Evaluation of Oxidative Stress Levels in Codeine-Induced and Codeine Recovery Phase of Albino Rats

The widespread availability and potential for misuse of codeine have rendered chronic use a pressing public health issue. Long-term codeine exposure can lead to multisystem toxicity, causing oxidative stress, cellular damage, and increased vulnerability to illness. This study assessed the levels of oxidative stress in Albino rats during the codeine-induced and codeine-recovery phases. For this study, 20 Albino rats weighing 160-200 g were used. The animals were assigned into four groups of five rats. Feed and water were administered to rats in Group 1 (control). Codeine was administered to Groups 2, 3, and 4 at doses of 10 mg/kg, 15 mg/kg, and 20 mg/kg body weight, respectively. Serum biochemical assays were conducted using blood samples collected on day 14. After that, the animals underwent a 7-day codeine withdrawal to assess recovery. Blood samples were collected on day 7 for the second phase of biochemical assay. Administration of codeine for 14 days significantly reduced antioxidant enzyme levels (superoxide dismutase, glutathione reductase, catalase, and glutathione peroxidase) (p < 0.05), but serum lipid peroxidation level was elevated (p < 0.05). After a 7-day recovery period, catalase, glutathione reductase, and glutathione peroxidase levels showed significant recovery (p < 0.05), lipid peroxidation decreased significantly (p < 0.05), but superoxide dismutase levels remained unchanged. These findings indicate that misuse of codeine adversely affects oxidative stress levels, persisting even after recovery. Therefore, caution is recommended when consuming codeine and other opioids.