Gentamicin sulfate

Jan 5
16:00

2010

 michael

michael

  • Share this article on Facebook
  • Share this article on Twitter
  • Share this article on Linkedin

Serious infections due to sensitive strains of Pseudomonas aeruginosa, Escherichia coli, Proteus, Klebsiella, Serratia, Enterobacter, Citrobacter, or Staphylococcus Adults: 3 mg/kg daily in divided doses I.M. or I.V. infusion q 8 hours. For life threatening infections, patient may receive up to 5 mg/kg daily in three to four divided doses; dose should be reduced to 3 mg/kg daily as soon as clinically indicated.

mediaimage
HOW SUPPLIED

Injection: 40 mg/ml (adult),Gentamicin sulfate Articles 10 mg/ml (pediatric)

I. V. infusion (premixed): 40 mg, 60 mg, 70 mg, 80 mg, 90 mg, 100 mg, 120 mg in normal saline solution

ACTION

Inhibits protein synthesis by binding directly to the 30S ribosomal subunit. Usually bactericidal.

INDICATIONS & DOSAGE

Children: 2 to 2.5 mg/kg q 8 hours I.M. or by I. V. infusion.

Neonates over age 1 week or infants: 2.5 mg/kg q 8 hours I.M. or by I. V. infusion.

Neonates under age 1 week and pretenn infants: 2.5 mg/kg q 12 hours I.M. or by I.V. infusion.

Meningitis -

Adults: systemic therapy as above.

Children: systemic therapy as above.

Endocarditis prophylaxis for GI or GU procedure or surgery-

Adults: 1.5 mg/kg LM. or LV. 30 minutes before procedure or surgery. Maximum dose is 80 mg. Given with ampicillin (vancomycin in penicillinallergic patients).

Children: 2 mg/kg LM. or I.V. 30 minutes before procedure or surgery. Maxi­mum dose is 80 mg. Given with ampicillin (vancomycin in penicillin allergic patients).

After hemodialysis to maintain thera­peutic blood levels -

Adults: 1 to 1.7 mg/kg I.M. or by LV. inusion after each dialysis.

Children: 2 to 2.5 mg/kg LM. or by 1. V. infusion after each dialysis.

Dosage adjustment: For adult patients with impaired renal function, doses and frequency are determined by serum gentamicin levels and renal function.

ADVERSE REACTIONS

CNS: headache, lethargy, encephalopathy, confusion, dizziness, seizures, numb­ness, peripheral neuropathy, vertigo, ataxia, tingling.

CV: hypotension.

EENT: ototoxicity, blurred vision, tinnitus.

GI: vomiting, nausea.

GU: nephrotoxicity; possible elevation in BUN, nonprotein nitrogen, or serum cre­atinine levels; possible increase in urinary excretion of casts.

Hematologic: anemia, eosinophilia, leukopenia, thrombocytopenia, agranulocytosis.

Hepatic: increased ALT, AST, bilirubin, LD.

Musculoskeletal: muscle twitching, myasthenia gravis-like syndrome.

Respiratory: apnea.

Skin: rash, urticaria, pruritus.

Other: fever, anaphylaxis; injection site pain.

INTERACTIONS

Drug-drug. Acyclovir, amphotericin B, cisplatin, methoxyflurane, vancomycin, other aminoglycosides: increased ototoxicity and nephrotoxicity. Use together cautiously.

Cephalosporins: increased nephrotoxicity. Use together cautiously. Dimenhydrinate: may mask symptoms of ototoxicity. Use with caution.

General anesthetics, neuromuscular blockers: may potentiate neuromuscular blockade. Monitor closely.

Indomethacin: may increase serum peak and trough levels of gentamicin. Serum gentamicin ]evels must be monitored closely.

I. V. loop diuretics (such as furosemide): increased ototoxicity. Use cautiously. Parenteral penicillins (such as ampicillin and ticarcillin): gentamicin inactivation in vitro. Don't mix together.

EFFECTS ON DIAGNOSTIC TESTS

None reported.

CONTRAINDICATIONS

Contraindicated in hypersensitivity to drug or other aminoglycosides

SPECIAL CONSIDERATIONS

" Use cautiously in neonates, infants, elderly patients, and patients with impaired renal function or neuromuscular disorders.

" A specimen for culture and sensitivity tests is obtained before first dose is given.

" Patient's hearing must be evaluated before and during therapy. Patient complaints of tinnitus, vertigo, or hearing loss are important.

" Patient's weight and renal function studies must be reviewed before therapy begins.

" Alert: Preservative-free formulations of gentamicin are used when the intrathecal route is ordered.

" Blood for peak gentamicin level is obtained I hour after I.M. injection or 30 minutes after LV. infusion finishes; for trough levels, blood is drawn just before next dose. Blood must not be collected in a heparinized tube; heparin is incompatible with aminoglycosides.

" Peak blood levels over 10 mcg/ml and trough levels over 2 mcg/m] may be associated with higher incidence of toxicity.

" Urine output, specific gravity, urina]y­sis, BUN and creatinine levels, and crea­tinine clearance must be monitored.

" Hemodialysis for 8 hours removes up to 50% of drug from blood.

" Superinfection (continued fever and other signs and symptoms of new infection, especially of upper respiratory tract) may occur.

" Therapy usually continues for 7 to 10 days. If no response occurs in 3 to 5 days, therapy may be stopped and new specimens obtained for culture and sensitivity testing.

I. V. administration

" When giving by intermittent LV. infusion, the drug is diluted with 50 to 200 ml of Ds W or normal saline injection and infused over 30 minutes to 2 hours. After completing LV. infusion, the line is flushed with normal saline solution or Ds W.

Patient teathing

" Maintain adequate fluid intake and report adverse reactions promptly.

" Don't perform hazardous activities if adverse CNS reactions occur.