It is often very difficult to stay calm when you are young and you prove to be one of those unlucky teens that, with any acceptable explanation, lose their hair. Somehow, society forgives the young who lose their hair because of chemotherapy for cancer or as a result of some other natural accident. But any other hair loss marks you out as uncool.
Some catch one of the fungal infections such as ringworm that leaves large swatches of hair on the floor as they walk around if they are really unlucky. This is deeply humiliating. Then you have the style conscious who put their hair under pressure by pulling it into position. After a while, pulling at the hair makes it fall out. But then come those who can be accused of having weak genes. Medical research confirms that male pattern baldness can affect teens as young as fourteen.
When the FDA were reviewing the evidence from the medical trials, it was aware that male pattern baldness was possible among the younger teens, but it decided to limit the prescription license to those aged 18 and over. The decision by the FDA is always a balancing of benefits against risk. Young bodies are still going through the maturing process and the levels of different hormones can be changing quite quickly. To intervene in the balance of hormones in the young is dangerous. The FDA therefore erred on the side of caution. In part, this reflects the nature of the drug. It’s not a cure for the genetic problem. It simply controls the process that would otherwise lead to hair loss. Perhaps if it was a specific cure, the FDA might have reached a different conclusion but, for now, doctors are not supposed to Propecia to those under eighteen.
So if this affects you, the choice is either to wait until you reach the magic age and put up with the inevitable problems of bullying, or to beat the prescription program by buying online. Since there can be longer term sexual problems, you have to want to stop the hair loss more than allow your sexual equipment to develop naturally. This should be a very difficult decision to take given the risk of impotence.