Unit 1 Antibiotics part 2

Question 1

Clindamycin

Answer 1

Gram + infections and anaerobes, no G-
Aspiration pneumonia, Cellulitis
Pre-op anti-biotic
“D” test to cover MRSA

ADR/BOX: C DIff and AAD

Question 2

Linezolid Uses

Answer 2

Gram + ONLY
MRSA infections, Pneumonia (VRE-)
Restricted
CONTRA: concurrent or recent use of MAOIs

Question 3

Aminoglycosides

Answer 3

Gentamicin and Tobramycin
Gram - including CRE, severe gram - infections, multi-drug resistant organisms, pre-op antibiotic
Require a certain concentration to be reached for a full effect (Conc. dependent)
Peaks and troughs. Weight based and utilized to minimize toxicity while killing bacteria

Question 4

Aminoglycosides Uses

Answer 4

Gram - including CRE, multi-drug resistant organisms, pre-op antibiotics

Question 5

Safety of Aminoglycosides

Answer 5

Ototoxicity: tinnitus, irreversible, STOP treating with it

Neuromuscular Blockade: Paralysis of patient

Question 6

Extended Interval vs Traditional Dosing

Answer 6

E: low peak high freq

T Very high peak, gradual decline

Question 7

Sulfonamides

Answer 7

Anti metabolites
Cellulitis, UTI, G+, MRSA
ADR: hyperkalemia and hypersensitivity

Question 8

Sulfonamides ADRs

Answer 8

Hyperkalemia: block Na channels in nephrons
Hypersensitivity: Delayed (SJS and TEN) or immediate (typical rash, anaphylaxis)

Question 9

Silvadene, Sulfadiazine, Sulfacetamide

Answer 9

Acne topical sulfacetamide
Burn topical silvadene
Toxoplasmosis treatment sulfadiazine

Question 10

Fluoroquinolones

Answer 10

Broad spectrum. G+/-, Pseudomonas, atypical organisms.
Moxifloxacin only: Anaerobes
Levofoxacin: Levaquin: respiratory
Ciprofloxacin: Cipro: non-respiratory, feces
ADR: tendinitis and tendon rupture, peripheral neuropathy, CNS effects
Requires renal adjustment
Absorption decreased by cations

Question 11

Metronidazole

Answer 11

Flagyl
Anaerobic infections (vaginosis), surgical prophlyaxis.
BEST anaerobic bacterial agent
Contra: 1st trimester pregnancy, alcohol: Disulfiram rxn = vomiting
ADRs: nausea, headache, metallic taste (old penny)
BOX: carcinogenic in rats
50% dose in severe liver impairment

Question 12

Rifampin

Answer 12

Tb
Never used ALONE
Contra: A lot. CYP 3A4 and other CYPs. Big inducer. Causes drug interactions (HIV and Hep C drugs)
ADR: bright body fluids

Question 13

Nitrofuantoin

Answer 13

Macrobid(2/day) and Macrodantin (4/day)
UTI prophylactic and regular
only work in urine
Contra: Renal impairment, jaundice, or hepatic dysfunction from prior use
Avoid use in CrCl

Question 14

Tetracyclines

Answer 14

G+, G-, and atypicals, anthrax, malaria, syphilis, cholera, lyme disease
Doxycycline (most used): pneumonia, cellulitis, COVERS MRSA
Tetracycline, minocycline: acne

ADR: tooth mottling, GI irritation, photosensitivity

Question 15

Macrolides

Answer 15

Cover G+, G-, atypicals
Azithromycin: Upper respiratory infections
Erythromycin: Acne and GI motility issues
ADR: Azithromycin has QT prolongation = increased risk of fatal heart rhythms