TweetGH is predominently prescribed for growth disorders in kids as well as for AIDS patients that are wasting away due to the disease. It's also prescribed, to a lesser degree, for anti-aging benefits.
BTW, Nutropin is equal to Saizen (Serono too), Norditropin, Genotropin, etc... There's no difference between any of them except for Saizen/Serono's presentation. They have the patent on freeze drying their GH, as I understand it, which is why it can be kept on a shelf in a cool, dark place prior to reconstitution. The others need to be in the fridge at all times.