Gaming addiction. Or psychiatrist?

Hi. My cousin who is around 17 yrs of age addicted to computer/mobile games/playstation. Since from his 6th grade, he was very adament and uninterested in studies. However, by his parents compulsion, he completed 10th std in 2016 with 80+ percentage. But after that he became very vigorous and addicted to computer games. He refused to go to school because of the same . His parents see lot of changes in his behavior. For ex, Getting extremely angry for small issues, Shouting, Breaking the objects at home,etc.  He even tried to stab his own brother for a small issue. As advised by one of the doctor, his parents taken him for consultation and admitted in hospital under certain medication and couselling/observation for 10 to 15 days. But still, no changes in his behaviour. Also, his hands are severing when he does some simple household works. Please suggest what should be done to change him to be on right path. His parents are worried. Should we take him to a psychologist or psychiatrist?