Veterinary medicines, especially antibiotics, are among the most important components related to animal feed production. Generally, the main use of antibiotics in animals is for the treatment and prevention of diseases and growth promotion. Antibiotic usage in animals may result antibiotic residues in foodstuffs such as milk, egg and meat. These residues may cause various side effects such as transfer of antibiotic resistant bacteria to humans, immunopathological effects, allergy, mutagenicity, nephropathy (gentamicin), hepatotoxicity, reproductive disorders, bone marrow toxicity (chloramphenicol) and even carcinogenicity (sulphamethazine, oxytetracycline, furazolidone). The most important adverse effect of antibiotic residues is the transfer or antibiotic resistant bacteria to the humans due to the mobile properties of resistance. Because of these undesirable effects, it is important to regulate the use of antibiotics in food animals. The individuals and the local procedures should be aware of the problem through education by authorities. In this review, antibiotic use in the foodstuffs and their effects on the human health will be discussed.