I've seen vitamin supplements marketed as "stress formula" - usually w/higher doses of b vitamins. are these safe to use and do they work for stress?

Don't waste money!: There is so much false hype in marketing vitamins. No vitamins will have any effect on stress. If you eat a normal diet and not pregnant, you probably don't need vitamin supplements. But if you feel you might benefit, choose the cheapest multivitamin on the shelf and ignore claims like stress reduction, improved energy, immune system boosting, etc.