well i have a basset hound and an english mastiff... the basset being carsick also we have had no luck either so we just tend to have somone rub his belly and have a bag hands incase that doesnt work i have found that that works for me i have also found that when he has hiccups then it also works but u can try it for yourself and if not then sorry i couldnt help. keep in mind that what u had stated that your friends dog has it worse then mine.