i'm kind of an amateur herbalist, so this is what i can tell you....it can leave one hell of a rash! Its unlikely a serious reaction will occur, but it has happened, and the first couple of times you use it you should proceed with caution (its the second and third stings that will cause the most serious reactions). Its an edible plant, but if you plan to use it on their tongue (ouch!), which i don't recommend, be sure to use the youngest leaves because the older ones will grow deposits that can cause kidney trouble. Its sting is used therapeutically to numb pain, kind of like capsaicin, so using an extra cream might not be effective once the nerves are overstimulated. Hope this helps