the objective of the present study was to characterize the essential oil of myrciaria tenella (mteo) leaves, to determine the effects of distillation time (1 to 5 h), and to evaluate its action on acute pain and inflammation both in vivo and in vitro. mteo was obtained by hydrodistillation for 4 h and 36 compounds were detected, mainly consisting of hydrocarbon terpenes such as -pinene (21.46%), -pinene (19.43%), e-caryophyllene (10.89%) and aromadendrene (9.17%). a high yield of -pinene/-pinene-rich mteo was obtained after only 2 h of extraction. for in vivo biological assays, mteo was administered to male swiss mice, showing an action against hypernociception (acetic acid-induced abdominal writhing, formalin and von frey models) and inhibiting carrageenan-induced paw edema. production of il-6, tnf-, il-1, pge2 was reduced and production of il-10 was increased, with no change in motor performance. mteo also reduced cell production of no and cytokines, in addition to inhibiting cox activity.