Toxicological evaluation of naringin: Acute, subchronic, and chronic toxicity in Beagle dogs.

Naringin is a type of bioflavonoid widely found in a lot of dietary products. Our previous studies revealed that naringin was practically non-toxic for SD rats in an oral acute toxicity study and the no-observed-adverse-effect-level (NOAEL) in SD rats was greater than 1250 mg/kg/day when administered by oral gavage for 13 consecutive weeks or 6 consecutive months. Herein we assessed the safety of naringin in Beagle dogs. Acute oral administration of naringin was done as a single bolus dose up to 5 g/kg. Subchronic toxicity study for 3 months and chronic toxicity study for 6 months were done by oral administration at doses of 0 (control), 20, 100, and 500 mg/kg. The LD50 dosage level for dogs was determined to be > 5 g/kg body weight. In the repeated-dose 3-month and 6-month oral toxicity studies, no morbidity, mortality, and toxicologically relevant events were observed either during dosing or the post-dosing recovery period. It was concluded that the NOAEL of naringin in Beagle dogs is at least 500 mg/kg body weight per day when administered orally for 3 and 6 consecutive months. These results, combined with the previous toxicological studies in rats, demonstrate a good safety profile of naringin.