Friend's baby, not mine, so apologies if I can't give alll the relevant info. He has never slept through the night and is now waking at 4ish crying (goes to bed around 7, has a feed around 10 I think). He isn't hungry and seems tired and as if he wants to go back to sleep. He continues to cry for about an hour (regardless of whether picked up and cuddled or not) then drops off again. Paed thinks might be lactose related and advised weaning (he's nearly 6 months) and switching to non cows' milk formula, and she has just stopped breastfeeding him, but so far still waking and crying. He's also taking gaviscon. He's fine during the day (bit sicky maybe but nothing really unusual).
Solutions that are based around sleep issues don't seem to work (e.g. cc, baby whisperer type approach) because there appears to be some physical discomfort.
Anyone have any ideas about what it might be, and how to help him?