Aim and Backround: Amytriptiline (AMY) a antidepressant used in the treatment of neuropathic pain. However
with limited therapeutic benefits and side effects of AMY is not helpful to majority of the neuropathic pain patients. Gallic
acid (GA) is a polyphenolic product with potential antioxidant effects and useful in neuropathic pain.
Objective: The purpose of the study was to investigate the improved neuropathic pain relief with GA in combination with
AMY in rats.
Methods: Partial sciatic nerve ligation (PSNL) method is used for neuropathic pain induction in rats. The rats were randomly
divided into 6 groups (n = 8), and treated with drugs or vehicle once daily for 15 days after the pain induction. The first
group was served as Normal control and received normal saline (p.o), second group was served as Sham Control and
received Normal Saline (p.o), third group served as Surgery Control, received normal saline (p.o), fourth group was received
with AMY (25mg/kg, p.o), fifth group was received with GA (100mg/kg,p.o), sixth group was received with both AMY
and GA. Further behavioural studies for pain were carried out on days 1,4,7,10,13,16,19 and 22. Histological studies of
sciatic nerves carried out on days 1, 15 and 22 and on 22nd day all the remaining animals were sacrificed for sciatic nerve
tissues biochemical estimations.
Results: GA attenuates neuropathic pain better in combination with AMY by ameliorating the behavioral, biochemical and
histopathological signs and symptoms. This effect resulting due to its antioxidant, antinociceptive and anti-inflammatory
actions. It also potentiates AMY antinociceptive and antioxidant effects when given in combination in a continuous
Conclusion: The results suggest that GA in combination with AMYattenuated the neuropathic pain. Hence, the use of GA
as an adjunctive with AMY in the neuropathic pain will be more therapeutically beneficial and further studies in patients
to confirm the results is warranted.