As already mentioned this is a Thailand wide problem but probably bigger in Issan. I too have experienced the impact on extended family due to this drug and also alcohol in general, you could also throw gambling into the mix. To a degree at least in “my area” l believe poor education, lack of employment opportunities, peer group pressure and a limited understanding of personal accountability all contribute to the problem. However in fairness illegal drugs are a world wide problem, the main difference l see from Western Countries versus Thailand is the possible lack of support services. My wife and l refuse to financially help any family members who take drugs, drink or gamble, we are lucky such issues only impact extended family members.