Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pulmonology > TB Drugs - Pharm > Flashcards

TB Drugs - Pharm Flashcards

1
Q

“Cidal” antibiotics require the organism to do what?

A

Organism must be growing in order to have an effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Significant therapy type and duration for treating TB?

A

Combination therapy for a prolonged course of therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why must combination therapy be used?

A

Myobacterium will become resistant to single agent therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

List 3 rafamycins?

A

Rifampin, Rifabutin, rifapentine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Compare CYP induction b/t and rifampin, rifabutin, & rifapentine

A

Induction potency: Rifampin > Rifapentine > Rifabutin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Compare 1/2 life b/t rifampin, rifabutin, & rifapentine

A

1/2 life: Rifapentine > rifampin or rifabutin

can be given 1x a week.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

1st line therapy for M. tuberculosis?

A

Isoniazid + rifampin + pyrazinamide + ethambutol/streptomycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

1st line therapy for M. avium complex?

A

Clarithromycin + ethambutol/clofazimine/ciprofloxacin/amikacin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

In HIV patients, rifabutin can decrease drug interactions b/t?

A

decrease drug interaction with PIs (protease inhibitors) and NNRTIs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

List the possible treatment methods for latent TB infection. Which has been proven to be most effective? Why?

A
  • Isoniazid 9 months
  • isoniazid 6 months
  • Isoniazid & Rifapentine 3 months (best option, increased likelihood of compliance/shortest duration of treatment but with Directly Observed Therapy (DOT))
  • Rifampin 4 months
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which 2 drugs should not be combined for treatment of latent TB? Why?

A

Rifampin and pyrazinamide, due to reports of severe liver injury and deaths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Isoniazid & Rifapentine not recommended for what subset of patients (4) ?

A
  • Children less than 2 y/o
  • HIV-infected pts receiving antiretroviral treatment - druginteractions
  • pregnant women or women expecting to become pregnant
  • pts who have LTBI w/ presumed INH or RIF resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

2 phases of ACTIVE TB treatment. Duration of each phase?

A

Initial (8 weeks) and continuation phase (18 weeks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Preferred treatment regimen of ACTIVE TB (initial and continuation phase)

A 
Initial phase (8 weeks w/ 56 doses) - Daily Isoniazid, Rifampin, pyrazinamide, & Ethambutol
Continuation phase (18 weeks) - Daily isoniazid and rifampin for 126 doses or twice weekly Isoniazid & rifampin for 36 doses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

MOA of isoniazid in mycobacterial cells?

A

Interferes with mycolic acid synthesis, disrupting the bacterial cell wall synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Isoniazid is bactericidal against what?

A

Bactericidal against rapidly dividing bacilli, such as those found in extracellular cavitary lesions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Isoniazid is bacteriostatic against what?

A

Bacteriostatic against:

  • organisms found within closed caseous lesions
  • macrophages that divide slowly and intermittently
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Isoniazid alone and active TB? Good, bad, ugly? why?

A

Isoniazid not used alone against active TB, bc resistant organisms rapidly emerge. Similar resistance can be seen with pyrazinamide, ethambutol and rifampin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe route of administration of isoniazid

A

Rapidly absorbed from GI tract with oral dose, can be given IM too

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe distribution of isoniazid. Where specifically can it distribute to (2 locations)?

A
  • Distributed throughout all tissue and fluids.
  • Penetrates inflamed meninges and achieves therapeutic levels in CSF
  • Crosses placenta and can get into breast milk
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where is isoniazid metabolized? How? Key feature of metabolization? 1/2 life features?

A
  • Metabolized in liver via acetylation (primarily)
  • polymorphisms in acetylation capacity (“fast” vs “slow”) cause considerable interpatient variability in plasma concentration.
  • 1/2 life can vary 1 - 4 hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Isoniazid and CYPs, what about them?

A

Isoniazid induces CYPs; this can impact concurrent CYP substrate therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Route of elimination of isoniazid?

A

75% of drug and inactive metabolites excreted in urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Adverse effects of isoniazid?

A

Peripheral neuropathy, hepatotoxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

“stocking glove” associated with adverse effects of which drug? As a result of competition with what other drug?

A

Isoniazid. competition with pyridoxal phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How to you correct “stocking glove” symptoms seen with isoniazid?

A

Vitamin B6 supplementation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Hepatitis occurs in what % of patients receiving isoniazid?

A

2%

28
Q

Caution should be administered if going isoniazid with what other types of drugs?

A

Other drugs that are also hepatotoxic, like rifampin

29
Q

What decreases drug absorption of isoniazid?

A

Antacids (especially aluminum salts)

30
Q

What drug can worsen parkinson’s? MOA?

A

Isoniazid, inhibits dopadecarboxylase, reducing effectiveness of LEVODOPA therapy and worsening parkinsons

31
Q

Isoniazid specifically induces which CYP? Which drug can this affect?

A

Induces CYP2E1, can increase acetaminophen toxicity

32
Q

MOA of Rafamycins?

A

Inhibits RNA synthesis (binds Beta subunit of the Mb RNA polymerase)

33
Q

Describe resistance mechanism seen with rafamycins

A

alteration in Beta subunit of the RNA polymerase prevents drug from binding to it.

34
Q

Are rafamycins bactericidal or bacteriostatic?

A

Bactericidal

35
Q

Giving a rafamycin alone increases what?

A

resistance to drug

36
Q

Rifampin absorption impaired by what?

A

food or para-aminosalicylic acid

37
Q

Distribution of rifampin?

A

penetrates all tissues well, including CSF. 75-85% is protein bound

38
Q

Method of metabolism of rifampin? Key feature of this type of metabolism

A

Deacetylated in liver. Deacetylated rifampin still retains full antibacterial activity; however, it is not reabsorbed following elimination into the GI tract

39
Q

Route of excretion of rifampin? Important point regarding route of excretion?

A

Primarily in bile. 30% unchanged, which will be reabsorbed via enteroehaptic circulation.

40
Q

Which drug has a shortened 1/2 life in the 1st two weeks of treatment? Mechanism behind this

A

Rifampin. Hepatic microsomal enzymes are auto induced, leading to increased deacetylation, shortening the 1/2 life

41
Q

Patient has orange-red tears, urine, and/or saliva? What drug causes this

A

Rifampin. will discolor body fluids orange-red

42
Q

Hepatotoxicity seen in what drugs?

A
  • Isoniazid (in addition to peripheral neuropathy)
  • rifampin
  • pyrazinamide (at larger doses)
  • ethionamide
43
Q

Rifampin induces what enzyme?

A

cytochrome p450

44
Q

Which drug is only effective against actively dividing bacilli?

A

ethambutol

45
Q

Is ethambutol bactericidal or bacteriostatic?

A

low doses - bacteriostatic

higher doses - bactericidal

46
Q

MOA of ethambutol?

A

inhibits arabinosyl transferase preventing synthesis of peptidoglycan cell wall, causing increased cell permeability

47
Q

Where in body does ethambutol distribute to?

A

concentrates in kidneys, lungs, saliva. Also in CSF with inflamed meninges and cross placenta(like isoniazid)

48
Q

Route of elimination of ethambutol? Consequence of this?

A

Excreted in urine (50% of dose unchanged) - can cause renal dysfunction

49
Q

Optic neuritis is an adverse reaction of what drug?

A

Ethambutol

50
Q

Optic neuritis as a result of ethambutol causes what to occur in patients? Reversibility?

A

decreased visual acuity, loss of color discrimination. Reversible. Must prevent by giving monthly visual exams during therapy

51
Q

Patient begins experiencing gout symptoms. Which drug (s) are you thinking might have caused this?

A

Ethambutol or pyrazinamide can cause hyperuricemia, leading to gout

52
Q

Best environment for pyrazinamide to work in?

A

Most effective at intracellular sites where M. tuberculosis replicates slowly, such as within macrophages

53
Q

Which drug (s) can be given IM?

A

Capremycin and Isoniazid (more likely given orally)

54
Q

Pyrazinamide route of elimination?

A

metabolized in liver and excreted in the urine (70%); therefore dose adjustment should be considered in severe renal dysfunction

55
Q

Arthralgia’s reported in 40% of patients taking what medication?

A

Pyrazinamide

56
Q

Which drug (s) are used in multi drug resistant therapy?

A

cycloserine, & Ethionamide,

57
Q

MOA of cycloserine

A

Blocks cell wall synthesis

58
Q

Route of excretion of cycloserine

A

excreted unchanged by renal mechanism

59
Q

Adverse effects of cycloserine?

A

Involve CNS - headaches, tremors, vertigo, confusion

60
Q

Patient has epilepsy, which drug do you not give?

A

Cycloserine

61
Q

MOA of ethionamide?

A

inhibits peptide synthesis

62
Q

Which drug is reserved as a last line agent due to its toxicity? What type of toxicities?

A

Ethionamide. cause GI, neurologic and hepatotoxicity

63
Q

Which drug(s) are reserved for Extensively drug resistant TB

A

Any fluoroquinolone and at least 1 of 3 other injectable drugs (amikacin, kanamycin, or capremycin)

64
Q

Nephrotoxicity and ototoxic, which drug?

A

Capreomycin

65
Q

Patient may develop eosinophilia after taking this drug

A

Capreomycin

66
Q

Testing for visual disturbances prior to and during therapy are recommended for which drug?

A

Ethambutol, due to potential of developing optic neuritis

Pulmonology (31 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions