Question

Tobramycin is an effective bactericidal in the plasma concentration range 4–8 mcg/mL to most Gram-negative organisms. Simon et al. (Antimicrob Agents Chemother 1973; 3: 445) reported the elimination half life and the volume of distribution of tobramycin to be 1.60 h and 0.241 L/ kg, respectively. If 3 mL (60 mg/1.5 mL) of tobramycin is administered as an intravenous bolus to a normal healthy subject (66.666 kg weight), what will be the duration of action for the administered dose?

Answer 1

Duration of drug action depends on several factors such as ,the absolute amount of drug given,the pharmaceutical preparation,the reversibilty of drug action,the half life of the drug,the activity of metabolites,influence of the disease on drugg elimination,etc

Tobramycin 1mg/kg body weight usually persists for 8 hours in te plasma.

Usually Tobramycin given in devided doses except for Severe UTI to avoid plasma concentration reach more than 12mcg/ml, which is a fatal condition.The action of drug starts immediately after IV infusion.