How many days of constipation before calling a doctor?

Depends.. Some people can go for a few days - 3, 4, even 5 without having a bowel movement and be okay - it's just their "normal". We look at other things: is there a lot of abdominal pain, vomiting, fevers? These are more concerning things in association with constipation, and i'd see a doctor if this is happening. Otherwise, lots of liquids, prunes, fruits and vegetables... It'll eventually happen!