Tobramycin

Sample material Serum or plasma. Serum and plasma samples of patients who receive penicillin or penicillin analogues besides the aminoglycoside cannot be stored for any prolonged period. In such cases the tobramycin concentration will drop. 

Specificity The drugs tabulated below produce a 15% increase in tobramycin concentration if added to a sample containing 4 mg/1 tobramycin, in a concen-  

The following drugs lead to a 25% increase in tobramycin concentration if they are added in the stated concentrations to a sample having a tobramycin concentration of 4 mg/1. 

References Packing leaflet LI 0339-H 12/86, ST15, ST34, ST42, ST82. 

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General Antibacterial Properties. In the clinical control of bacterial infectious disease, the aminoglycosides gentamicin, tobramycin, amikacin, netilmicin, and to a lesser extent, dibekacin and isepamicin are most commonly used for the treatment of serious infections involving aerobic or facultative gram-negative baciUi, especially in the compromised host. This usage is discussed in the Hterature (44—51). 

R = R = H) are intermediate, and gentamicin and tobramycin are most susceptible (66). Resistance to streptomycin is widespread, and its use is currently confined primarily to infections caused by Mycobacterium tuberculosis Yersiniapestis and Francisella tularensis. 

Drug resistance in the defined sense, however, is not always the reason for treatment failures. The formation of biofilms may be as well regarded as a resistance mechanism. Cells within such a film withstand the antibiotic treatment. Some antibiotics (e.g. the aminoglycoside tobramycin) penetrate only slowly into the film. A further explanation is the existence of cells living in a non-growing, protected phenotypic state. 

The aminoglycosides include amikacin (Amikin), gentamicin (Garamycin), kanamycin (Kantrex), neomycin (Mycifradin), netilmicin (Netromycin), streptomycin, and tobramycin (Nebcin). 

Which of the following complaints by a patient taking tobramycin would be most indicative the patient is experiencing ototoxicity ... 

A patient is prescribed 40 mg of tobramycin IM. Use the drug label shown below to determine die amount of drug to administer. The nurse would administer... 

Mr. Caravel, age 38 years, is prescribed tobramycin ophthalmic (Tobrex) for bacterial conjunctivitis. Discuss preadministration assessments the nurse would perform before instilling the drug. 

C ()Hi2N50(,P 60-92-4) see Bucladesine sodium adenosine triphosphate (CjoHifiNjOj P 56-65-5) see Tobramycin adiphenine... 

C, H37N50,o 4696-76-8) see Dibekacin Tobramycin bendazolic acid chloride (C 6H,3C1N202 40988-23-6) see Bendacort benzalacetone... 

An alternative approach was reported (49) in which tobramycin was directly incorporated into a porcine scleral shield with a 72-hr dissolution time by immersion in a solution of the drug. After implantation in rabbit eyes for up to 8 hr, the shields were removed and the concentration of antibiotic in the corneas and aqueous humor... 

The most important of these antibiotics are amikacin, tobramycin, netilmicin and especially gentamicin. 

To prevent development of resistance and promote synergy, inhaled tobramycin or colistin is usually added to an oral fluoroquinolone for P. aeruginosa coverage.1,3 Methicillin-sensitive S. aureus (MSSA) may be treated with oral amoxiciUin-clavulanic acid, dicloxacillin, first- or second-generation cephalosporins, trimethoprim-sulfamethoxazole, or clindamycin, depending on sensitivity. Likewise, methiciUin-resistant S. aureus (MRSA) may be treated with oral trimethoprim-sulfamethoxazole, clindamycin, minocycline, or linezolid. H. influenzae often produces... 

Tobramycin, gentamicin Amikacin Vancomycin 10-12 30-40 C Less than 1.5 Less than 5.0 10-15 21.4-25.7 35.1-46.8 C Less than 3.2 Less than 5.85 7-10.35... 

Inhaled tobramycin (TOBI ) is typically administered to patients 6 years of age and older in alternating 28-day cycles of 300 mg nebulized twice daily, followed by a 28-day washout or off period to minimize development of resistance. Longterm intermittent administration improves pulmonary function, decreases microbial burden, and reduces the need for hospitalization for IV therapy.24,25 Due to minimal systemic absorption, pharmacokinetic monitoring is not necessary with normal renal function. Lower doses of nebulized tobramycin solution for injection have been used in younger children, and studies are underway using 300 mg twice daily in children under age 6. 

Nebulized colistin using the IV formulation may be an option in patients with tobramycin-resistant strains or intolerance to inhaled tobramycin. Due to an increased risk of bronchoconstriction after colistin inhalation, patients should pre-treat with albuterol and administer the first doses under medical observation.1,5... 

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