The idea of Internet addiction as a certifiable condition is gaining ground, with new research revealing the people who send excessive numbers of SMSs and e-mails could have a mental disorder. 

In the American Journal of Psychiatry, Jerald Block calls Internet addiction a common disorder and should be classified as a mental disorder.
He believes the fact that it is a mental condition is confirmed by users sufferering withdrawal symptoms that include anger and tension.
They also lose their sense of time when using their computer or cell phone.