My 22 Year Old Son Has Been Diagnosed With Severe

My 22 year old son has been diagnosed with severe ulcerative colitis. He is currently taking prednisone and Lialda. We were told to take the Lialda with dinner, but he seems the most uncomfortable in the evening, and taking those 3 large pills is a struggle. Can he take them earlier in the day with food? Last night he vomitted, and I know the medication is crucial for his recovery. I'm just trying to figure out if earlier in the day would be fine, as I know he needs some food to accompany the pills.