Tetracycline, oxytetracycline and doxycycline are the important tetracycline-class antibiotics used in veterinary medicine. The tetracyclines are bacteriostatic (they slow the growth of susceptible bacteria). They have anti-inflammatory properties as well. These drugs may be given by mouth, by injection, and by intravenous (IV) infusion. As with all medications, tetracycline antibiotics may produce side effects.
Tetracyclines can cause discoloration of the teeth and bones in young animals. This occurs because the drug concentrates in developing teeth and bones. The discoloration varies but may be grayish, brownish, or yellowish in color. For this reason, tetracyclines are not routinely given to young animals whose permanent teeth and bones are not fully developed. Generally, kittens and puppies may be given these antibiotics after six months of age.
I don't have any experience with puppies, but when I was in my early teens my dermatologist put me on tetracycline to help control acne. Later on, when I was in my 20's and had to have a wisdom tooth pulled, the dentist said, oh you must have been on tetracycline when you were young. He showed me my tooth he had just pulled, and it had a brown band around it.
