Lewis Ramos, 26, had been receiving treatment after being sectioned under the Mental Health Act on Saturday, 19 March.
He absconded from the facility at around 5.30am on Sunday, 20 March.
Ramos has links to Staffordshire and the West Midlands.
He is approximately 6ft tall, of stock build with bushy black hair and was last seen wearing a green tracksuit with a hood and black trainers.
Members of the public are advised by police not to approach Ramos – if he is seen please call 999 immediately.
If you have any other information about his whereabouts please call 101 or tweet @MetCC and quote 22MIS009365.