Will 4 yr old dry martini which has been opend be ok to drink?
Assuming you mean Martini & Rossi Dry Vermouth, then I would say no. The exposure to oxygen over 4 years will seriously degrade the product. Vermouth is a fortified wine with a relatively low alcohol content, not nearly enough to preserve an opened bottle. It won’t hurt you, but it will probably taste like wet cardboard and vinegar.
