Suggest Remedies For Vomiting And Abnormal Behavior After A Head Injury

good evening sir,

sir, my friend has got an injury in his head before two years back.
he had got severe internal pain in his head in that time. and now the problem is a little more serious . he is now constantly vomiting and has started behaving sometimes abnormal. so please suggest me that what kind of doctor i should consult.please help me by giving your kind suggestion