Good books about a patient in a mental institute?

Ken Kesey, "One Flew Over the Cuckoo's Nest"

Susanna Kaysen, "Girl, Interrupted"

Andrew Davidson, "The Gargoyle"

Augustine Burroughs, "Running with Scissors"

Wally Lamb, "She's Come Undone"

Mark Vonnegut, "The Eden Express"

Get Well Soon by Julie Halpern

Suicide Notes by Michael Thomas Ford

One Flew Over the Cuckoo's Nest by Ken Kesey (as other's have suggested)

Hope this helps.

Ken Kesey was an American author, best known for his novel One Flew Over the Cuckoo's Nest (1962)

ps. The movie is pretty good also (5 Oscars!), with Jack Nicholson.

one flew over the cukoos nest