Can sedation medication for a colonoscopy cause a migraine? if so is there any way to prevent it from happening?

Probably Not: The factors most associated with precipitating migraines in susceptible people are: stress, weather changes, sunlight and peri-menstrual factors. Although the anticipation of a colonoscopy may be stressful, the sedation you received during the procedure would have made you quite comfortable and is not likely to have caused your migraine.

Migraines: Typically patient's receiving sedation for colonoscopy receive either Midazolam (versed), fentanyl (sublimaze), or Propofol (diprivan) or a combination of the above. I am not aware of these medications typically precipitating migraines but the trigger's for migraines are multiple and could easily include not eating prior to your procedure or mild dehydration.