My daughter who has CAH also experienced precocious puberty.  She started taking Lupron shots at the age of 5 and stopped them around 13.  These are given once a month and the dose can be increased as needed.  The shots were very effective for her as they stopped the advance of puberty and allowed her many more years of growth.  If your friend has any questions, she can e-mail me and I will try to help her all I can.

Kay