Antibacterials/antibiotics

Question 1

Beta-lactams

MOA

Answer 1

Disrupt bacterial cell wall or membrane

Question 2

Penicillins

Answer 2

-PO absorbtion affected by acid/food
-renal tubular secretion for elimination- sensitive to renal fxn
AE: mostly due to hypersensitivity rxn: rash/allergy

Question 3

Natural: penicillin
Extended spectrum: ampicillin, amoxicillin
Anti-staph: methicillin, natacillin, oxacillin, dicloxacillin
Anti pseudomonal: pipericillin, ticaricillin*

Answer 3

“Classes” of penicillins

Question 4

Cephalosporins

Answer 4

Organized in generations due to years and spectrum
AE: allergy (cross rxn with PCN)
CNS ( fever, seizure), hemolytic anemia, bone marrow suppression
Possible disulfiram rxn with cefotelon
Diarrhea, C.diff, interstitial nephritis

Question 5

Carbapenems

Answer 5

-IV
Severe infections
Cross rxn with PCN and cephalosporins
* seizure risk

Question 6

Impenem, meropenem, ertapenem, doripenem

Answer 6

Carbapenems

Question 7

Monobactams

-Aztreonam

Answer 7

-IV
Limited to G- rods
No cross rxn with PCN

Question 8

Tetracyclines

Answer 8

MOA: interfere with bacterial protien/DNA/RNA synthesis via ribosomes (inhibit protien synthesis)
-bacteriostatic
Broad spectrum
AE: tooth discolor, bone problems, avoid in pregnancy, photosensitivity, hepatotoxicty, Caution with expired meds

Question 9

Macrolides

Answer 9

MOA: interfere protein synthesis via ribosomes
-bacteriostatic
AE: abdominal pain, N/V/D, QTc prolongation, may increase GI motility- erythromycin, azythromicin

Question 10

Erythromycin
Azythromicin (Zithromax)
Clorithromycin

Answer 10

Macrolides

Question 11

Fluoroquinolones

Answer 11

MOA: disrupt DNA transcription/ translation
-bacteriocidal
-resistance is concern
-active against anaerobes
-renal elim
Toxicities: CNS stimulation, tendon rupture, QT prolongation, hyper/hypoglycemia

Question 12

Sulfonamides

Answer 12

MOA: interfere with protein/DNA/rna synthesis by blocking folic acid 
-broad spectrum (mersa) 
-hepatic met-renal elim 
AE: allergy( cross rxn to other sulfa-sulfonylureas) 
Hemolytic anemia 
Photosensitivity 
Skin rxn 
Megoblastic anemia 
INX: warfarin, sulfonylureas

Question 13

Sulfamethoxazole, sulfisoxazole, sulfadiazine, sulfaacetamide

Answer 13

Sulfonamides

Question 14

Amino glycosides

Answer 14

MOA: inhibit protien synthesis via ribosomes 
-bacterialcidal 
*used in highly severe G- infections 
-renal elim 
AE: *nephrotoxicity 
*ototoxicity
Neuromuscular blockade

Question 15

Gentamicin, tobramicin, amikacin

Answer 15

Amino glycosides

Question 16

Penicillins
Cephalosporins
Carbapenems
Monobactams

Answer 16

Beta lactam type antibiotics

Question 17

Vancomycin

Answer 17

MOA: disrupts bacterial wall or membrane
-G+ only
* use is restricted to treat G+ infections, last resort med
*no oral absorbtion,90% renal elim
-PO, IV
IV doesn’t pass thru gut-won’t treat Cdiff
*oral only for Cdiff
Can drink IV
AE: phlebitis, red man syndrome (allergic rxn), *nephrotoxicity, *ototoxicity

Question 18

Clindamycin (cleocin)

Answer 18

MOA: inhibits bacterial protien synthesis via ribosomes
-will not treat Cdiff( promotes it)
AE: diarrhea, hepatotoxicty, rashes, blood dyscasias

Question 19

Metronidazole (Flagyl)

*Cdiff

Answer 19

MOA: disrupts DNA transcription/translation

• anti protazoal
• spectrum: anaerobes
• IV & PO will treat Cdiff
• gut and abcesses

AE: disulfiram rxn

Question 20

Rifaximin (xifaxin): inhibits RNA synthesis, limited to systemic absorption

Fidaxomicin (dificid): only for Cdiff

Answer 20

Anti Cdiff drugs 
Including metronidazole (Flagyl)

Question 21

Telethomycin (ketek): liver toxic, drug inx
Linezolid (zylox), tedizolid (sivextro): VRE, MRSA
Quinipristin/dalfopristin (synercid)
Daptomycin (cubicin)
Telovancin (vibativ): caution with renal dysfunction

Answer 21

Unique antibacterials

• use is limited/restricted for use only with highly resistant organisms
• restricted to limit resistance

Question 22

Tuberculosis: mycobacterium (lipid and mycolic acid in cell wall)

• slowly growing
• able to become resistant very fast due to mutation

Answer 22

Isoniazid (INH)

Rifampin (rifamycin antibiotic)

Question 23

Isoniazid (INH)

Anti TB

Answer 23

MOA: inhibits synthesis of mycolic acid
*1st choice to treat TB
AE: neuropathy, hepatotoxicty, lupus like syndrome
*peripheral neuropathy
* hepatotoxicty (anorexia, nausea, jaundice)

Question 24

Rifampin (rifamycin type antibacterial)

Anti TB

Answer 24

MOA: inhibits RNA polymerase
* strongest enzyme inducer ever (increase metabolism of all drugs)
AE: hepatotoxicty ( increase LFTs), discoloration of body fluids (orange) will stain contacts, N/V, anorexia, flushing, inching,,flu like symptoms