just used an alarm with my 8 year old, as in some instances the kids are such heavy sleepers that they will eventually burst/leak, whether they are producing hormone or not. the alarm didn't wake her up (!) but it woke me, so i then went and woke her etc etc - eventually the body trains itself to wake when they hear the alarm (presumably as a more favourable option that me appearing, banging, clapping, putting lights, shaking her awake), and then wake before the alarm goes off... paed told me there are 3 reasons for bedwetting
1 no hormone
2 extremely deep sleep
3 mixture of the above
they usually try medicating first assuming (1), if that doesn't work, an enuresis alarm (2) or both (3)
meds didn't work for dd1, despite doubling the dose, but the alarm was truly fantastic used alone
until they are 8, no-one bothers as it's v normal.