| toxicity summary | IDENTIFICATION AND USE: Flumequine is a fluoroquinolone compound with antimicrobial activity against Gram-negative organisms. It is used in the treatment of enteric infections in food animals and in the treatment of bacterial infections in farmed fish. Flumequine also has limited use in humans for the treatment of urinary tract infections. HUMAN EXPOSURE AND TOXICITY: Ocular side effects in 3 patients being treated with flumequine for urinary infections were reported. All 3 patients had chronic renal failure and all exhibited bilateral symmetry. Complete recovery occurred within 2 days of withdrawing the drug. ANIMAL STUDIES: Flumequine was administered by gastric tube to female mice for 14 days. No signs of alopecia or other toxicity were noted. Rats were orally administered flumequine for 14 days. Marked alopecia was observed in both sexes after 3 to 5 days treatment, which persisted for the duration of the study. In other study rats were orally administered flumequine for 14 days. Clinical signs included bloating, cyanosis, dehydration, reduced weight gain, and shedding. Guinea pigs were given oral doses of flumequine for 14 days. Mortality was noted. Beagle dogs were given daily oral doses of flumequine. All dogs survived the one-year treatment period. A decrease in food consumption was noted in all treatment groups throughout the study. A dose-dependent incidence of convulsive episodes was observed in treated dogs. The convulsions were relatively severe, of short duration , and almost always followed by ataxia and tremors. Normal behavior returned within about ten minutes after treatment. Other drug-related clinical signs observed included ataxia, hypoactivity, tremors, emesis, decreased food consumption, and body-weight loss. In an 18-month study, flumequine was administered in the feed to mice of each sex. A slight depression in body weight occurred in the high-dose group from the sixth week to termination of the study. Incidences of liver tumors seen grossly at necropsy were dose-related and more prevalent in males than in females. The incidence of hepatic toxic changes paralleled the liver tumor incidence. Chi-square analysis of the number of tumor-bearing animals indicated significant increases for the low- and high-dose males considering all tumors and benign tumors. The number of high-dose males with both benign and malignant liver tumors was also statistically significant. In females, the only significant increases occurred in the high-dose group for numbers of animals with any type or benign only tumors. In a 13-week study designed to investigate hepatotoxic lesions and the activities of hepatic drug-metabolizing enzymes, flumequine was administered to mice. The effects observed were reduced body weight, significantly increased plasma activities of alanine and aspartate aminotransferases, alkaline phosphatase and lactic dehydrogenase, and increased liver weights. Pregnant mice were orally administered flumequine from the second to fifteenth days of gestation. Incomplete ossification, invaginated trachea, dilatation of the renal pelvis, and cleft palate were observed in fetuses. These observations were interpreted as evidence of fetotoxic, not teratogenic, responses to exposure to flumequine. Pregnant rats were dosed orally with flumequine from the sixth through fifteenth days of gestation. There was a dose-related reduction of mean body weight in the treated dams and the difference from controls was significant at 400 mg/kg bw/day. The mean fetal weights of the mid- and high-dose groups were significantly lower as compared to controls. Dose-related incomplete ossification of sternebra, vertebrae, and skull bones were also noted in fetuses. No drug-related visceral or skeletal malformations were found and there was no embryotoxic effect noted in this study. Flumequine was negative in the following genotoxicity tests: Ames test, HGPRT test, Gene Mutation Assay and the Chromosome Aberration Assay. |