Technically, you can use mascara to help stick false lashes on in a desperate pinch, but it is not recommended and will not work like actual glue.
Here is why it is generally a bad idea and what you should do instead.
Why Mascara is a Bad "Glue"
Weak Hold: Mascara is designed to coat lashes, not bond them. Your false lashes will likely lift at the corners or fall off completely within an hour or two.
It Ruins the False Lashes: Mascara is messy.
Coating the band of your expensive false lashes in mascara will make them clumpy and impossible to clean, meaning you probably won't be able to reuse them. Eye Irritation: To get the lashes to stick, you have to apply the mascara while it's wet and press the strip deeply into your lash line. This often pushes product into your eye or clogs your follicles, which can lead to styes or infections.
If You Are in an Emergency (The "Hack")
If you have absolutely no other option and must wear them right now:
Apply a thick coat of mascara to your natural lashes.
While the mascara is still tacky/wet, press the false lash strip down onto your natural lashes (not your eyelid skin).
Pinch your natural lashes and the false lashes together.
Warning: Do not expect this to last all day. Avoid wind and touching your eyes.
Better Alternatives
If you are out of glue, these are safer and more effective options:
Magnetic Lashes: If you can run to a drugstore, these require no glue at all.
Adhesive Eyeliner: Many brands now sell felt-tip eyeliners that act as glue. They are much easier to apply than traditional glue.
Self-Adhesive Lashes: These come with a sticky band pre-applied.
The Bottom Line: Don't risk ruining your makeup or losing a lash in public. It is usually better to just wear a few heavy coats of mascara on your natural lashes than to try to "glue" falsies on with it.
