Tufts Pharm

Card Set Information

Tufts Pharm
2015-04-16 14:58:33

Tufts Pharm
Show Answers:

  1. esters
    • procaine, tetracaine, cocaine
    • Plasma
  2. LA SE
    • high systemic levels of local anesthetics in
    • general (cardiovascular collapse due to myocardial depression hypotensive shock)
  3. Prilocaine SE
  4. LA MOA
    prevent the generation of nerve impulses by interfering with sodium transport into the neuron
  5. LA absorbtion
    • non-ionized (or free base form) form can
    • penetrate tissue membranes.
    • Inflamed tissue has a lower than normal pH, which decreases the amount of non-ionized form available
    • to penetrate.
  6. how many mg of lidocaine in 1.8 ml of a 2% lidocaine solution?
    2% lidocaine is 20gm/100 ml or 20 mg/1 ml, so 36 in 1.8 ml.
  7. significant determinants of the duration
    • of conduction block with amide-type local anesthetics
    • a. pH of tissues in the area of injection
    • b. Degree of vasodilatation caused by the local anesthetic
    • d. Blood flow through the area of conduction block
    • e. Concentration of the injected anesthetic solution
  8. local anesthetics duration of action:
    • short: procaine;
    • moderate: prilocaine, mepivacaine, lidocaine;
    • long: bupivacaine, tetracaine, etidocain
  9. Propranolol interacts with lidocaine in two ways.
    • By slowing down the heart via beta receptor blockade, blood delivery (and lidocaine) to the liver is reduced, thus lidocaine remains in the systemic circulation longer, and can potentially accumulate to toxic levels.
    • Propranolol and lidocaine also compete for the same enzyme in the liver, thus metabolism of lidocaine can be reduced.
  10. High plasma LA SE
    • Initially LAs inhibit central inhibitory neurons, which results in CNS stimulation, which can proceed to convulsions.
    • At higher doses, they inhibit both inhibitory and excitatory neurons, leading to a generalized state of CNS depression which can result in respiratory depression and death.
  11. Which disease condition would make the patient most sensitive to the
    epinephrine in the local anesthetic?
    a. Grave’s disease
    b. Diabetes
    c. HIV
    d. Alcoholism
    e. Schizophrenia
    (a) Grave’s disease is an autoimmune disease that causes hyperthyroidism – the resulting high levels of circulating thyroid hormone result in a hypermetabolic state with heightened sympathetic activity, which combined with injected epinephrine could result in a hypertensive crisis.
  12. Cardiovascular collapse elicited by a high circulating dose of a local
    anesthetic may be caused by
    a. Syncope
    b. Vagal stimulation
    c. Histamine release
    d. Myocardial depression
    e. Medullary stimulation
    • (d) Cardiovascular collapse is due to a direct action of the local
    • anesthetic on the heart muscle itself (LA's in toxic doses
    • depress membrane excitability and conduction velocity), thus
    • (d) is the correct answer. All of the other alternatives are indirect
    • ways to affect the heart.
  13. most serious consequence of systemic local anesthetic toxicity is
    e. Postconvulsive central nervous system depression
  14. Local anesthetics block nerve conduction by
    e. Preventing an increase in membrane permeability to Na+
  15. Cardiovascular collapse elicited by a high circulating dose of a local
    • anesthetic may be caused by
    • d. Myocardial depression
    • (d) Cardiovascular collapse is due to a direct action of the local
    • anesthetic on the heart muscle itself (LA's in toxic doses
    • depress membrane excitability and conduction velocity), thus
    • (d) is the correct answer.
  16. 22. The most serious consequence of systemic local anesthetic toxicity is
    • e. Postconvulsive central nervous system depression
    • (e) Of the options listed, this is the one that will kill the patient,
    • which I guess makes it the most serious.
  17. 23. Hypotensive shock may result from excessive blood levels of each of the following local anesthetics EXCEPT
    • a. Cocaine
    • (a) All the listed local anesthetics except cocaine are vasodilators, especially ester-ctype drugs such as proccaine
    • and the amide lidocaine. Cocaine is the only local anesthetic that predictably produces vasoconstriction. Cocaine is also the
    • only local anesthetic to block the reuptake of NE into adrenergic neurons, and thus potentiate the NE that has been released
    • from nerve endings
  18. 25. Local anesthetics block nerve conduction by
    Preventing an increase in membrane permeability to Na+
  19. Local anesthetic agents prevent the generation of nerve impulses by
    Decreasing inward movement of sodium ion
  20. If the pH of an area is lower than normal body pH, the membrane theory of local anesthetic action predicts that the local anesthetic
    • activity would be
    • Less, owing to a decrease in the free-base form of the drug
  21. A local anesthetic injected into an inflamed area will NOT give maximum effects because
    The pH of inflamed tissue inhibits the release of the free base
  22. Penetration of a local anesthetic into nervous tissue is a function of the
    Lipid solubility of the unionized form
  23. LA onset
    • a. The greater the drug concentration, the faster the onset and the
    • greater the degree of effect
    • b. Local anesthetics block only myelinated nerve fibers at the nodes
    • of Ranvier
    • c. The smaller the diameter of the nerve fiber, the faster the onset of
    • effect
    • d. The faster the penetrance of the drug, the faster the onset of
    • effect
  24. 36. Three ml of a local anesthetic solution consisting of 2% lidocaine with 1:100,000 epinephrine contains how many milligrams of each?
    • (d) 2% lidocaine = 20 mg/ml x 3 = 60 mg lidocaine
    • 1:100,000 epi = 0.01 mg/ml x 3 = 0.03 mg epi
  25. 38. A recently introduced local anesthetic agent is claimed by the manufacturer to be several times as potent as procaine. The product
    • is available in 0.05% buffered aqueous solution in 1.8 ml. cartridge. The maximum amount recommended for dental anesthesia over a 4-
    • hour period is 30 mg. The amount is contained in approximately how many cartridges?
    • 0.05% = 0.5 mg/ml .
    • To give 30 mg, you have to give 30mg/0.5 mg/ml or 60 ml. 1 cartridge = 1.8 ml, thus 60ml /1.8ml
    • = 33.3 cartridges.
    • - first express the percentage of solution as a fraction of 100, then add the units gm/ml.
    • 0.05% equals 0.5 or 1/2 gms per 100 ml.
    • The cartridge is 1.8 ml which you can round off to almost 2 mls total.
    • In this 2 ml you would have 1 gm of the local anesthetic. You need to give 30 gms, which would
    • require 30 cartridges.
  26. 39. According to AHA guidelines, the maximum # of carpules of local anesthetic containing 1:200,000 epinephrine that can be used
    • in the patient with cardiovascular disease is
    • 4
    • the AHA limit is 0.04 mg, compared to 0.2 mg in the healthy patient. 1:200,000 equals 0.005 mg/ml or 0.009 per 1.8 ml
    • carpule. 4 carpules would thus contain 0.036 mg, which is just below the 0.04 mg limit
  27. penicillin G
    • more sensitive to acid degradation and thus is usually injected rather than taken
    • orally
  28. Which penicillin has the best gram-negative spectrum:
  29. Which drugs from a list are or are not cross-allergenic with penicillin:
    most usually asked about ones are: cephalosporins and ampicillin are, erythromycin isn't
  30. Which penicillin is useful against penicillinase-producing bugs such as staphylococcus:
  31. Which is specific for Pseudomonas infections
    extended spectrum:carbenicillin
  32. Bactericidal penicillin MOA
    kill rapidity growing cells by inhibiting cell wall synthesis
  33. tetracycline MOA
    • Static, limit population growth, but do not kill bugs by interfering with protein synthesis
    • on bacterial ribosomes
  34. nystatin MOA
    bindergosterol in fungal cell walls to weaken the wall
  35. Sulfonamides MOA
    compete with PABA in folic acid synthesis, thus resulting in folic acid deficiency
  36. What are symptoms seen during allergic reactions to penicillins:
    dermatitis, stomatitis, bronchoconstriction and cardiovascular collapse
  37. What agent produces GI upset and pseudomonas colitis:
  38. Which agents are most likely or least likely to cause superinfection:
    • most: broad spectrum agents such as tetracyclines;
    • least: narrow spectrum agents such as penicillin G
  39. Aplastic anemia is associated with which AB?
  40. Liver damage or hepatotoxicity is associated with which AB?
  41. Erythromycin estolate associated with
    allergic cholestatic hepatitis
  42. ____ cancel each other out due to opposing mechanisms of action
    Tetracycline and penicillin (cidal-static interaction)
  43. ____alters the rate of renal clearance of penicillin
  44. Effectiveness of tetracyclines is reduced by concurrent ingestion of
    antacids or dairy products
  45. Broad spectrum antibiotics enhance the action of
    coumarin anticoagulants because of the reduction of Vitamin K sources
  46. Antibiotics such as ampicillin decrease the effectiveness of oral contraceptives
    due to suppression of normal Gl flora involved in the recycling of active steroids from bile conjugates, leading to more rapid excretion of the steroids from the body
  47. Macrolides such as erythromycin inhibit the metabolism of drugs such
    seldane, digoxin, etc.
  48. Acyclovir:
    an antiviral used for various forms of herpes
  49. Fluconazole or ketoconazole:
    systemic-acting antifungals useful for treating candidiasis
  50. 8 The principal difference among potassium, procaine and benzathine
    • salts of penicillin G is their
    • c. Duration of action
    • most cases you are going to use Pen VK orally,
  51. Which of the following antibiotics may be cross-allergenic with penicillin?
    a. Neomycin
    b. Cephalexin
    c. Clindamycin
    d. Erythromycin
    e. All of the above
    • (b) This is a memorization question, with (b) the correct answer. You have to remember that the cephalosporins (like
    • cephalexin) are chemically related to the penicillins. The others are not chemically related and thus cross-allergenicity is unlikely
  52. Which of the following antibiotics shows an incidence of approximately 8% cross-allergenicity with penicillins?
    b. cephalexin
  53. 14. Which of the following groups of antibiotics is related both structurally and by mode of action to the penicillins?
    c. Cephalosporins
  54. 13. For the dentist, the most reliable method of detecting a patient's allergy to penicillin is by
    b. Taking a thorough medical history
  55. 14. Which of the following antibiotics is the substitute of choice for penicillin in the penicillin-sensitive patient?
    • b. Erythromycin
    • the spectrum of activity of erthromycin is very similar to penicillin.
    • Standards have now changed such that clindamycin is the drug of choice in this situation.
  56. 16. Which of the following penicillins has a broader gram-negative
    • spectrum than penicillin G?
    • b. Ampicillin “extended-spectrum” form of penicillin
  57. Which of the following antibiotics should be considered the drug of choice in the treatment of infection caused by a penicillinaseproducing
    • staphylococcus?
    • e. Dicloxacillin
    • Ampicillin is an extended spectrum penicillin, and is not penicillinase resistant.
    • Erythromycin shouldn’t be affected by penicillinases, since it isn’t a peniciilin, but it doesn’t work against staph for other reasons.
  58. Which of the following is a bactericidal antibiotic used specifically inthe treatment of infections caused by Pseudomonas species and
    • indole-positive Proteus species?
    • e. Carbenicillin
  59. Chlortetracycline acts by interfering with
    Protein synthesis on bacterial but not mammalian ribosomes
  60. The probable mechanism of the bacteriostatic action of sulfonamides involves
    Competition with para-aminobenzoic acid in folic acid synthesis
  61. Which antibiotic is able to achieve a higher concentration in bone than in serum?
    • clindamycin
    • useful for treating bone infections such as osteomyelitis.
    • The question might have substituted gingival fluid for bone – that would make the answer tetracycline
  62. Tetracycline reduces the effectiveness of concomitantly administered penicillin by
    • (e) tetracycline is bacteriostatic and would slow the rapid growth of the microbial population that a bactericidal drug such
    • as penicillin needs to be effective, sine only when rapidly dividing are the cells making cell walls
  63. Which of the following antibiotics is most likely to cause liver damage?
    • c. Tetracycline
    • Tetracyclines have been shown to be hepatotoxic following high doses in pregnant patients with a history of renal disease.
  64. ____ can damage the eighth nerve, affecting both balance and hearing
  65. amphotericin B
    antifungal agent that produces such adverse side effects as nephrotoxicity and hypokalemia, but not liver toxicity.
  66. Which of the following erythromycins associated with an allergic cholestatic hepatitis?
    A. Erythromycin base
    B. Erythromycin stearate
    C. Erythromycin estolate
    D. Erythromycin succinate
    C. Erythromycin estolate
    (this multiple choice question has been scrambled)
  67. Gastrointestinal upset and pseudomembranous colitis has been prominently associated with
    c. Clindamycin
  68. Symptoms that may be characterized as allergic manifestations during penicillin therapy are
    d. Dermatitis, stomatitis, bronchoconstriction and cardiovascular collapse
  69. Aplastic anemia is a serious toxic effect that occurs particularly after a course of treatment with which of the following antibiotics?
    e. Chloramphenicol
  70. Each of the following is a side effect of prolonged tetracycline hydrochloride therapy EXCEPT:
    • a. Suprainfection
    • b. Photosensitivity
    • d. Discoloration of newly forming teeth
    • e. Gastrointestinal symptoms (when administered orally)
  71. Colitis that results following clindamycin therapy is caused by an overgrowth of
    a. C. dificile
  72. 37. Which antibiotic is appropriate for premedication in the penicillin allergic patient?
    b. Clindamycin
  73. 39. Which of the following has the broadest antimicrobial spectrum?
    a. Vancomycin (Vancocin )
    b. Clindamycin (Cleocin )
    c. Erythromycin (Erythrocin )
    d. Chlortetracycline (Aureomycin )
    e. A third generation cephalosporin
    • (d) Answer is (d)- remember, tetracyclines are broad spectrum antibiotics effective against both gram-negative and grampositive
    • cocci and bacilli.
    • Clindamycin has a spectrum of activity similar to erthyromycin and vancomycin, which is less than that of the tetracylines, mainly affecting gram-positive
    • microorganisms. Ist generation cephalosporins are effective against both gram-negative and gram-positive organisms, but the third generation ones have increased activity against gramnegative
    • but greatly decreased activity against gram-positive microorganisms.
  74. Sulfonamides and trimethoprim are synergistic bacteriostatic agents because in bacteria they
    b. Interfere sequentially with folinic acid production
  75. The concurrent administration of penicillin G and probenecid results in
    • c. Decreased renal excretion of penicillin G
    • penicillin is metabolized in the liver, but it rapidly disappears from the blood due to rapid clearance by the
    • kidneys. 90% is excreted by tubular secretion.
    • Thus patients with renal disease will show high blood levels of penicillin.
    • Similarly, probenicid, a uricosuric agent (a drug which tends to enhance the excretion of uric acid by reducing renal tubular
    • transport mechanisms), reduces the renal clearance of penicillins. And you wondered why we had those lectures on
    • pharmacokinetics!
  76. When broad-spectrum antibiotics are administered with coumarin anticoagulants, the anticoagulant action may be
    Increased because of reduction of vitamin K sources
  77. Erythromycin should be avoided in the patient taking
    • b. Seldane
    • (b) remember the famous erythromycin –Seldane potentially lethal interaction, whereby erythromycin blocks the metabolism
    • of Seldane to its antihistamine metabolite – it stays unmetabolized and causes cardiac arrthymias. Of course this
    • question could have many other options listed, since erythromycin decreases the metabolism of so many other useful drugs, such as digoxin.
  78. hypertension tx:
    • 1) Diuretics such as the high ceiling or loop-acting diuretic, furosemide;
    • 2) Beta-blockers such as propranolol or the cardioselective beta blocker metoprololor atenolol
    • 3) Alpha-1 blockers such as prazosin,
    • 4) Centrally acting adrenergic drugs such as methyldopa or clonidine
    • 5) Neuronal blockers such as guanethidine (reserved for severe hypertension)
    • 6) Angiotensin converting enzyme inhibitors such as Captopril, lisinopril
  79. angina tx:
    Nitroglycerin, sometimes propranolol, calcium channel blockers such as verapamil
  80. arrhythmias tx:
    • 1) Lidocaine (ventricular arrhythmias),
    • 2) Phenytoin (to reverse digitalis induced arrhythmias),
    • 3) Quinidine (supraventricular tachyarrhythmias, atrial fibrillation),
    • 4) Verapamil (supraventricular tachyarrhythmias,paroxysmal tachycardia, atrial fibrillation),
    • 5) Digitalis (atrial fibrillation, paroxysmal tachycardia)
    • 6) Propranolol (paroxysmal tachycardia)
  81. Congestive heart failure tx:
    Glycosides such as digitalis, digoxin, ACE inhibitors such as captopril
  82. Antiarrhythmics Type 1A agents such as quinidine MOA:
    increasing the refractory period of cardiac muscle
  83. Antiarrhythmics Type 1B agents such as lidocaine MOA:
    decrease cardiac excitability
  84. When digitalis is used for atrial fibrillation it acts by
    decreasing the rate of A-V conduction
  85. Antiangina drugs MOA:
    • problem is insufficient oxygen to meet demands of myocardium
    • a. Nitroglycerin increases oxygen supply to the heart by a direct vasodilatory action on the smooth muscle in coronary arteries
    • b. Propranolol reduces oxygen demand by preventing chronotropic responses to endogenous epinephrine, emotions and exercise.
    • c. Calcium channel blockers decrease oxygen demand by reducing afterload by reducing peripheral resistance via
    • vasodilation
  86. Antihypertensives MOA:
    • Remember, most drugs have the ultimate effect of reducing peripheral resistance via vasodilation
    • ACE inhibitors: Captopril blocks the enzyme which converts angiotensin I to angiotensin II.
    • The latter is a potent vasoconstrictor (administration of angiotensin will result in an elevation of blood pressure).
  87. Adrenergic Agents MOA:
    • a. Prazosin: selective alpa-1 blocker, inhibits binding of nerve induced release of NE resulting in vasodilation
    • b. Methyldopa: acts centrally as a false neurotransmitter stimulating alpha receptors to reduce sympathetic outflow
    • resulting in vasodilation
    • c. Clonidine: selective agonist stimulates alpha-2receptors in the CNS to reduce sympathetic outflow to peripheral vessels
    • resulting in vasodilation
    • d. Propranolol: nonselective beta blocker reduces cardiac output and inhibits renin secretion
    • e. Metoprolol: selective beta-1 blocker, reduces cardiac output
  88. Diuretics MOA:
    • decrease the renal absorption of sodium, thus resulting in fluid loss and a reduction in blood volume. This decreases
    • the work the heart has to pump. Also have weak dilatory action. Types of diuretics which may be mentioned include:
    • a. Thiazides: chlorothiazide
    • b. High-ceiling or loop acting: furosemide
    • c. Potassium sparing: spironolactone
  89. Congestive heart failure drugs MOA:
    • a. Cardiac glycosides such as digitalis or digitoxin are effective because they have a positive inotropic effect, increasing the force of contraction of the myocardium. This is
    • achieved by an inhibition of Na+, K+ ATPASE leading to increased calcium influx.
    • Digitalis therapy reduces the compensatory changes that are associated with congestive heart failure such as increased heart size, rate, edema, etc.
  90. 1. Quinidine is principally used to treat
    • d. Supraventricular tachyarrhythmias, Ventricular fibrillation
    • It reduces automaticity and responsiveness and increases refractoriness.
    • It also has an antimuscarinic action preventing the bradycardia that follows vagal stimulation.
  91. Verapamil is most efficacious in the treatment of
    Atrial fibrillation
  92. Digitalis is useful in the treatment of which of the following conditions?
    • a. Atrial fibrillation
    • b. Congestive heart failure
    • c. Paroxysmal atrial tachycardia
    • d. All of the above
    • D
  93. The drug of choice for initial therapy for mild hypertension is
    d. Chlorothiazide
  94. Which of the following antihypertensives are usually reserved for treatment of severe hypertension?
    a. Sedatives and reserpine
    b. Thiazide diuretics and reserpine
    c. Sedatives and thiazide diuretics
    d. Guanethidine and ganglionic blocking agents
  95. Which of the following beta-adrenergic receptor blocking agents is thought to be cardioselective?
    a. Nadolol
    b. Timolol
    c. Metoprolol
    d. Propranolol
  96. Antiarrhythmic drugs, such as quinidine, suppress certain cardiac arrhythmias by
    d. Increasing the refractory period of cardiac muscle
  97. Most drugs useful in the treatment of cardiac arrhythmias act primarily by
    e. Increasing the refractory period of cardiac muscle
  98. The most important pharmacologic action of drugs that suppress cardiac arrhythmias is
    a. Blockade of the vagus nerve
    b. Stimulation of cardiac ATP-ase activity
    c. Blockade of the Beta-adrenergic receptor
    d. Stimulation of the beta-adrenergic receptor
    e. Increased refractory period of cardiac muscle
  99. Lidocaine produces its antiarrhythmic effects by
    • b. Decreasing cardiac excitability
    • (b) arrhythmias are defined as any abnormality of the normal
    • sinus rhythm of the heart due to disease or injury induced damage to the impulse conducting systems.
    • They also result from the development of ectopic pacemakers or abnormal pacemaker rhythms.
    • Drugs such as lidocaine are used to normalize these rhythms. Lidocaine, a local anesthetic, depresses cardiac excitability, answer (b). The refractory period
    • of cardiac muscle is increased, thus slowing the heart down.
    • All of the other alternatives given would exacerbate the arrhythmia.
  100. When digitalis is used in atrial fibrillation, the therapeutic objective is to
    • c. Decrease the rate of A-V conduction
    • (c)
  101. Nitroglycerin dilates the coronary arteries in angina pectoris by
    Direct action on smooth muscle in the vessel walls
  102. Propranolol is of value in treating angina pectoris because it
    • Prevents chronotropic responses to endogenous epinephrine emotions and exercise
    • (e)
  103. 22. Which of the following is NOT characteristic of the thiazide diuretics?
    a. Increase renal excretion of sodium and chloride
    b. Increase renal excretion of potassium
    c. Increase the toxicity of digitalis
    d. Exacerbate existing diabetes
    e. Cause hypokalemia
    f. Cause hypoglycemia
    • (f) first off, how can you have an option (f)?!
    • (a) is how diuretics lower BP,
    • (b) is why they can cause hypokalemia, which is conveniently option (e), and hypokalemia can potentiate digitalis
    • induced arrythmias option(c).
    • They apparently can also cause hyperglycemia, which would relate to option (d).
  104. The most useful diuretic drugs act by
    a. Increasing the glomerular filtration rate
    b. Decreasing the renal reabsorption of sodium
    c. Decreasing the renal excretion of chloride
    d. Increasing the renal reabsorption of potassium
    e. Increasing the secretion of antidiuretic hormone
    • (b) people with high BP are always told to reduce salt intake, since high sodium levels cause fluid retention which can
    • increase BP, so ipso facto, reducing renal reabsorption of sodium makes BP go down