If it is your fault, you are responsible for all of his medical bills, lost wages, and pain and suffering. Without knowing the extent of his injuries, I cannot say how much this is. Depending on how the injury happened, you may have insurance that would cover this (for example if it was an automobile accident). Also, you say it was your fault. Usually this means you were negligent. If you were not negligent or did not breach some legal duty owed to the other party, you would not be responsible at all.
Answered on Dec 02nd, 2011 at 11:00 PM