Tolmetin sodium is a non-steroidal anti-inflammatory drug (NSAID). Tolmetin sodium is an orally active and potent inhibitor of COX with IC 50s of 0.35 μM for human COX-1 and 0.82 μM for human COX-2, respectively [1] [2].

COX-1 (human):0.35 μM, COX-2 (human):0.82 μM

Tolmetin sodium at a concentration of 0.25 mM does not reduce lipid peroxidation in rat brain homogenate. However, Tolmetin at concentrations ranging from 0.25 to 1 mM exhibits antioxidant properties by scavenging free radicals, yet it does not induce the generation of superoxide anions in rat brain homogenate [3]. Additionally, Tolmetin sodium demonstrates dose-dependent anticancer effects against the HT-29 colon cancer cell line within the concentration range of 0.001-100 μM [4]. In contrast, concentrations of Tolmetin sodium up to 100 μM have no impact on the growth of osteoblasts [5].

Tolmetin sodium, administered at dosages of 30-100 mg/kg via gavage either as a single dose or twice daily for 3 and 14 days, exhibits its peak ulcerogenic effect in male Wistar rats (180-200 g) four hours post initial dose. This effect notably diminishes following repeated administration over 3 and 14 days. Furthermore, tolmetin is associated with gastric lesions at 100 mg/kg [2]. Pre-treatment with tolmetin sodium at 5 mg/kg, administered twice daily for 5 days, significantly mitigates quinolinic acid (QA)-induced neurotoxicity [3].