Ok.
But lets see.
She doesn't want him to do it?
Here is a list of why;

-Kills brians cells (for the love of god dont tell me it doesnt)
-It makes you lose memory
-Loss of deep thinking for a while
-If they plan on having kids, he could mess that up.
-It's S T U P I D.

There is no reason for drugs.
If your reason is to get away from the real world.
Read a book.