Hey Ana, I finally caught up with this thread...
Maya was allergic to dairy but no one told me to give up dairy when I was bf so she got sicker and sicker and eventually ended up in hospital where I was *encouraged* (read INSTRUCTED!) to give up BF and put her on prescription formula.
If I had only known that giving up dairy myself would have helped the problem I would never have stopped feeding (BTW she was 10 mths at this stage, her weight loss/funny poos etc. started around 16 weeks).
A dairy free diet is not that tough. Lite Licks icecream is dairy free, the only biscuits that are are Gingernuts as Maria has said. They do say on the label that they contain milk, but this is only a recent change due to stricter labelling laws, our dietician has assured us they are fine.
Most breads are dairy free apart from some of the really heavy Vogels, Burgen or grain breads, Olivani spread is dairy free (the only margarine that is), soy yoghurt, soy milk (rice milk tastes nicer tho), avoid soy cheese tho as it contains casein which is dairy protein.
Rice crackers (only the plain ones tho as some of the flavours contain milk in the flavouring), Chicken Crimpy Shapes crackers (the only Shapes that are dairy free, in an orange box).
Hope this gives you some ideas to start with. Avoiding peanuts is probably a good idea too as a high percentage of kids with dairy/gluten/egg allergy are also allergic to peanut.
Just a thought too, has he been tested for Coeliac (gluten intolerance). That can be a cause of bloody bowel motions, Maya was tested for it but thankfully negative.
PM me if you need any more ideas, this has been my life for 2 years so I am getting pretty good at it