Yes drink water to hydrate yourself, and also keep heat on the arm right on the vein before you have it put in and that generally helps push the babies up. I have the same problem and it is a pain.
Diagnosed: 2003, age 18 (had issues with it since I was 12)
Meds for crohns: Remicade every 6 weeks, 6-mp, Nexium (GERD)
Other medical issues: Hereditary Spherocytosis (hemolytic anemia) iron deficient anemia, polyarthralgia, ovarian cysts, Migraines, GERD
Surgeries: Spleen, Gallbladder, Tonsils, Adenoids, foot of terminal Ileum, Appendix, Ileocecal valve, bit of colon