plazomicin

General

Pronunciation:
pla-zoe-mye-sin


Trade Name(s)

  • Zemdri

Ther. Class.

anti-infectives

Pharm. Class.

aminoglycosides

Indications

Complicated urinary tract infections, including pyelonephritis (should be reserved for patients who have limited or no alternative treatment options).

Action

Inhibits protein synthesis in bacteria by binding to the 30S ribosome.

Therapeutic Effect(s):

Bactericidal action (concentration-dependent).

Spectrum:

Active against gram-negative pathogens, including:

  • Escherichia coli,
  • Klebsiella pneumoniae,
  • Proteus mirabilis,
  • Enterobacter cloacae.

Pharmacokinetics

Absorption: IV administration results in complete bioavailability.

Distribution: Well distributed to tissues.

Metabolism and Excretion: Does not undergo metabolism. Primarily excreted by kidneys in urine (98% as unchanged drug).

Half-life: 3.5 hr (↑ in renal impairment).

TIME/ACTION PROFILE (plasma concentrations)

ROUTEONSETPEAKDURATION
IVrapid30 min24 hr

Contraindication/Precautions

Contraindicated in:

  • Hypersensitivity to any aminoglycoside;
  • OB:   Pregnancy.

Use Cautiously in:

  • Renal impairment (dose adjustments necessary; therapeutic drug monitoring useful in preventing nephrotoxicity and ototoxicity)
  • Hearing impairment
  • Neuromuscular diseases such as myasthenia gravis (↑ risk of muscle weakness exacerbation)
  • Lactation:  Use while breastfeeding only if potential maternal benefit justifies potential risk to infant;
  • Pedi:   Safety and effectiveness not established in children
  • Geri:   ↑ risk of renal impairment in older adults.

Adverse Reactions/Side Effects

CNS: headache

CV: hypertension, hypotension

EENT: ototoxicity (vestibular and cochlear)

GI: CLOSTRIDIOIDES DIFFICILE-ASSOCIATED DIARRHEA (CDAD), diarrhea, nausea, vomiting

GU: nephrotoxicity

Misc: HYPERSENSITIVITY REACTIONS (including anaphylaxis)

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

  • ↑ risk of nephrotoxicity when used with other  nephrotoxic drugs.
  • ↑ risk of delayed recovery of neuromuscular function when used with  neuromuscular blockers.

Route/Dosage

Estimate CCr with the Cockcroft-Gault formula using total body weight (TBW). For patients whose TBW is greater than their ideal body weight (IBW) by ≥25%, use IBW. Calculate dose using TBW. For patients whose TBW is greater than IBW by ≥25%, use adjusted body weight (IBW + 0.4 × [TBW-IBW]).

IV (Adults): 15 mg/kg every 24 hr for 4–7 days.

Renal Impairment 
IV (Adults): CCr 30–59 mL/min– 10 mg/kg every 24 hr for 4–7 days;  CCr 15–29 mL/min– 10 mg/kg every 48 hr for 4–7 days.

Availability

Solution for injection: 50 mg/mL

Assessment

  • Assess for infection (vital signs, urine, WBC) at beginning of and during therapy.
  • Obtain specimens for culture and sensitivity before initiating therapy. First dose may be given before receiving results.
  • Evaluate eighth cranial nerve function by audiometry before and throughout therapy. Hearing loss is usually in high-frequency range. Prompt recognition and intervention are essential in preventing permanent damage. Monitor for vestibular dysfunction (vertigo, ataxia, nausea, vomiting). Eighth cranial nerve dysfunction is associated with persistently elevated peak plazomicin levels. Discontinue plazomicin if tinnitus or subjective hearing loss occurs.
  • Monitor bowel function. Diarrhea, abdominal cramping, fever, and bloody stools should be reported to health care professional promptly as a sign of CDAD. May begin up to several wk following cessation of therapy.

  • Monitor intake and output and daily weight to assess hydration status and renal function.
  • Assess for signs of superinfection (fever, upper respiratory infection, vaginal itching or discharge, increasing malaise, diarrhea).
  • Monitor for signs and symptoms of hypersensitivity reactions (rash, pruritus, laryngeal edema, wheezing) during therapy.

Lab Test Considerations:

Monitor CCr prior to starting and daily during therapy.

Toxicity and Overdose:

Monitor blood levels periodically during therapy. Timing of blood levels is important in interpreting results. Draw trough levels within 30 min before infusion of 2nd dose. Extend dosing interval by 1.5 fold (i.e., from every 24 hr to every 36 hr or from every 48 hr to every 72 hr) for patients with plasma trough concentrations ≥3 mcg/mL.

Implementation

  • Intermittent Infusion:   Dilution:  Dilute solution in 0.9% NaCl or LR for a final volume of 50 mL.Solution is clear, colorless to yellow; do not infusion solutions that are cloudy, discolored or contain particulate matter. Diluted solution is stable at room temperature for 24 hr or 7 days if refrigerated at concentrations of 2.5 mg/mL to 45 mg/mL of 0.9% NaCl or LR.
  • Rate: Infuse over 30 min.
  • Y-Site Incompatibility: Do not mix with other drugs or infuse through same IV line.

Patient/Family Teaching

  • Explain purpose of plazomicin to patient. Emphasize importance of daily labs to prevent side effects.
  • Advise patient of the importance of drinking plenty of liquids.
  • Advise patient to notify health care professional immediately if signs and symptoms of hypersensitivity reaction (rash, hives, itching, swelling of lips, difficulty breathing) or if diarrhea, abdominal cramping, fever, or bloody stools occur. Instruct patient not to treat with antidiarrheals without consulting health care professional.

  • Advise patient to notify health care professional if changes in hearing or balance, or if new onset or changes in preexisting buzzing or roaring in ears occur, even if it occurs after the completion of therapy.
  • Advise patient to report the signs of superinfection (black, furry overgrowth on the tongue, vaginal itching or discharge, loose or foul-smelling stools).
  • Rep:  May cause fetal harm. Advise females of reproductive potential to use effective contraception during therapy. Advise patient to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes

Resolution of the signs and symptoms of infection. Length of time for complete resolution depends on the organism and site of infection.