Two and a Half Men Season 4 Episode 16

Charlie is getting older, making love every day or more exhausts him physically, to the point of needing a rest between bangs. So he needs to take his girl Robin -24, about half his age- out again, and brings Alan dancing to a club for her 24-year, ugly girlfriend, a recipe for a miserable night followed by a brotherly row. Then Charlie gets chest-pains, Alan brings him to hospital, clearly worried even more when he hears the beach-house inheritance comes with a mortgage. After Dr. Prajneep finds it's only gas, Alan takes Charlie to a 'fountain of youth' for their age...