amikacin sulfate

Drug Name

Generic Name: amikacin sulfate Brand Name: Amikin Classifications: Anti-infective; Aminoglycoside Pregnancy Category: C

Availability

• 250 mg/mL, 50 mg/mL injection

Actions

• Semisynthetic derivative of kanamycin with broad range of antimicrobial activity that includes many strains resistant to other aminoglycosides.
• Pharmacologic properties are essentially the same as those of gentamicin.
• Appears to inhibit protein synthesis in bacterial cell and is usually bactericidal.

Therapeutic Effects

• Effective against a wide variety of gram-negative bacteria including Escherichia coli, Enterobacter, Klebsiella pneumoniae, most strains of Pseudomonas aeruginosa, and many strains of Proteus species, Serratia, Providencia stuartii, Citrobacter freundii, Acinetobacter. Also effective against penicillinase- and non-penicillinase-producing Staphylococcus species, and against Mycobacterium tuberculosis and atypical mycobacteria.

Uses

• Primarily for short-term treatment of serious infections of respiratory tract, bones, joints, skin, and soft tissue, CNS (including meningitis), peritonitis burns, recurrent urinary tract infections (UTIs).
• Unlabeled Uses: Intrathecal or intraventricular administration, in conjunction with IM or IV dosage.

Contraindications

• History of hypersensitivity or toxic reaction with an aminoglycoside antibiotic.
• Safety during pregnancy (category C), lactation, neonates and infants, or use period exceeding 14 years old is not established.

Cautious Use

• Impaired renal function; eighth cranial (auditory) nerve impairment; preexisting vertigo or dizziness, tinnitus, or dehydration; fever; older adults, premature infants, neonates and infants; myasthenia gravis; parkinsonism; hypocalcemia.

Route & Dosage

Moderate to Severe Infections

• Adult: IV/IM 5–7.5 mg/kg loading dose, then 7.5 mg/kg q12h
• Child: IV/IM 5–7.5 mg/kg loading dose, then 5 mg/kg q8h or 7.5 mg/kg q12h
• Neonate: IV/IM 10 mg/kg loading dose, then 7.5 mg/kg q12–24h

Uncomplicated UTI

• Adult: IV/IM 250 mg q12h

Administration

Intramuscular

• Use the 250 mg/mL vials for IM injection. Calculate the required dose and withdraw the equivalent number of mLs from the vial.
• Give deep IM into a large muscle.

Intravenous

• Verify correct IV concentration and rate of infusion with physician for neonates, infants, and children.

Adverse Effects

• CNS: Neurotoxicity: drowsiness, unsteady gait, weakness, clumsiness, paresthesias, tremors, convulsions, peripheral neuritis.
• Special Senses: Auditory–ototoxicity, high-frequency hearing loss, complete hearing loss (occasionally permanent); tinnitus; ringing or buzzing in ears;
• Vestibular: dizziness, ataxia.
• GI: Nausea, vomiting, hepatotoxicity.
• Metabolic: Hypokalemia, hypomagnesemia.
• Skin: Skin rash, urticaria, pruritus, redness.
• Urogenital: Oliguria, urinary frequency, hematuria, tubular necrosis, azotemia.
• Other: Superinfections.

Interactions

• Drug: ANESTHETICS, SKELETAL MUSCLE RELAXANTS have additive neuromuscular blocking effects; acyclovir, amphotericin B, bacitracin, capreomycin, cephalosporins, colistin, cisplatin, carboplatin, methoxyflurane, polymyxin B, vancomycin, furosemide, ethacrynic acid increase risk of ototoxicity and nephrotoxicity.

Pharmacokinetics

• Peak: 30 min IV; 45 min to 2 h IM.
• Distribution: Does not cross blood–brain barrier; crosses placenta; accumulates in renal cortex.
• Elimination: 94%–98% excreted renally in 24 h, remainder in 10–30 d.
• Half-Life: 2–3 h in adults, 4–8 h in neonates.

Nursing Considerations

Assessment & Drug Effects

• Baseline tests: Before initial dose, C&S; renal function and vestibulocochlear nerve function (and at regular intervals during therapy; closely monitor in the older adult, patients with documented ear problems, renal impairment, or during high dose or prolonged therapy).
• Monitor peak and trough amikacin blood levels: Draw blood 1 h after IM or immediately after completion of IV infusion; draw trough levels immediately before the next IM or IV dose.
• Lab tests: Periodic serum creatinine and BUN, complete urinalysis. With treatment over 10 d, daily tests of renal function, weekly audiograms, and vestibular tests are strongly advised.
• Monitor serum creatinine or creatinine clearance (generally preferred) more often, in the presence of impaired renal function, in neonates, and in the older adult; note that prolonged high trough (>8 mg/mL) or peak (>30–35 mg/mL) levels are associated with toxicity.
• Monitor S&S of ototoxicity (primarily involves the cochlear (auditory) branch; high-frequency deafness usually appears first and can be detected only by audiometer); indicators of declining renal function; respiratory tract infections and other symptoms indicative of superinfections and notify physician should they occur.
• Monitor for and report auditory symptoms (tinnitus, roaring noises, sensation of fullness in ears, hearing loss) and vestibular disturbances (dizziness or vertigo, nystagmus, ataxia).
• Monitor & report any changes in I&O, oliguria, hematuria, or cloudy urine. Keeping patient well hydrated reduces risk of nephrotoxicity; consult physician regarding optimum fluid intake.

Patient & Family Education

• Report immediately any changes in hearing or unexplained ringing/roaring noises or dizziness, and problems with balance or coordination.
• Do not breast feed while taking this drug without consulting physician.

Posted in: Pharmacology