French phrase
Elle est allergique à ~.
Meaning
She is allergic to ___.
When to use it
She is sensitive to a specific substance. This neutral expression is common when discussing whether food is safe for her.
Example dialogue
On peut lui donner ces biscuits ?
Can we give her these biscuits?
Non, Elle est allergique à l'arachide.
No, she is allergic to peanuts.