Fists of Absinthe.

On his maiden trip to Japan, a Samurai-obsessed American named Frank is taken to a local, hole-in-the-wall bar by his friend, Hiro. After being rejected by the first local girl he speaks to, Frank feels down on his luck, and to console him, the bartender offers him a drink called Absinthe in a bright green glowing bottle. To help console his friend, Hiro drinks the bottle with Frank, and the two of them promptly pass out. Together they wake up in Edo-era Japan, and are taken through a comedic time slip action frenzy where they have to work together to battle both samurai and ninja to find their way back home.