Abstract: Background and Objectives: There is a paucity of information about the penetration of antimicrobials in tonsils from pigs with the final goal to eradicate bacteria from this tissue where different microorganisms can survive for long periods of time. The objective of the study was to quantify The Tulathromycin (TT) penetration in tonsils after applying several TT regimen dosages as a first step to check the potential use of this molecule to eradicate bacteria from tonsils. Material and Methods: Animals were randomly divided in four groups (control, T1, T2 and T3) of ten animals in each one. T1, T2 and T3 group received a dose of 2.5, 5 and 7.5 mg of TT kg-1 body weight (bw) in one shot (Draxxin®), respectively and the control group received 2 mL of serum physiological. The animals were sacrificed by intravenous administration of pentobarbital sodium twenty four hours after finishing the treatment. Tonsils and blood samples were taken at necropsy to obtain serum. Results: The concentration in serum was always significantly lower (p<0.05) than in tonsil for the groups treated with TT. Average TT serum and tonsil concentrations increased significantly (p<0.05) in a dose-dependent fashion. Moreover, the tonsil TT versus serum TT concentration ratio was 5.4, 6.7 and 8.6 for the dose of 2.5, 5 and 7.5 mg kg-1, respectively. Conclusions: These results pave the way to use this antibiotic to eliminate bacteria from tonsils but additional studies are necessary to define correctly an administration schedule.