Abstract:

The pharmacokinetics and relative bioavailability of a sustained-release capsule of albuterol (Salbuta) made by CDDA (China) were investigated following a single and multiple oral dose given to 20 healthy male volunteers in a randomized 2-way cross-over study. The controlled-release tablet of albuterol (Volmax) made by Glaxo (U.K.) was used as reference preparation. Plasma concentration of albuterol was determined by a newly developed HPLC method with UV detection. After a single oral dose the peak concentrations Cmax were 10.6±3.94 ng·mL^-1 and 10.52±2.59 ng·mL^-1 at 5.50±0.85 h and 5.30±0.95 h and the AUC0-∞ were 124.74±33.86 h·ng·mL^-1 and 126.02±38. 17 h.ng·mL-1 for Salbuta and Volmax respectively. The relative bioavailability of Salbuta was 98.98±12.04%. Following multiple dosing, mean steady state C^ssmax values were 12.94±3.35 ng·mL^-1 and 12.60±3.36 ng.mL^-1, mean C^ssmin values were 5.84±1.34 ng.mL^-1 and 6.16±1.33 ng·mL^-1, the degree of fluctuation (DF) was 81.82±17.74% and 76.03±20.48% for the two formulations respectively. The results of statistical comparison showed that the two preparations were bioequivalent.

Key words: Albuterol, Albuterol, Pharmacokinetics, Pharmacokinetics, Bioavailability, Bioavailability, HPLC, HPLC