Lactose intolerance in Pesach – possible solutions

Here are Instructions offered by the OU:

"Lactaid production is likely to involve chometz. This renders chewable lactaid tablets problematic.However, our Rabbinical authorities have decided that lactaid milk is permissible if purchased before Passover since any chometz contained within Lactaid milk would be nullified (batel).
Lactaid non-chewable tablets are more complicated. Many rabbinical permit non-chewable vitamins and supplements without regard to their kashruth status. According to such opinions, one may take these tablets just like any other non-chewable pill.
Other rabbinical authorities believe that vitamins and supplements are akin to food even when swallowed. According to this opinion one may take the lactaid tablet when wrapped in tissue paper. However, one who is unable to do so may swallow the tablet without wrapping it, and rely on the lenient authorities, since milk is such an important health need.We suggest that you consult with your local rabbi as to which of these opinions you should follow.We certify a number of lactose reduced products for Passover."

In summary:
Chewable Lactaid tablets should not be used. However, you are allowed to swallow Lactaid capsules in Passover. If no capsules are available – only non-chewable tablets – it is under halachic debate (Machloket) so these should preferably be swallowed in a thin paper wrapping. But as I said – capsules are permissible as taken normally.