Yea, lacking of sleep can cause the ptosis. We all know that the ptosis come into being when our eyelid drops down. When we do not sleep enough, namely, our eyes do not have a good rest, and the eyelids will drop down when we get up next day, then you will have a date with the ptosis. Of course, if the ptosis is not heavy, it will come back to normal after a few hours. If the ptosis is heavy and obvious, what you should do is having a good rest letting both you and your eyes have enough sleep, then the ptosis will go away within several days. Yeah, when you found you get the ptosis, which cannot tell you do not sleep well, because there are some other reason why you get the ptosis, such as the anxiety. Hope my opinions help you and good luck.LOL.