antibiotics for osteomyelitis and skin infections med chem

Question 1

tetracycline drugs

Answer 1

tetracycline
monocycline
doxycycline
tigecycline

Question 2

tetracycline MoA

Answer 2

interacts with 30S subunit of ribosome and sits in A site to prevent elongation (bacteriostatic)

Question 3

tetracycline general pharmacophore

Answer 3

4 rings and dimethylamine pointing into the board

Question 4

ways to inactivate tetracyclines

Answer 4

• make dimethylamine come out of the board
• dehydration of OH on north side
• breaking C ring through intramolecular reaction

Question 5

avoid taking tetracyclines with what

Answer 5

multivitamins and milk because of chelation with ions

Question 6

tetracyclines clinical use

Answer 6

• Gm+
• MRSA
• limited Gm-

Question 7

tetracycline resistance

Answer 7

widespread in forms of

• efflux
• mutations in ribosome
• cell wall variation

Question 8

side effects of tetracyclines

Answer 8

• light sensitivity
• severe kidney damage
• incorporation into bones and teeth

Question 9

tigecycline unique structure feature

Answer 9

the claw on the tetracycline ring that prevents efflux based resistance

Question 10

tigecycline clinical use

Answer 10

broad spectrum, typically saved for instances of resistance

hits basically everything but pseudomonas

Question 11

clindamycin MoA

Answer 11

sits in 50S peptidyltransferase to inhibit the enzyme

Question 12

clindamycin clinical use

Answer 12

• Gm+ (staph, strep)
• used w/ aminoglycosides for Gm-
• some anaerobes
• used if PCN allergy
• PO/IV

Question 13

clindamycin side effects

Answer 13

• GI

- pseudomembranous colitis caused by C.difficile

Question 14

linezolid MoA

Answer 14

prevents formation of 70S subunit complex by binding w/ 50S subunit

Question 15

linezolid clinical use

Answer 15

• Gm+
• MRSA
• VRE
• IV/PO

Question 16

linezolid resistance

Answer 16

still rare but can be seen as:

• point mutation of ribosome
• efflux pump in Gm-

Question 17

linezolid side effects

Answer 17

• monoamine oxidase inhibitor, so avoid w/ tyramine foods and serotonergic drugs
• bone marrow suppression

Question 18

linezolid monitoring

Answer 18

weekly blood counts

Question 19

synercid

Answer 19

• IV only
• combo of dalfopristin and quinupristin
• 30:70 ratio quinupristin:dalfopristin because dalfo binding first increases affinity for quinupristin

Question 20

synercid MoA

Answer 20

binds to A and P sites to interfere with tRNA binding and misalignment of P site

Question 21

mupirocin MoA

Answer 21

binds to Ile-tRNA synthetase to prevent incorporation of Ile into proteins

Question 22

mupirocin clinical use

Answer 22

• used topically or nasally because it is hydrolyzed in vivo

- broad spectrum activity, good against staph and strep

Question 23

mupirocin resistance

Answer 23

mutations in synthetase enzyme prevents binding

Question 24

vancomycin MoA

Answer 24

“hugs” cross link area of peptidoglycan to prevent transpeptidase cross link AND prevents sugars from cross linking

Question 25

vancomycin clinical use

Answer 25

- narrow spectrum Gm+ - used for C.diff and enterococci - last resort for MRSA - PO/IV

Question 26

vancomycin resistance

Answer 26

D-Ala D-Ala becomes D-Ala D-Lactate to reduce hydrogen bonding

Question 27

vancomycin resistant enterococci background

Answer 27

- 2nd most common Gm+ in hospitals | - high moretality

Question 28

treatments for VRE

Answer 28

synercid linezolid cubicin (daptomycin)

Question 29

linezolid route

Answer 29

oral and IV

Question 30

clindamycin route

Answer 30

oral

Question 31

tigecycline route

Answer 31

IV

Question 32

telavancin and dalbavancin MoA

Answer 32

- disrupts peptidoglycan cross linking | - long FA chain anchors it in membrane helping with affinity

Question 33

telavancin route

Answer 33

IV

Question 34

dalbavancin route

Answer 34

IV

Question 35

telavancin and dalbavancin clinical use

Answer 35

- MRSA | - some vancomycin resistant strains

Question 36

difference between telavancin and dalbavancin

Answer 36

half life | dalbavancin has once weekly dosing

Question 37

daptomycin MoA

Answer 37

creates a potassium ion channel leading to membrane depolarization

Question 38

daptomycin clinical use

Answer 38

``` Gm+ -resistant strep -resistant staph -resistant entero MRSA VRE -IV ```

Question 39

daptomycin side effects

Answer 39

- elevated serum creatinine phosphkinase | - rhabdomyolysis

Question 40

daptomycin monitoring

Answer 40

signs of muscle pain or weakness

Question 41

tetracyclines contraindications

Answer 41

- pregnant females | - children under 8

Question 42

vancomycin IV side effects

Answer 42

- GI | - red man syndrome