Hi, Thank you, Angela! :) I think "allergic to" is the one I was looking for. The phrase is 生理的に受けつけない. The word has a sound of science but , yes, actually it's very harsh criticism saying it's not reason but just can't accept someone/something.

Interesting, what is the Japanese expression? I'm not sure if there's one quite the same in English...but similar phrases are unpalatable eg: "I find them really unpalatable." (referring to a 3rd party) can't take /dificult to take eg "I can't take them anymore" (again referring to 3rd party also used for time spent with someone) can't stomach/ difficult to stomach eg "I just can't stomach him/her" they are about ability to eat or digest rather than to do with allergy. jokingly you can say that you are "allergic" to a person that you dislike...its quite a harsh joke used behind their back. and I should say unpalatable usually comes across as posh and or archaic.

Oh! The expression is about a person. About disliking someone.

I think you are talking about the word insane. Insane basically means that a person is severely mentally ill. Their issues and personality don't meet social norms. An allergic reaction is very different. An allergic reaction in English describes a health reaction that one cannot control because of certain things. It's like someone being allergic to peanuts. This means that if they are around or eat peanuts, they have a serious medical reaction. Hope this helps!

My body can't handle X. Whatever X is. I think that's what you want to know? Like I can't have spaghetti because I am allergic to wheat. My body can't handle wheat.