Background: Azithromycin (AZM) is used in periodontal infections. The present study compared gingival crevicular fluid concentration of azithromycin of two pharmaceutical companies through the HPLC method.

Methods: Two groups (n=15) of healthy volunteers participated in this study. The first group received an imported azithromycin (ImAZM) tablet (250 mg, PO) and the second group received an azithromycin tablet (250 mg PO) manufactured by an Iranian pharmaceutical company (IrAZM). Intrasulcular paper points (#30) were used in inter-proximal areas of molars and canines to collect gingival crevicular fluid samples at 6, 12, 36, 84 and 156 hours after drug administration.

Results: The maximum concentration of AZM in gingival crevicular fluid was detected in each group 36 hour after administration. The concentration levels for the participants receiving ImAZM and IrAZM were 14.38±5.75 and 12.64±3.53 ng/mL, respectively. The pharmacokinetic (PK) modeling data showed half-life of AZM was 107.47 hr & 91.42 hr while the clearance was 113.02 hr &119.0 hr for the group receiving ImAZM and IrAZM, respectively. No significant differences were observed in other PK parameters, areas under the concentration time curves for the groups were almost identical.

Conclusion: According to the results, there were no significant differences between the PK parameters of ImAZM and IrAZM products. It may be concluded that different doses of AZM have relatively similar PK parameters among the healthy participants.