Have been told to reintroduce dairy every 6 weeks?
Every 6 WEEKS?!?!?

I'm with Deb on that one!
Just to clarify something on this - if your doctor is suspecting a lactose intolerance, then 6 weeks is normal for a challenge, many even say every 2-3 weeks. True lactose intolerance in babies and children is VERY rare, most instances of it are temporary from a bout of a tummy bug while the digestive system gets back up to speed and functions at 100% again, and so most doctors will say to challenge every 2-3 weeks, and normally that is about all that it takes.
Milk intolerance/allergy is different to lactose intolerance, and yes, challenging every 6 weeks for a milk protein issue is not a good idea. (milk intolerance or allergy is a reaction to the protein in the milk, lactose is the sugar in the milk). If your doctor initially prescribed lactose free milk then it does seem like s/he was going down that road, and so a 6 week challenge makes sense and is not bad advice. I would have a very open discussion with your doctor and specifically ask if he thinks this is milk protein intolerance or lactose intolerance.
Well, went to pharmacy to returned the unopened and unused milk as they gave me a ridiculously large amount and they just destroyed it! Shocked
This is for safety reasons! There is no way to be 100% sure that you have not lifted the seal on that container and sealed it back up, or that you have not in any other way tried to contaminate the milk powder! I know it is frustrating and such a waste, especially when YOU know you are an honest person and haven't done anything! I was fortunate to inherit a box load of eczema creams for DS when the local chemist filled a friend's prescription wrong, when she found out they were going to destroy it, she shipped it to me here in Germany where I would have paid big bucks for it!!
oh that makes me so mad about Dr's!!! i was also told that ANY reaction of any kind we need to leave another trial for 6 months to allow the stomach to settle back down and not react so drastically again, why risk it, its only 6 more months they have to go without it.
leaving it 6 months sounds like perfectly reasonable, healthy, good advice to me! some doctors are more conservative than that, our paed was strict that a failed milk trial at 12 months meant dairy free until 24 months. elimination diets and food challenges are pretty much the only way to manage a food intolerance or allergy, and allowing a child's sensitive digestive system to settle down and heal from damage is crucial!