HOLLYWOOD legend Nick Nolte's always been an oddball, but lately he's been extra forgetful and seemingly out of sorts, leaving worried pals pushing him to get a check for brain-savaging Alzheimer's, insiders say.

Sadly, the 81-year-old Down and Out in Beverly Hills star is no stranger to the Alzheimer's nightmare his beloved grandmother and a father-in-law were victims.

"His loved are worried, and he's worried too because his memory is waning and isn't as sharp as it used to be and he gets frustrated when he can't remember things,” spills an insider.

"His grandmother had Alzheimer's and it broke his heart to see her get confused and not be able to recognize him.” Insiders say those close to the Angel Has Fallen star fear he may even have early stages of the disease due to his bizarre behavior. Says the source, “He walks around in a daze and misplaces things and can't remember names.