Non-Beta Lactam Antibiotics Flashcards Preview

Ther 201 LE 3 > Non-Beta Lactam Antibiotics > Flashcards

Flashcards in Non-Beta Lactam Antibiotics Deck (34):
1

Antifolate drugs MOA

inhibits folic acid (THF acid synthesis)

2

Cortimoxazole = _ + _

Sulfonamides
Trimethoprim

3

sulfonamides MOA

inhibits pteridine synthetase (since it is structurally similar to PABA) (PABA + PS)

4

trimethoprim MOA

inhibits DHF reductase (DHF -> THF)

5

Cortimoxazole indications

typhoid fever (1st line)
Pneumocystis jirovecii pneumonia
toxoplasmosis
nocardiosis

6

PK notes Cortimoxazole

wide distribution - crosses PLACENTA

7

Drugs which inhibit protein synthesis via 30S ribosome

Aminoglycosides
Tetracyclines

8

Drugs which inhibit protein synthesis via 50S ribosome

Macrolides
Chloramphenicol
Clindamycin

9

Aminoglycoside MOA (3)

1) inhibits initiation complex formation
2) misread RNA -> wrong protein
3) breaks up polysomes

10

clinical use of Aminoglycosides ALONE

UTI
//
combine with beta-lactam for other

11

adverse effects of Aminoglycoside

ototoxicity (irrev)
nephrotoxicity and neuro block (rev)
allergic rxn

12

given to reverse neuromuscular blockade due to Aminoglycoside

Ca gluconaate, Neostigmine

13

Tetracycline MOA

binds to 30S, blocks tRNA binding to Acceptor site on the mRNA ribosome complex - no peptide elongation

14

bacterial resistance mechanisms against tetracycline

1) impaired influx or impaired efflux by active transport protein pump Tet(AE) - G-
2) protects ribosome by producing proteins which interfere with tetracycline binding Tet(M) - G+

15

How are tetracyclines classified? What are the classifications

By half-life
1) Short-acting (6-8h)
2) Intermediate-Acting (12h)
3) Long-acting (16-18h)

16

Short-acting tetracycline drugs

Chlortetracycline
Oxytetracycline

17

Intermediate-acting tetracycline drugs

Democlocycline
Methacycline

18

Long-acting tetracycline drugs

Doxycycline
Minocycline
Tigecycline

19

Longest acting tetracycline and half-life

Tigecycline, 36 hours

20

Difference of route of excretion of long acting tetracyclines

Long-acting by biliary excretion unlike others which are renal

21

Tetracycline clinical use

Chlamydia
Mycoplasma pneumonia
cholera (short term ok for <8yo)
leptospirosis

22

tetracycline contraindicated for

pregnant & <8yo

23

Aminoglycoside and TEtracycline difference in chemical properties

A - not acid stable, irreversibly binds
T - acid stable, reversible

24

Macrolides MOA

inhibit translocation of tRNA from A to P site

25

Macrolides examples

Erythromycins
Clarithomycin
Azithromycin
Roxithromycin

26

Macrolides Pharmacokinetics

wide distribution but poor CSF penetration

27

Drug interaction with Macrolides

(1)They decrease CYP1A2 and CYP3A3/4 levels -> elevated effects of other drugs
(2) +Terfenadine or Astemizole -> cardiac arrhythmias

28

advantages of newer macrolides

less GI side effects

29

macrolide indications

atypical pneumonia
whooping cough (Borderella pertussis)
Gastroeneteritis
Diphtheria
Penicillin Hypersensitivity alternative drug

30

chloramphenicol MOA

binds to 50S ribosomal subunit and inhibits transpeptidation (blocks P-A transfer)

31

chloramphenicol chemistry

oral - palmitate
IV - succinate

palmitate inactive must be hydrolyzed in s.i. pure chloramphenicol does not dissolve in water

32

T/F Oral route is preferred than IV route for chloramphenicol

T
succinate is an inactive produg, must be hydrolysed first but process is incomplete losing 30%

33

Chloramphenicol indications

reserved for serious infections
H. influ - meningitis
1st line for typhoid feer
brain abscess

34

Adverse effects of Chloramphenicol

Idiosyncratic aplastic anemia
Gray Baby syndrome
Optic Neuritis