Does taking biotin vitamin for hair and nails break you out?

Possible: Taking any medications, supplements or vitamins can cause allergic reaction if you are allergic to them. Also, biotin is often marketed as a product containing other b vitamins such as niacin. Niacin frequently causes facial flushing and feeling of irritation.

No: However, if you have a rash for more than 2 week or you're systemically sick or the rash is obviously dangerous-looking, get seen. And be sure you know what you're really taking -- somebody who'd recommend "biotin for hair and nails" may actually be selling you goodness-knows-what.