EE driving on site, fell asleep, hit guard rail, drove straight to Gate. Another EE was working gate. Area mgr & Ops. mgr. contacted. Area mgr. went on site. Ambulance called to check EE. EE did not want to go to hospital, changed mind, and decided to go; complaining of stomach pain. EE went hospital for evaluation. EE released with no restrictions on 10/28/2018.