30 Second Answer
You should wait at least 48 hours before using a sauna if you have lash extensions.
If you have lash extensions, you should wait at least 48 hours before using a sauna. This is because the heat can cause the adhesive bond to weaken, which can lead to your lashes falling out. Additionally, intense sweating can cause your lash extensions to become loose and fall out prematurely. If you must use a sauna, we recommend that you wait at least 48 hours after having your lash extensions applied.
