meningitis (most penetrate the BBB)
Epinephirine(Alpha1 -2 and Beta 1 -2)
Choline acetyltransferase
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.

31. Quinidine - toxicity?
carbonic anhydrase inhibitors - K+ sparing diuretics
Inhibits Viral DNA polymerase
cinchonism: HA - tinnitus - thrombocytopenia - torsade de pointes due to increased QT interval
Inhibits NaCl reabsorption in the early distal tubule. Decreases Ca2+ excretion.

32. What is the mechanism of Azathioprine?
Acetylcholine esterase
- Metronidazole - certain cephalosporins - procarbazine - sulfonylureas
Antimetabolite derivative of 6- mercaptopurine that interferes with the metablolism and synthesis of nucleic acid.
Stimulating beta receptors stimulates heart rate - but beta receptor induced vasodilation reduces peripheral resistance.

33. Which drug(s) cause this reaction: P450 induction(6)?
Acetylcholinesterase; ACh is broken down into choline and acetate.
- Barbiturates - phenytoin - carbamazipine - rifampin - griseofulvin - quinidine
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.
- Hydralazine - Procainamide - INH - phenytoin

34. What reversal agent could a Anes give to reverse the effects of Atropine
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.
RESPIre
Penicillin - G
Bethanechol - Neostigmine - physostigmine

35. For Warfarin What is the Mechanism of action
Cell membrane Ca2+ channels of cardiac sarcomere
Megaloblastic anemia - Leukopenia - Granulocytopenia
Impairs the synthesis of vitamin K- dependent clotting factors
- Chlorpromazine - thioridazine - haloperidol

36. What additional side effects exist for Ampicillin?
Rash - Pseudomembranous colitis
Non - Nucleosides
Sulfonamide Loop Diuretic. Inhibits ion co - transport system of thick ascending loop. Abolishes hypertonicity of the medulla - thereby preventing concentration of the urine.
Indirect agonist - uptake inhibitor

37. ___________ are Teratogenic
- Alkalating agents+cisplatin - Doxorubicin+Dactinomycin - Bleomycin - Etoposide
Gentamicin - Neomycin - Amikacin - Tobramycin - Streptomycin
Aminoglycosides
Prevents the release of ACh - Which results in muscle paralysis.

38. Which of the following would atropine administration cause? Hypothermia - bradycardia - excess salivation - dry flushed skin - or diarrhea
- Methylene blue
Dry flushed skin - due to inhibition of sympathetic post - ganglionic blockade on muscarinic receptors of sweat glands. All others are opposite of What would be expected.
Primaquine
Beta antagonist.

39. MOA of Succinylcholine
Theoretically it could be used to block the cephalic phase of acid secretion (vagal stimulation).
Prevents the release of Ca from SR of skeletal muscle
Binds ergosterol - Disrupts fungal membranes
reversible SLE- like syndrome

40. What is the category - desired effect - and adverse effect of Isoproterenol in the treatment of Asthma?
- Triggers apoptosis - CLL - Hodgkin's in MOPP - Cushing - like syndrome
severe orthostatic hypotension - blurred vision - constipation - sexual dysfunction
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia
Nonspecific beta - agonist; desired effect is the relaxation of bronchial smooth muscle (Beta 2). Adverse effect is tachycardia (Beta 1).

41. What are four H2 Blockers?
Digitoxin 168hrs Digoxin 40 hrs
Only in limited amounts
1. Cimetadine 2. Ranitidine 3. Famotidine 4. Nizatidine
- A57Blue lines in gingiva & long bones - Encephalopathy & Foot drop - Abdominal colic / - Sideroblastic anemia

42. What is the major side effect for Ampicillin and Amoxicillin?
- Triggers apoptosis - CLL - Hodgkin's in MOPP - Cushing - like syndrome
cortical collecting tubule
Bacitracin - Vancomycin
Hypersensitivity reactions

43. Adverse effects of beta - blockers?
Atropine pts are suffering from Cholinestrase inhibitor poisining (Nerve gas/Organophosphate poisining)
GI discomfort - Acute cholestatic hepatitis - Eosinophilia - Skin rashes
acts at the proximal convoluted tubule to inhibit carbonic anhydrase. Causes self - limited sodium bicarb diuresis and reduction of total body bicarb stores.
impotence - asthma - CV effects (bradycardia - CHF - AV block) - CNS effects (sedation - sleep alterations)

44. What is the mecanism of action - effective period - and ineffective period of use for Cromolyn in treating Asthma?
Sucralfate cannot work in the presence of antacids or H2 blockers because it requires an acidic environment to polymerize.
Prevents release of mediators from mast cells. Effective only for the prophylaxis of asthma. Not effective during an acute attack.
VACUUM your Bed Room'
Chronic gout.

45. Ibutilide - toxicity?
NE acts presynaptically on alpha -2 receptors to inhibit its own release. ACh also acts presynaptically through M1 receptors to inhibit NE release.
- Methylene blue
torsade de pointes
Cell membrane Ca2+ channels of cardiac sarcomere

46. What antimuscarinic agent is used in asthma and COPD?
Prevents release of mediators from mast cells. Effective only for the prophylaxis of asthma. Not effective during an acute attack.
Imipenem
Ipratropium
Pituitary hormone.

47. What is the category - desired effect - and possible mechanism of Theophylline in treating Asthma?
Methylzanthine; desired effect is bronchodilation - may cause bronchodilation by inhibiting phosphodiesterase - enzyme involved in degrading cAMP (controversial).
Yes - it does not cross the placenta.
loop diuretics - spironolactone
Dopamine

48. What type of gout is treated with Allopurinol?
Bacitracin - Vancomycin
Chronic gout.
Ataxia - Dizziness - Slurred speech
Bactericidal for: Gram + rod and cocci - Gram - cocci - and Spirochetes

49. What is the category of drug names ending in - caine (e.g. Lidocaine)
Methylzanthine; desired effect is bronchodilation - may cause bronchodilation by inhibiting phosphodiesterase - enzyme involved in degrading cAMP (controversial).
Beta 2 agonist; used as a long - acting agent for prophylaxis. Adverse effects are tremor and arrhythmia.
Reversibly inhibits cyclooxygenase - mostly in CNS. Inactivated peripherally.
Local anesthetic.

50. What is the mechanism of action of Heparin?
Vibrio cholerae Acne Chlamydia Ureaplasma Urealyticum Mycoplasma pneumoniae Borrelia burgdorferi (Lyme's) Rickettsia Tularemia
- Atropine & pralidoxime
Heparin catalyzes the activation of antithrombin III.
1. Mycobacterium tuberculosis 2. Delays resistance to Dapsone When used of Leprosy 3. Used in combination with other drugs