Garlic!

Will there be anything she can eat in most places?

Almost everything but Bagna Caöda; (un)fortunately it takes ages to cook the Piedmont's "national" dish, so you wouldn't find it on menus anyway. If you see Bagna Caöda on the menu posted outside, that's a restaurant with a real chef where you should eat.

Garlic is not very used in Italian cuisine and when it's used to flavor olive oil in the pan, it is rarely left in the dishes to the table. If you decide to "eat Neapolitan" one night, Avoid any pasta dish based on shellfish. Clams and mussels are simmered with garlic.

If, for mysterious reasons and unspeakable perversions, you decide to "eat Tuscan"... avoid the Pici all'aglione pasta and all the Bruschetta starters. Out of Tuscany Garlic bread is unheard of, but the Tuscans eat its ancestor called Bruschetta (and the all family is quite disgusting imho).

Thanks so much; that's very helpful!

Print on a 3 by 5 card, in large print, in Italian that your allergic to Garlic, show it to the waiter. J

My husband is from Turin and he is also allergic to garlic.

Most stuff doesn't have garlic unless it's specified (such as bagna cauda as Dario mentioned above, or pasta peperoncino et aglio...)

Just make a little card that says non posso mangiare dell'aglio and be sure to share it with your server or whoever you are buying your food from. But it's not in most stuff. Dario has given you spot-on advice.

Good thought with the preprinted card; thanks!

As a long-time food allergy traveler, I have a few other thoughts:

Does your wife use an Epi-pen? Then bring two in case you use one.

Carry enough Benadryl that you don’t need to buy more while you’re there - I can’t readily find Benadryl in Italy.

I gain a little “wiggle room” for my allergies when I take a daily Zyrtec when I travel. I did this for many years - but haven’t recently.

The food card is a great idea but I’ve had a few failures with these - where I hand over the card, think we’re all set and still get an allergen delivered to me.

In addition, if your wife has an anaphylactic garlic allergy - put that on the card.

I have a few food allergies. Only one of them really freaks me out - the others cause some eye swelling and maybe some hives. But for the big one, if I felt I was in a country where I couldn’t sort things out on my own, I would have my card say something along the lines of “If I eat this food, my airway will close and I will need to go to the emergency room”.

I think that there’s a lot of food intolerances out there, along with milder allergies, and then the life-threatening allergies. So I think restaurant responses vary. If your wife has a perilous garlic allergy, make your card specific as to that.

Just tell the waiter your wife is actually a vampire and she is absolutely ALLERGICA ALL'AGLIO (aglio is pronounced 'allio' with the sound of the Spanish double LL, or like the English 'million').

Valerie - thanks very much! Hers is more of a vacation-ruining "up at midnight and complete loss of cookies" thing than being life-threatening.

Roberto - on top of that, she's a night owl. I've been suspicious for years.

If the allergy is serious could be a problem. In several tomato sauces the garlic is used at the beginning of the cooking ("arrabbiata" sauce, as example). In Piedmont, being the traditional food hugely affected by France, there are several dishes who use butter and garlic as sauce, like for example snails.
"Aglio di Caraglio" is even a protected food of Piedmont, so in some good restaurants probably they are fond to use it.