© 2020 The Author(s) Piroxicam (PM) is an oxicam-NSAID commonly recommended for various pain and associated inflammatory disorders. However, it is reported to have a gastric and hepato-renal toxic effect. Therefore, the current research was planned to investigate the possible mechanisms behind the mitigating action of the coenzyme (CoQ10), a natural, free radical scavenger, against PM tissue injury. Rats were assigned to five equal groups; Control, CoQ10 (10 mg/kg, orally), PM (7 mg/kg, i.p.), CoQ + PM L, and CoQ + PM H group. After 28 days, PM provoked severe gastric ulceration and marked liver and kidney damage indicated by an elevated gastric ulcer index and considerable alteration in liver and kidney biochemical tests. The toxic effects might be attributed to mitochondrial dysfunction and excess generation of reactive oxygen species (ROS), as indicated by enhanced malondialdehyde (MDA) levels along with decreased reduced-glutathione (GSH) levels and catalase (CAT) activity. Apoptotic cell death also was demonstrated by increased regulation of activated caspase-3 in the stomach, liver, and kidney tissues. Interestingly, external supplementation of CoQ10 attenuated the PM-inflicted deleterious oxidative harm and apoptosis. This ameliorative action was ascribed to the free radical scavenging activity of CoQ10.