Aminoglycosides

Aminoglycosides are a group of drugs that share chemical, antimicrobial, and pharmacological characteristics,as well as mechanism of action, metabolism and toxicity.

They do, however; differ in their clinical use. Refer to the Rat Medication Guide Index for individual drugs listed under Aminoglycosides.

This group of drugs are bactericidal against Gram-negative and some Gram-positive organisms as well as mycoplasma.

They are generally poorly absorbed after oral administration but do well when given parenterally. They cross the placental barrier and are moderately well distributed except for the central nervous system.

The aminoglycosides have the ability for causing ototoxicity, nephrotoxicity and neuromuscular blockade due to the potential for high serum and tissue concentrations, as well as if given for a prolonged period of time. This is especially prevalent when given by parenteral administration (e.g., IM, IV, SQ) due to systemic absorption. Studies have shown no evidence of toxicity when nebulized in therapeutic doses even with prolonged use. The lack of toxicity seen with nebulized aminoglycosides may be due to minimal or no systemic absorption, having lower unsustained serum concentrations due to a lower dosage used, and being directly delivered to the area of infection.

Finally, caution should be used when administering aminoglycosides in rats having renal insufficiency since excretion is primarily through glomerular filtration.