Per medication admin protocol, subcutaneous injection should deliver
medication into fat tissue -- locations suggested on body map are
specified because those locations usually have adequate subcutaneous
fat layer. Evidence of resulting tissue inflammation may further
restrict suitability of injection sites. In practice, even when
receiving several injections per day (as in the case of insulin and
heparin administration for diabetic patient on prolonged bed rest),
patients usually prefer injection sites rotated around quadrants of
abdominal area. Obvious exceptions occur in cases of trauma or when
patient is simply more comfortable with other sites.

In my own experience, moving from one quadrant to the other for my
weekly IFN injection worked out well, especially as site locations
within each quadrant were also varied. Interestingly, some inflammation
was evident at each injection site for up to three or four weeks post
injection. Although the spots were usually not particularly noticeable,
whenever I'd just stepped out of a hot shower the trauma was readily
visible in the mirror as silver-dollar-sized bruises. Repeated
injection at such sites of inflammation I suspect leads to the problem
that greyhackles reported here:
http://groups.google.com/group/alt.support.hepatitis-c/browse_thread/thread/e7cc
5665e09a681/a713a06f89f71fe6#a713a06f89f71fe6.

bg