From the Children's Physician Network
Establish a rule: "We never bite people."
Give the child a reason for the rule, namely that biting hurts.
Suggest a safe alternative behavior.
Tell the child that if he wants something he should come to you and ask for help or point to it. He should not bite the person who has it. If the child bites when he is angry, tell him, "If you are mad, come to me and tell me. Don’t bite anyone."
Interrupt biting with a sharp "No."
Be sure to use an unfriendly voice and look the child straight in the eye. Try to interrupt her when she looks as if she might bite someone before she actually does it. Especially close supervision of the child may be necessary until you are sure she will no longer bite people.
Give the child a time-out when he bites people.
Send him to a boring place for approximately one minute per year of age. If he tries to bite you while you are holding him, say "No." Always put him down immediately and walk away (a form of time-out). If time-out does not work, take away a favorite toy for the rest of the day.
Never bite a child for biting someone else.
Do not be a hypocrite and bite the child back, do not wash the child's mouth out with soap, do not spank. Eliminate all physical punishment and also eliminate "love-bites" because the child will not understand how they are different from painful biting.
Praise the child for not biting.
Praise the child especially when he is in situations in which he used to bite. Tell the child gently not to bite before you embark on a high-risk visit. Then if he doesn't bite, praise him afterward for good behavior.
Reference: Children's Physician Network