Pesach: Matzah for those with celiac
Question
Someone with celiac, who cannot eat regular grains—even oat matzah—can only eat matzah made of gluten-free grain. Can he fulfill the obligation of eating matzah on Seder night with this special matzah?
Answer
My inclination is to rule for those with celiac, who cannot tolerate matzah from the five grains unless the gluten is extracted from them, that they eat gluten-free matzah without a blessing. In this way they will have fulfilled their obligation.
For this purpose, we need to distinguish among the various degrees of celiac. There are those who have a serious gluten intolerance, whose life will be endangered if they eat a kezayit of regular matzah. These individuals will certainly be completely exempt from the mitzvah of eating matzah, since it’s life-threatening. They should eat gluten-free matzah to fulfill their obligation, since this mitzvah is possibly biblical (safek de'oraita). There are those who are not as severely affected by celiac, whose lives are not endangered, but will suffer immensely if they eat it. This leniency also extends to these individuals: they are permitted to eat their first kezayit from gluten-free matzah as well, since they are also exempt from this positive injunction (see Ohala Shel Torah II 92). In contrast, there are those who only have a minor stomach ache after eating a kezayit of regular matzah. In this case, they should eat the kezayit of regular matzah to fulfill the possibly biblical injunction.
See as well Rabbi Yehuda HaLevy Amichay's answer, here.