Pesach: Gluten-free matzah
Question
I have celiac. In recent years, gluten-free matzah has now been made available. I'm somewhat confused: leavening is caused by the gluten, so how can I observe the mitzvah of eating matzah on Seder night by eating matzah that can't become leavened?
Answer
The Medical Encyclopedia by Rabbi Prof. Steinberg states that most individuals with celiac do not have an issue with eating a very small amount (a kezayit or two kazeitim) on Seder night as a one-time occurrence. Only a minority of those suffering with celiac are extremely sensitive and cannot tolerate gluten whatsoever (to the extent that it is life-threatening or cases of extreme discomfort). For these individuals, the question arose of whether they can fulfill their mitzvah on oat matzah, since they cannot become leavened. It seems that since this involves a halachic doubt, one should listen (and answer amen) to the blessing on the matzah from the one leading the Seder, and then proceed to eat the oat matzah. In this way, one fulfills the obligation according to all opinions. For a comprehensive discussion of the topic, see Ohala Shel Torah V §43.
See as well Rabbi Yaakov Ariel's answer, here.