Grain and/or gluten intolerance and Seder night

[RabbiM]

Many people are gluten intolerant and have a hard time eating Matzo
even on Seder night. For some of them, it is a gluten intolerance and
by avoiding wheat matzo and substituting spelt or oat matzo the
problem can be resolved. (Incidentally, I am told that machine oat
matzos are low in gluten but not gluten free, while the hand oat
matzos are gluten free. I have not been able to confirm this yet.)
But others are not able to tolerate spelt or oats. The sheilah I was
asked today and would like to discuss is as follows: A lactating woman
who has severe stomach cramps when eating grains, and also causes her
baby to become somewhat sick and uncomfortable when nursing
afterwards, asks how much matzo is the absolute minimum she should
have.
Probable answer is to eat a full kezayis for the first matzo, then a
nominal amount for korech, and a small estimate of a kezayis for the
afikoman. The reasoning is that a person should not skip the mitzva
de'orayso of matzo if it only causes discomfort, but for the korech
which is only a zecher if someone cannot tolerate a shiur she may eat
any amount however miniscule. The afikomen is considered by some
opinions to be more important and therefore one should eat the
smallest estimate of a kezayis if possible. Someone who cannot take
more than a very small amount should eat only the first kezayis.
Rabbi Avrohom Marmorstein