What can I give her being that she is really weak? She has been to the hospital 3 times for colitis and she was doing well until 3 days ago.

Ulcerative colitis is awful and eventually becomes Chron’s disease. My oldest daughter has it. There are meds but this situation takes so much out of a person. Sometimes surgeries are needed. My daughter has had surgery. Lots of time in the doctor’s office and hospital. No fun. A lot of stress. Special diet needs to be followed. It’s a mess. My heart goes out to you and your family.

So sorry that she is suffering with this dreadful disease. Hugs!

More information would help.   I've seen someone devastated by colitis, and only a DX from a competent physician helped her recover, but she was in her 40's.

How old is this person?   I assume you're her caregiver?   For how long?  Is this a first time DX? 

What preceded the hospitalization and over what period?    If she was debilitated and dehydrated for several days, her recovery will be longer.  

Does she have any co-morbidities?

If she is in the hospital I personally would give her nothing unless OKd by the doctor who is taking care of her. She should be on an IV for liquids. I would ask what they are doing for her weakness. Are they supplementing her with ensure or something like that.