Antibiotics

Question 1

Bacitracin

Answer 1

Cell Wall Inhibitor (PDG)

gram + only; ung only

Polysporin and Neosporin (soln and ung)
- in soln, replaced with gramcidin

Question 2

Vancomycin

Answer 2

Cell Wall Inhibitor (PDG)

gram + and MRSA; IV and intravitreal only

AE: nephrotoxicity, hepatotoxicity, red man syndrome

Fortified Abx for severe bacterial infections

Question 3

PCN

Answer 3

Cell Wall Inhibitor (Transpeptidase)

oral/injectables only

Augmentin (amoxicillin and Clavulanic Acid)

• Dose: 500 or 875mg / 125mg tablet; 1 tablet PO bid x 5-14 days
• take with food

AE: allergy, diarrhea

Contraindicated in GI or liver/renal impairment

Question 4

Cephalosporins

Answer 4

Cell Wall Inhibitor (Transpeptidase)

orals and injectables
if PCN allergy (need 3rd gen or higher)

Question 5

Cefazolin

Answer 5

1st gen: gram + and some -

IV and fortified for corneal ulcers

Question 6

Cephalexin

Answer 6

1st gen

500mg bid x 5-14 days

Question 7

Cefaclor

Answer 7

2nd gen: gram - and some +

oral capsule good for children

Question 8

Cefdinir

Answer 8

3rd gen: better - and some +

oral

Question 9

Ceftriaxone

Answer 9

oral, IM (gon), IV (orbital cellulitis)

Question 10

Ceftazidime

Answer 10

intravitreal injection

Question 11

Protein Synthesis Inhibitors

Answer 11

30s: Aminoglycosides and Tetracyclines
50s: macrolides, clindamycin, linezolid

Question 12

Aminoglycosides

Answer 12

gram - coverage and available in soln/ung except Amikacin (intravitreal)

oral: ototoxicity, paralysis, and nephrotoxicity

topical: allergic contact dermatitis, SPK
- has some + coverage

Pseudomonas (T > G >N)

Question 13

Tobramycin

Answer 13

covers MRSA

can be fortified for corneal ulcer

Tobradex or Zylet

Question 14

Gentamicin

Answer 14

can be fortified for corneal ulcer

Question 15

Neomycin

Answer 15

broad spectrum except not pseudomonas or strep

Neosporin: neo and poly and bacitracin

Maxitrol: neo and poly and dexamethasone

Question 16

Tetracyclines

Answer 16

30s Protein Inhibitor
oral and injectables with gram -/+ and MRSA and chlamydia

AE: gastric discomfort, phototoxicity, not for pregnant or kids, hemolytic anemia, benign intracranial HTN

Question 17

Doxycycline

Answer 17

DOC for chlamydia
- 100mg PO bid x 1 week

used to treat rosacea, pterygium, RCE

Question 18

Macrolides

Answer 18

50s protein inhibitor

orals and injectables
- orals prolong QT prolongation, hepatic issues, gastric discomfort

E and A have ophthalmic preparations

Question 19

Erythromycin (macrolide)

Answer 19

narrow spectrum

ung: ocular surface infection and prophylaxis of ophthalmic neonatorum
oral: used as chlamydia (NOT DOC)

Question 20

Azithromycin (macrolide)

Answer 20

oral, IV and ophthalmic

DOC for Chlamydia
- 1000mg one time
Azasite: soln for bacterial conjunctivitis

Question 21

Clindamycin

Answer 21

serious infections with PCN allergy

Question 22

Linezolid

Answer 22

oral and injectable but MANY AE and narrow spectrum so rarely used

QT prolongation

Question 23

DNA Synthesis Inhibitors

Answer 23

DNA gyrase and Topo IV: FLQ

Folic Acid: Trimethoprim and Sulfonamides