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

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

Tolmetin sodium dihydrate at a concentration of 0.25 mM does not mitigate lipid peroxidation in rat brain homogenates. However, Tolmetin at varying concentrations (0.25, 0.5, 0.75, 1 mM) exhibits radical scavenging capabilities without generating superoxide anions in the same biological material [3]. At doses ranging from 0.001-100 μM, Tolmetin sodium dihydrate demonstrates dose-dependent anticancer properties against the HT-29 colon cancer cell line [4]. Yet, within the same concentration range (0-100 μM), it has no discernible impact on osteoblast growth [5].

Tolmetin sodium dihydrate, administered at doses of 30 and 100 mg/kg through gavage either as a single dose or twice daily for 3 and 14 days, demonstrated a peak ulcerogenic effect 4 hours post-single dose in male Wistar rats (180-200 g), which significantly diminished with continued administration over 3 and 14 days. Additionally, it caused gastric lesions at 100 mg/kg. Remarkably, a pre-treatment regimen of 5 mg/kg administered twice daily for 5 days effectively mitigated quinolinic acid (QA)-induced neurotoxicity.