My kid is 5, and if he is in a car for more than 5 mins, he pukes. Every. Single. Time.

He has some unrelated health / learning issues which means lots of appointments / travelling. I don't drive, and I can't put him in a taxi due to him vomiting and just this morning I have had to ring and cancel a hospital appointment because the first bus of the journey didn't turn up. He is fine on buses and trains, but we live semi-rural and the public transport is sparse and unreliable.

So far I have tried: Kwells tablets (hyoscine hydrobromide); Avomine tablets (promethazine teoclate); travel sickness bands, travel sickness herbal patches (stick one behind the ear and one below your naval). Even using these altogether it works for 10 mins max, and he pukes again. GP said he is too young for any prescription stuff.

People of the UK, (apart from leaving earlier for public transport which honestly sometimes isn't feasible) do you have any other ideas to solve this? Thanks!