antimycobacterials Flashcards Preview

Pharm main > antimycobacterials > Flashcards

Flashcards in antimycobacterials Deck (49)
1

First Line antimycobaterials

Isoniazid, Rifampacin, Pyrinizinamide, Ethambutol

2

INH- MOA

Inhibits mycolic acid synthesis

3

INH activation

KatG- only in Mb

4

INH & liver enzymes

p450 inhibitor, metabolized in liver, various rates of acetylation

5

INH MOR

katG mutation

6

INH- AE

Hepatitis, B6 deficiency- peripheral neuropathy, give pyridoxine, Inhibition of Phenytoin metabolism- ataxia

7

Rifampin- MOA

binds to beta subunit of Mb RNA pol --> inhibits transcription

8

RIF & liver enzymes

CYP450 inducer

9

RIF excretion

mostly feces, some urine

10


RIF AE



Reddish/ brown Urine, skin eruptions


11

RIF drug interactions

inc elimination of other drugs esp Birth control and HIV proteases- monitor the level

12

RIfabutin

doesn't affect CYP450 so use in AIDs patients so don't inc elimination of PI

13

Rifampimicin

Used for leprosy

14

Pyrizinamide (PZA)- MOA

Pyrizinamidase converts it to pyrizinmatoic acid --> unknown MOA

15

PZA 1/2 life

9 hr

16

PZA- distribution

well distributed in tissues but concentrates in cells

17

PZA activity

active in acidic environments ie lysozomes inside of macropahges

18

PZA AE

Hyperuricemia- Pyrazinoic acid inhibits renal secretion of Uric acid --> Gout monitor SGOT (liver enzyme) and uric acid, Heptatitis, Arthralgia, fever, skin rashes

19

Ethambutol MOA

inhibits arabinosyl tranferase --> inhibits bac wall synthesis. Bacerial static

20

Ethambutol distribution

most tissues, including CNS --> used for TB meningitis

21

Ethambutol AE

Retrobulbar neuritis- Optic neuritis w/o swelling of optic disc. R/G color blindness- Monthly tests for visual acuity. Peripheral neuritis, HA, Rash

22

Streptomycin (SM)- use

occasionally used in conjunction with first line tax

23

SM- admin

IV/ IM

24

SM- AE

Ototoxicity- vistibular and auditory, renal injury, hypersensitivity

25

SM- MOA

binds 30s subunit of bac ribosome- prevents initiation complex formation. Inhibits translation

26

Paraminosalicylic Acid- PSA- MOA

competes with PABA for Mb dihyropterase synthase, interferes with folic acid and thus DNA synthesis. bacteriastatic

27

PSA- admin

oral, well absorbed, always with food

28

PSA toxicity

GI- nausea, abdominal pain, diarrhea, nausea if not given w/ food. Goiter, hypothyroidism. Anemia

29

Ethionamide- MOA

Inhibits mycolic acid synthesis

30

Ethionamide excretion

ethionamide sulphoxide- kidney excretion

31

Ethionamide - AE

pyridoxine deficiency , GI- N/D/ pain, hepatotoxicity, allergic reactions

32

Clofazamine- uses

Leprosy and Tb

33

Clofazoamine- MOA

inhibits DNA synthesis

34

Clofazamine T1/2

10 days

35

Clofazamine distribution

widely. Concentrates in reticuloendothelil system and is slowly let out, partially accounts for long half life

36

Clofazamine - AE

Drug accumulation in tissues turns- skin, urine, and feces a red brown color, so people with leprosy don't like it b/c it marks them. GI disturbances

37

Cycloserine/ kanamycin- MOA

inhibits cell wall synthesis

38

Cycloserine/ Kanmycin- use

rarely used due to poor efficacy and adverse eventes

39

Fluroquinolones-

Ciprofloxacin, Moxifloxacin, Levofloxacin

40

Fluroquinolones- MOA

inhibit topoisomerase II

41

Dapsone- use

Tx leprosy

42

Dapsone- MOA

inhibits folate synthesis

43

Dapsone- excretion

excreted into bile, reabsorbed, excreted in urine

44

Dapsone- AE

well tolerated. Fever, GI, rash, exoliative dermatitis

45

Dapsone Contratindications

Don't give to someone with sulfa drug allergies

46

Second line Tb tx

Streptomyocin, Paramino Salacylic Acid, Ethionamide, Clofazamine, Cyloserine/ Kanomycin, Fluroquinolones, capreomycin

47

Paucibacillary Tb- Tx

Rifampin& Dapsone for 6 months. Single lesion- Rifampin, ofloxacin, Minocycline

48

Lepromatous MB- Tx

Rifampin, Dapsone, Clofazamine- 12 mos

49

M. avium Tx

Azithromycin, Ethambutol, Rifabutin, Fluroquinolones