Bad news on the Demulen; they were the last lactose-free holdout.
But to clarify; the original list of symptoms given were not
LI symptoms but dairy allergy symptoms, and unusual ones
at that. I still think it is unlikely to get those symptoms from
lactose added to a medication. I would carefully check a
great many other possible reactions first, to see if any of
them were the cause. If you rule everything else out, then
fine, lactose is the problem. But only then.
Steve Carper