After the administration of Duphamox, amoxicillin is absorbed and widely distributed in the body and high levels are found in kidney, urine, liver and bile. Amoxicillin has a rapid bactericidal action which normally prevents the recrudescence of respiratory infections. As with other penicillins, absence of toxicity is normally encountered. Animals with functional rumens should only be treated parenterally.
It is not generally recommended to use bactericidal and bacteriostatic antibiotics at the same time.
Beta-lactam antibiotics are known to interact with antibiotics with bacteriostatic action such as chloramphenicol, macrolides, sulfonamides and tetracyclines. There is also synergic action of penicillins with aminoglycosides.