Suggest Treatment For White Hair Growth In Child

I have a 13 year old daughter who has a white hair which started at the age of 8 year, when we consulted Dermatologist he prescribed some calcium tablets i.e. Sigma panthonet and pabatab. While taking that Hairs had turned to be slightly blackish later it started growing more white. We stopped the medication Please advise is their any medication is their as she is quite young and scholl going child. If I can get your kind advise on my email YYYY@YYYY we will await for your kind advise and meet. regards. CHAVAN