Low dose codeine and constipation

[redglow]

SWIM has found that just by taking less than 30 mg of codeine she gets a very disgusting constipation the day(s) after. Is this a rare reaction to codeine with such a low dose or is it normal?

On the other hand, if this is normal, those people that take 200-300 mg of codeine what kind of constipation do they experience? Incredibly exxtreme constipation? Or is the level of constipation still the same whatever the dose?

By the way, does the constipation come directly from codeine or is it the result of its morphine metabolite? If you took an equipotent dosage of morphine, would you get a similar constipation?