My son is 3 now but has been taking Losec since around 11months. I've never been told to take it at a particular time. Dr only said to take it at the same time each day (we chose night as he slept horribly and we hoped to fix it) as its easier to remember. Works a treat for him and sleeps great now too. DS5 takes Zantac twice a day and we were told to just space the doses out so he has one dose morn and one night before a feed as he is usually asleep afterwards. I'd just do what works for you with a bit of trial and error.