Aminoglycosides

Question 1

Mode of action

Answer 1

Inhibits bacterial protein synthesis

Requires oxygen-dependent transport mechanism to enter bacteria (ineffective against anaerobic)

Bind to 30s subunit of bacterial ribosome

1. Interfere with the initiation complex of peptide formation
2. Induce mis-reading of mRNA
3. Break up polysomes

Question 2

Uses

Answer 2

Gram negative sepsis (hydrophilic so remains in bloodstream, tobramycin used for pseudomonal infections, UTI treatment

Question 3

Pharmacokinetics

Answer 3

Highly polar, eliminated by kidney (T1/2 2-3 hours), elimination mirrors eGFR, must reduce dose and frequency in renal impairment

Question 4

Adverse effects

Answer 4

Ototoxicity, nephrotoxicity, narrow therapeutic window

Question 5

Monitoring

Answer 5

Measure serum trough levels after 1st dose
Peak 5-10mg/L (3-5mg/L if tds)
Trough