Roy Patten, 39, who comes from Hyde in Greater Manchester,Â was last seen more than a week ago and police think he may have travelled to London via Doncaster.
He was last seen at around 8:15pm on Sunday 2 September 2018.
He is described as white and of medium build with short brown hair.
He is believed to be wearing a navy blue British Airways jacket, black trousers and black shoes.
Roy has epilepsy which requires daily medication to treat, however it is not known if he has the medication with him. Anyone with information about hisÂ whereabouts is asked to contact police on 0161 856 6936.