How quickly can the body become addicted (physical, not psychological) to low-dose opiates?

Assuming the patient is taking normal prescribed/directed doses for legitimate purposes and not using it to get high. Let's say, standard over-the-counter T1s (Tylenol with 8mg of codeine, a fairly low dose), one to two tablets every four hours. So long as the patient isn't abusing his or her medication and doesn't use it as a long-term treatment, is there any significant risk of developing a physical dependency? I know it differs from person to person, but I'm just looking for a general idea here.

: http://alcoholdrugstreatment.info/how-quickly-can-the-body-become-addicted-physical-not-psychological-to-low-dose-opiates