Depending on how bad the wound is, a dog bite will take a different amount of time to recover. If you were bitten by a dog in the third degree, you might need to take antibiotics and wear a cast for several months. On the other hand, a first-degree dog bite might heal in a matter of days. Typically, it takes two weeks for dog bite wounds to heal. You must use an ice pack during this period to lessen pain and swelling.