Side effects of cephalexin include nausea, vomiting, diarrhea and abdominal discomfort. Allergic reactions eg, skin rashes, urticaria, eosinophilia, angioedema and anaphylaxis may occur, and rises in liver enzyme values have been noted.
Neutropenia has been reported. Suprainfection with resistant microorganisms, particularly candida, may follow treatment. There is the possibility of development of pseudomembranous colitis.