Determination of the bioavailability of gentamicin to the lungs following inhalation from two jet nebulizers.
OBJECTIVE
To determine the bioavailability of gentamicin to the lung following inhalation from two jet nebulizers.


METHODS
Serial urine samples were obtained from 10 volunteers after a 80 mg dose given orally, nebulized from a Pari LC + (PARI) and MicroNeb III (MN) devices, or after a 40 mg intravenous dose. In vitro aerodynamic characteristics of the nebulized doses were also determined.


RESULTS
The mean (SD) absolute gentamicin lung bioavailalibility following delivery by PARI and MN devices was 1.4 (0.4) and 1.7 (0.5) %. The mass median aerodynamic diameter (MMAD) of the drug particles from the PARI and MN systems was 8.6 (0.6) and 6.7 (0.5) microm and the corresponding fine particle doses (FPD) were 10.2 (2.8) and 11.7 (1.5) mg.


CONCLUSIONS
The MMAD and FPD data reflect the poor lung deposition of gentamicin identified by urinary excretion.
Al-Amoud
A I
AI
School of Pharmacy, University of Bradford, Bradford BD7 1DP, UK.
Clark
B J
BJ
Assi
K A
KA
Chrystyn
H
H
D000280:Administration, Inhalation; D000284:Administration, Oral; D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000652:urine; D001682:Biological Availability; D005260:Female; D005839:Gentamicins / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000652:urine; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008297:Male; D009330:Nebulizers and Vaporizers
D000900:Anti-Bacterial Agents; D005839:Gentamicins