Antibacterials - Aminoglycosides Flashcards
Aminoglycosides
Can cause C-diff and pseudomembranous colitis with extended use
Amikacin Usage
reatment of serious gram-negative bacilli bacteria that cause bone infections, respiratory tract infections, endocarditis, and septicemia that is resistant to gentamicin and tobramycin (for example: Pseudomonas, Proteus, Serratia)
Amikacin Dosage
Usual parenteral dose:
IM/IV: 5 to 7.5 mg/kg per dose every 8 hours
Amikacin Pearls
Low therapeutic index: individualize dosing
Use with caution if patient has low calcium
Monitor: urinalysis, blood urea nitrogen (BUN), serum creatinine (SCr), peaks and troughs (usually after third dose), vital signs, temperature, weight, input and output (I&O); audiograms at baseline, during, and after treatment if used for an extended period of time
Associated with:
Nephrotoxicity; use caution when using with other nephrotoxic agents
Neuromuscular blockade and paralysis; do not give after using anesthesia or a muscle relaxant
Neurotoxicity; ototoxicity can occur with high doses at extended use and is irreversible
Gentamicin Usage
Treatment of susceptible bacteria that cause bone infections, respiratory tract infections, skin and soft-tissue infections, abdominal and urinary tract infections, septicemia, and endocarditis (for example: Pseudomonas, Proteus, Serratia, Staphylococcus)
Gentamicin Dosage
Usual parenteral dose: IM/IV:
Conventional: 1 to 2.5 mg/kg per dose every 8 to 12 hours
Extended dosing interval: 4 to 7 mg/kg per dose once daily
Intrathecal: 4 to 8 mg per day
Gentamicin Pearls
May cause neuromuscular blockade and paralysis; do not give after using anesthesia or a muscle relaxant
Low therapeutic index: individualize dosing
Decreased absorption in atrophic muscles
Suitable solutions for administration are clear to slight yellow
Use with caution if patient has low calcium
Monitor: urinalysis, urine output, BUN, SCr, troughs and peaks (usually after third dose); audiograms at baseline, during, and after treatment if using for 2 weeks or more
Inconclusive data show certain penicillins, when administered with gentamicin, may result in loss of efficacy
Neomycin Usage
Portal-systemic encephalopathy as adjunct
Perioperative prophylaxis as adjunct with erythromycin
Neomycin Dosage
Usual oral dose for perioperative prophylaxis:
1 g at 1:00 pm, 2:00 pm, and 11:00 pm on the day before 8:00 am surgery as an adjunct
Usual oral dose for hepatic encephalopathy: 4 to 12 g daily in divided dose every 4 to 6 hours for 5 to 6 days
Chronic hepatic insufficiency:
4 g daily
Neomycin Pearls
Doses greater than 12 g per day may cause malabsorption of certain nutrients, fats, and glucose
Do not administer parenterally or as surgical irrigation due to toxicity from increased systemic absorption
Monitor: SCr and BUN at baseline and throughout therapy; audiograms if symptoms develop
Contraindicated in intestinal obstruction, inflammatory or ulcerative bowel disease
Associated with:
Nephrotoxicity; use caution when using with other nephrotoxic agents
Neuromuscular blockade and paralysis; do not give after using anesthesia or a muscle relaxant
Neurotoxicity; ototoxicity can occur with high doses at extended use and is irreversible
Streptomycin Usage
Treatment of tuberculosis in combination with other antibiotic agents
Treatment of numerous infections involving the following susceptible bacteria: plague (Yersinia pestis), tularemia (Francisella tularensis), Brucella, K. granulomatis, Haemophilus ducreyi, H. influenza, K. pneumoniae, E. coli, Proteus, E. aerogenes, E. faecalis, S. viridans, E. faecalis
Streptomycin Dosage
Usual parenteral dose:
IM: 15 to 30 mg/kg per day in divided doses or 1 to 2 g daily
Streptomycin Pearls
Adjusted doses for renal impairment are suggested, although the manufacturer does not provide specific dosing recommendations; refer to PI
Specific dosing recommendations for patients undergoing intermittent dialysis; refer to PI
Often used as second-line therapy due to the high risk of toxicities
Administer in mid lateral thigh muscle or upper gluteal muscle
Exposure to light can darken the solution without loss of efficacy
Monitor: audiograms at baseline and periodically during treatment; BUN, SCr, troughs and peaks after third dose
Associated with:
Nephrotoxicity; use caution when using with other nephrotoxic agents
Neuromuscular blockade and paralysis; do not give after using anesthesia or a muscle relaxant
Neurotoxicity; ototoxicity can occur with high doses at extended use and is irreversible
Parenteral infusions: need appropriate audiometric and laboratory testing facility in place
Tobramycin Usage
Treatment of infections by gram-negative bacilli
P. aeruginosa
Cystic fibrosis with P. aeruginosa
Treatment of susceptible bacteria that cause brucellosis, cholangitis, complicated diverticulitis, meningitis, pelvic inflammatory disease, plague (Yersinia pestis), pneumonia, tularemia, urinary tract infections, ocular infections
Prophylaxis against endocarditis
Tobramycin Dosage
Usual parenteral dose:
IM/IV: Conventional dosing: 1 to 2.5 mg/kg per dose every 8 to 12 hours
Extended interval dosing: 4 to 7 mg/kg per dose daily
Usual nebulized dose for cystic fibrosis:
300 mg of solution for inhalation nebulized every 12 hours in 28-day cycles
Usual oral inhalation dose for cystic fibrosis:
Powder for inhalation: 112 mg (four 28 mg capsules) every 12 hours in 28-day cycles
Usual ophthalmic dose:
Ointment: ½ inch, 2 to 6 times per day
Solution: 1 to 2 drops every 2 to 4 hours
