Vancomycin drug monitoring

Freeman CD, Quintiliani R, Nightingale CH. Vancomycin therapeutic drug monitoring is it necessary Ann Pharmacother 1993 27(5) 594-8. 

Pharmacokinetics of vancomycin Renal transport of vancomycin Epidemiology of vancomycin nephrotoxicity Risk factors for nephrotoxicity Therapeutic drug monitoring of vancomycin Prevention of vancomycin nephrotoxicity Alternative gram positive antibiotics References ... 

Due to the risks of serious adverse events such as nephrotoxicity and ototoxicity observed when systemic vancomycin was first used, therapeutic drug monitoring programs (TDM) for vancomycin were developed. To amehorate the risk of toxicity, clinicians have historically targeted a peak vancomycin serum concentration of 30 to 40 mg/L and a trough serum concentration of 5 to 10 mg/L. However, there is a notable lack of... 

Welty TE, Copa AK, Impact of vancomycin therapeutic drug monitoring on patient care, Ann of Pharmacother, 1994,28 1335-39. 

Ceftriaxone and vancomycin are the agents of choice to treat presumed pneumococcal meningitis empirically until the susceptibility is known. Penicillin may be used for drug-susceptible isolates with MICs of 0.06 mg/L or less, but for intermediate isolates, ceftriaxone is used, and for highly drug resistant isolates, a combination of ceftriaxone and vancomycin should be used. Vancomycin should not be used as monotherapy. In especially severe cases, therapeutic drug monitoring of the CSF and possibly even direct antibiotic instillation may be necessary. 

After administering vancomycin, monitor the patient s renal function to assure there is adequate volume to excrete vancomycin. Also monitor the patient s white blood cell count to determine if the drug is effective. 

The nurse should administer each IV dose of vancomycin over 60 minutes Too rapid an infusion may result in a sudden and profound fall in blood pressure and shock. When giving the drug IV, the nurse closely monitors the infusion rate and the patient s blood pressure. The nurse reports any decrease in blood pressure or reports of throbbing neck or back pain. These symptoms could indicate a severe adverse reaction referred to as "red neck or "red man syndrome. 9/mptoms of this syndrome include a sudden and profound fall in blood pressure, fever, chills paresthesias and erythema (redness) of the neck and badk. 

Gentamicin is an aminoglycoside. All aminoglycosides tend to be nephrotoxic and ototoxic. The dose must be reduced and serum concentrations must be monitored in patients with impaired renal function. Concomitant administration of aminoglycosides and other nephrotoxic drugs, such as certain diuretics, ciclosporin, teicoplanin and vancomycin should be avoided. 

WARNING Renal impair is the major tox foUow administration instructions Uses CMV retinitis w/ HIV Action Selective inhibition of viral DNA synth Dose Rx 5 mg/kg IV over 1 h once/wk for 2 wk w/ probenecid Maint 5 mg/kg IV once/2 wk w/ probenecid (2 g PO 3 h prior to cidofovir, then 1 g PO at 2 h 8 h after cidofovir) X in renal impair Caution [C, -] Contra Probenecid or sulfa allergy Disp Inj SE Renal tox, chills, fever, HA, NA /D, thrombocytopenia, neutropenia Interactions t Nephrotox W/ aminoglycosides, amphot icin B, foscar-net, IV pentamidine, NSAIDs, vancomycin t effects W/zidovudine EMS Monitor ECG for hypocalcemia (t QT int val) and hypokalemia (flattened T waves) OD May cause renal failure hydration may be effective in reducing drug levels/effects Cilostazol (Pletal) TAntiplatelet, Arterial Vasodilator/ Phosphodiesterase Inhibitor] Uses Reduce Sxs of intermittent claudication Action Phosphodiesterase in inhibitor t s cAMP in pits blood vessels, vasodilation inhibit pit aggregation Dose 100 mg PO bid, 1/2 h before or 2 h after breakfast dinner Caution [C, +/-] Contra CHE, hemostatic disorders. 

ADEFOVIR DIPIVOXIL 1. ANTIBIOTICS -aminoglycosides, vancomycin 2. ANTICANCER AND IMMUNOMODULATING DRUGS - cidosporin, tacrolimus 3. ANTIFUNGALS-amphotericin, 4. ANTIPROTOZOALS-pentamidine 5. ANTIVIRALS - cidofovir, foscarnet sodium, tenofovir Possible t efficacy and side-effects Competition for renal excretion Monitor renal function weekly... 

Vancomycin exhibits predictable pharmacokinetic properties and its clinical use has been guided by the pharmacokinetic monitoring of serum levels to determine the dose and frequency of administration. Pharmacokinetic monitoring of vancomycin, however, has become increasingly controversial given the improved safety of this antibiotic and the lack of data to support what are considered the therapeutic and toxic serum levels. Historically, the most severe toxicities of vancomycin were ototoxicity and nephrotoxicity. The incidence of nephrotoxicity has declined since its introduction possibly due to the availability of purer forms of the antibiotic. Ototoxicity has always been a rare adverse event of vancomycin, but it has been observed with excessively high concentrations of the drug in plasma [170-172]. The purpose of this section is to describe the nephrotoxicity associated with the clinical use of vancomycin. 

Serum drug concentrations should be monitored for drugs with narrow therapeutic indices and ehminated largely by the kidney (e.g., aminoglycosides and vancomycin) to optimize therapy in pediatric patients with renal dysfunction. For drugs with wide therapeutic ranges (e.g., penicillins and cephalosporins), dosage adjustment may be necessary only in moderate to severe renal failure. 

Vancomycin hydrochloride 30 mg/kg per 24 h IV in two equally divided doses, not to exceed 2 g/24 h unless serum levels are monitored 4 Vancomycin therapy is recommended for patients allergic to yfi-lactams (see text regarding drug levels) according to the guidelines, serum concentrations of vancomycin should be obtained 1 h after completion of the infusion and should be in the range of 30-45 mcg/mL for twice-daily dosing... 

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