Hello,

I don't really know what medicine is best for guests, since I wouldn't
want to give someone anything, then find out they were allergic to some
ingredient in the drug, and be worse off than when I started.  My
guests who know they have allergies to cats usually take something
before coming over.  If your mom just discovered she is allergic, she
may want to discuss with her doctor.

But, you can try to reduce the amount of allergens in your home to
minimize the effects.  There are shampoos that supposedly remove the
dander from the cat.  I haven't tried these yet, so I can't tell you
how well that works.  What I do do in my home, though, is use pet
release carpet stuff when I vacuum (a powder by Arm & Hammer).  Vacuum
often, and then spray Allergen reducer Febreze on anything fabric (test
per label instructions, of course).  This seems to help, but I don't
think it would remove the problem altogether.