Answer:
There are a lot of risks that are associated with her, She may harm herself, as she is not in her senses. She can also harm others as well. She can get unconscious and fall away and can get injured. She can also get some car accident etc. She can also be easily harassed by other people.
To legally enjoy the celebration safely, she should abstain from any kind of drink and drugs that can cause harm to herself and others. And she can also hire some driver or anyone who could safely drop her at her place after party.