Effect of Oxytetracycline and Tetracycline on Glucose Tolerance and Serum Lipids

Oxytetracycline or tetracycline, 10 mg/kg, was administered for 10 consecutive days to rabbits and rhesus monkeys. Glucose tolerance test was performed and different fractions of serum lipids were estimated in these animals before and after treatment with the antibiotics to find if their prolonged use interfered with carbohydrate and lipid metabolism. Both antibiotics diminished glucose tolerance. The pattern of serum lipids was changed. There were increases in the serum triglycerides, phospho-lipids, β-lipoprotein cholesterol and free fatty acids in most of the animals after treatment with the antibiotics. Tetracyclines should be used with caution due to the metabolic disturbances they might produce.