, I know this may seem like a silly question, but have you talked to your doctor about your weight loss? Usually, that's a good place to start, but I know many of our members consult their doctors before they post here. Like mentioned, Modafinil sometimes have a "breaking in" or habituation period before your body adjust to it.
The most common alternative I am aware of is Nuvigil (armodafinil) and I know some of our community members use it or have used it in the past.
I do hope your doctor has some helpful suggestions for you as well!
Best, Erin, MultipleSclerosis.net Team Member.