O-3-amino-3-deoxy-α-D-glucopyranosyl-(1->6)-O-[ 2,6-diamino-2,3,6-trideoxy-α-D-ribohexopyranosyl-(1->4)]-2-deoxy-D-streptamine
Empirical Formula: C18H37N5O9
Molecular Weight: 467.54
Appearance: white to off-white powder
Hydroscopic
Freely soluble in water, slightly soluble in alcohol
Tobramycin is an aminoglycoside antibiotic complex produced by cultures of streptomyces tenebrarius, most commonly formulated as a sulfate salt. Common formulations include sterile powder, aqueous solutions for intravenous or intramuscular administration, aqueous solution for inhalation, ophthamalic ointment, and ophthamalic suspension. Tobramycin is effective against many aerobic gram negative bacteria, including pseudomonas aeruginosa (commonly found in the lungs of cystic fibrosis patients), and some aerobic gram positive bacteria, including staphylococcus aureus. Like most aminoglycosides, tobramycin is not very effective against streptococci, and most enterococci strains are resistant. Long-term use of tobramycin can cause renal toxicity, typically reversible if treatment is discontinued. Tinnitus and hearing loss can also occur; hearing impairment is permanent in some cases.
Sources:
Merck Index
USP24/NF19
American Hospital Formulary Service Drug Information