Two studies have been performed to assess the relative bioavailability of Azomycin (Julphar, UAE) as compared with Zithromax (Pfizer, USA) at the International Pharmaceutical Research Center (IPRC), Amman, Jordan. One study involved Azomycin capsules and the other Azomycin suspension. Each study enrolled 24 volunteers and in both studies, after an overnight fasting, the two brands of azithromycin were administered as single dose on two treatment days separated by a 2 weeks washout period. After dosing, serial blood samples were collected for a period of 192 h. Plasma harvested from blood, was analysed for azithromycin by HPLC coupled with electrochemical detection. Various pharmacokinetic parameters including AUC(0-t,) AUC(0-infinity,) C(max), T(max), T(1/2) and K(elm) were determined from plasma concentrations for both formulations and found to be in good agreement with the reported values. AUC(0-t), AUC(0-infinity) and C(max) were tested for bioequivalence after log-transformation of data. No significant difference was found based on ANOVA; 90% confidence intervals for the test/reference ratios of these parameters were found within the bioequivalence acceptance range of 80-125%. Based on these statistical inferences it was concluded that Azomycin capsule is bioequivalent to Zithromax capsule and Azomycin suspension is bioequivalent to Zithromax suspension.