On the high mountains of the Qinghai-Tibet region, many people suffer from difficulties in breathing. Tibetans can improve this situation by ingesting powder burned from black datura, or by carrying an aroma pouch of the same. When used in the Central Plains, it can refresh the mind, but occasionally it can cause headaches or even block the meridians.
Besides, it is also used by Tibetans to nurture a supernatural being named "Dahei Tianling", who specifically attacks human brains. I'm not sure whether it has anything to do with the Crown Prince's sudden illness.
Also, the consecration of the Jinping Dharma King was completed last October, but they didn't start their journey home until shortly before the New Year. It should be known that Tibetans also celebrate the Tibetan New Year which is about the same time as ours in Central Plains.
