Droopy eyelids is known in medical terms as eyelid ptosis. There are many potential causes of droopy eyelids, going from medication related (opiates), autoimmune disorders, tumors, paralysis of the muscle that lifts up the eyelids (elevator aponeurosis), mechanical, or related to aging. Some children are born with ptosis and this is known as congenital ptosis. 

The first step in the management of droopy eyelids is to determine if this is an acquired condition or if the patient was born with it. Most cases of ptosis are acquired. 

As a plastic surgeon, the majority of the cases I see are related to aging and laxity of the connective tissues (aponeurosis) that connects the levator muscle to the tarsal plate of the upper eyelid. This is known as senile ptosis. There is a surgical procedure known as tarsolevator advancement that re-attaches the levator muscle and the tarsal plate in a better position to then allow for contraction of the muscle to elevated the eyelid.

It is important when performing a blepharoplasty (or removing skin from the upper eyelid) that we identify any patient that has underlying ptosis as these patients will continue to be unhappy and will continue to complain of looking tired post-op if the droopy eyelid is not corrected. 

This is the importance of finding a board certified plastic surgeon with additional training in advanced oculoplastic techniques.