Aminoglycosides, Sulfonamides, Fluoroquiolones

Question 1

What is the prototype for aminoglycosides?

Answer 1

Gentamicin

Question 2

Therapeutic use for Gentamicin?

Answer 2

serious aerobic gram negative infections (E coli, Klebsiella pneumoniae, proteus mirabilis, and pseudomonas aeruginosa).

Question 3

MOA of Gentamicin?

Answer 3

Bactericidal: inhibits protein synthesis in bacteria at level 30S ribosome

Question 4

Adverse effects of Gentamicin?

Answer 4

ataxia, vertigo, ototoxicity, nephrotoxicity, and inhibition of neuromuscular transmission (weakness or worsen myasthenia gravis)

Question 5

Contraindications for Gentamicin?

Answer 5

hypersensitivity to gentamicin or other aminoglycosides

Question 6

Gentamicin precautions?

Answer 6

renal impairment, hearing impairment, myasthenia gravis

Question 7

Gentamicin interactions?

Answer 7

PCN: ↓ effects

Loop diuretics: ↑ risk for nephrotoxicity and ototoxicity

Question 8

Route, metabolism, and excretion of Gentamicin?

Answer 8

Route: IM and IV; rapid onset
Metabolism: NOT by liver
Excretion: > 90% kidneys

Question 9

Gentamicin should be combined with what other medication to treat serious infections?

Answer 9

Vancomycin or beta-lactam

Question 10

Dosing considerations with Gentamicin?

Answer 10

• Reduce dose in patients with renal impairment.

- Adjust dose to achieve effective trough serum level.

Question 11

How is IV Gentamicin administered?

Answer 11

IV piggyback slowly (30 min or longer)

Question 12

What sx might indicate ototoxicity?

Answer 12

HA, tinnitus, hearing loss, nausea, dizziness, and vertigo

Question 13

What labs might indicate nephrotoxicity?

Answer 13

proteinuria, casts in the urine, dilute urine, elevated BUN, and elevated creatinine

Question 14

What sx can indicate nephrotoxicity?

Answer 14

hematuria, cloudy urine, oliguria/anuria

Question 15

Prototype for Sulfonamide combination?

Answer 15

Trimethoprim-sulfamethoxazole (Bactrim)

Question 16

Therapeutic use of Trimethoprim-sulfamethoxazole (Bactrim)?

Answer 16

bronchitis, shigella enteritis, OM, pneumocystis jirovecii pneumonia (PCP), UTI, Traveler’s diarrhea, prevention of PCP in HIV + patients

Question 17

MOA of Bactrim?

Answer 17

Bacteriostatic: combination inhibits the metabolism of folic acid in bacteria at two different points

Question 18

Adverse effects of Bactrim?

Answer 18

N/V, rash, phlebitis, ↑ K ↓Na, Steven-johnson syndrome, pseudomembranous colitis, several hematological effects

Question 19

Route, metabolism, and excretion of Bactrim?

Answer 19

Route: PO and IV; rapid onset
Metabolism: 20% liver
Excretion: active form via renal

Question 20

Contraindications for Bactrim?

Answer 20

hypersensitivity (sulfa allergy), History of sulfonamide- or trimethoprim-induced immune thrombocytopenia, megaloblastic anemia, infants <2 mos, severe hepatic or renal impairment, pregnancy

Question 21

Precautions with Bactrim?

Answer 21

mild to moderate hepatic or renal impairment and G6PD deficiency

Question 22

Interactions with Bactrim?

Answer 22

multiple drug interactions d/t inhibition of cytochrome P450

Question 23

Prototype for Fluoroquinolones?

Answer 23

Ciprofloxacin

Question 24

Therapeutic use of Cipro?

Answer 24

gram negative infections and some gram positive organisms

Question 25

MOA of Cipro?

Answer 25

bactericidal: inhibits bacterial DNA synthesis by inhibiting DNA enzyme

Question 26

Adverse effects of Cipro?

Answer 26

N/D, phlebitis at IV site, tendinitis, tendon rupture, photosensitivity, elevated ICP, seizures, hepatotoxicity, anaphylaxis, pseudomembranous colitis

Question 27

Cipro contraindications?

Answer 27

hypersensitivity, concurrent use of tizanidine

Question 28

Cipro precautions?

Answer 28

Known CNS disorders, renal impairment, hx of prolonged QT interval

Question 29

Cipro interactions?

Answer 29

can ↑ theophylline concentration, iron, multivitamins, calcium, magnesium, drugs that prolong the QT interval

Question 30

Route, metabolism, and excretion of Cipro?

Answer 30

Route: PO, PO-ER, and IV; rapid onset Metabolism: small amts in liver Excretion: 40-50% unchanged by kidney