I haven't had a colonoscopy since I was very young and can barely remember it. I'm set to have one Monday and am very nervous, mostly about the prep. I have been unofficially diagnosed with Crohn's. I'm taking the OsmoPrep, which is 32 pills, and I'm only 96 pounds (24 years, 5'6). I really don't want to be sick all night from the pills the night before my procedure. Is it okay to take Phenergan or Zofran? I forgot to ask about these specific medicines and now it's the weekend. Any advice or personal experiences?