gentamicin

Question 1

what is gentamicin used for

Answer 1

it is an aminoglycoside antibiotic used for:

septicaemia
meningitis and other CNS infections
biliary-tract infection
acute pyelonephritis,
endocarditis, 
pneumonia in hospital patient
 prostatitis

Question 2

what are the contraindications for gentamicin

Answer 2

• via injection: myasthenia gravis

when used in the ear:

• patent grommet ( grommet is a tiny tube inserted into the eardrum to allow air to enter the middle ear)
• perforated tympanic membrane (burst ear drum)

Question 3

what are the cautions for gentamicin

Answer 3

dose related side effects, conditions with muscular weakness, correct dehydration before starting, Auditory disorder

Question 4

can gentamicin be given during pregnancy

Answer 4

avoid due to risk of auditory and vestibular

nerve damage in infant when used in second and third trimester

Question 5

what monitoring is needed for patients taking gentamicin

Answer 5

• serum concentration in renal impairment as drug excreted through the kidney
• auditory and vestibular function

Question 6

what is the ideal therapeutic range (dose) for gentamicin

Answer 6

• 5-10mg/L “peak”

- 2mg/L “trough”

Question 7

what are the symptoms of gentamicin toxicity

Answer 7

Nephrotoxicity and irreversible ototoxicity

Question 8

what is the risk when patients with mitochondrial mutations are given gentamicin

Answer 8

increased risk of deafness

Question 9

why should you monitor patients taking gentamicin for signs of histamine-related adverse reactions

Answer 9

some batches of gentamicin may contain higher than expected levels of histamine

Question 10

when should the Serum aminoglycoside concentration be measured for gentamicin

Answer 10

• after 3 or 4 doses of a multiple daily dose regimen

and

• after a dose change

Question 11

describe when the “peak” concentration of gentamicin is taken

Answer 11

approximately 1 hour after I.V/I.M administration

Question 12

describe when the “trough” concentration of gentamicin is taken

Answer 12

just before the next dose

also known as “pre-dose trough”

Question 13

what should you do if the PRE-DOSE (‘trough’) concentration of gentamicin is high

Answer 13

the interval between doses must be increased

Question 14

what should you do If the POST-DOSE (‘peak’) concentration is high

Answer 14

the dose must be decreased.