I'll ask about Zantac, thanks! That comes in liquid too I think?
Thanks Ela, if there's 1 box you see, if you wouldn't mind grabbing it - but if not, don't worry. I'll keep trying various contacts to see if anyone can help before the new year and in the meantime, give the old stuff.
The locum vet doesn't think it would be harmful, just may not work as well.