Nephro-hepatic Safety of Aqueous Justicia carnea Leaf Extract in Wistar Rats: A 14-Day Repeated-dose Oral Study

Background: Justicia carnea Lindl. (Acanthaceae) is widely consumed in Nigeria as a blood tonic, usually as a water-based preparation of the fresh leaves. Toxicological data on this preparation are scarce, and studies of alcoholic extracts have reported renal and hepatic changes at high doses. Aim: To determine whether repeated oral administration of the aqueous leaf extract alters serum markers of renal and hepatic function in healthy rats. Methods: Twenty-four male Wistar rats received distilled water (control, n = 4) or aqueous J. carnea leaf extract at 200, 400, 600 or 800 mg/kg body weight (n = 5 per group) by oral gavage once daily for 14 days. Serum from 14 rats (two or three per group) was analysed for urea, creatinine, sodium, potassium, chloride, bicarbonate, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and total and conjugated bilirubin. Groups were compared by one-way ANOVA with Dunnett’s test and by the Kruskal–Wallis test; effect sizes (Hedges’ g) and rank correlations with dose were calculated. Results: No deaths occurred. None of the markers differed significantly between groups (ANOVA p = 0.088–0.857). Creatinine was not elevated at any dose and showed a weak negative correlation with dose (Spearman’s ρ = −0.55, p = 0.043). AST and ALT were unchanged, and AST was lowest at 800 mg/kg. ALP was higher than control at 200–600 mg/kg (g = 0.70–1.41) but not at 800 mg/kg, without a dose trend or a rise in bilirubin. Bilirubin was unchanged. Conclusion: At 200–800 mg/kg for 14 days, the aqueous leaf extract produced no biochemical evidence of renal or hepatic injury in healthy rats. The aqueous preparation therefore appears to be safe for the kidney and liver at doses relevant to traditional use.