What allergy medicine can my wife take while we're trying to conceive?

Any: Can't think of what she could take that will interfere with fertility.

Depends on symptoms: Depends on what problem your wife uses allergy medicine for. I'd try to avoid any medicine in the first 12 weeks if possible. Neti pot for nasal rinses works a like a champ in patients with allergic rhinitis. Rhinocort is listed category b. It is a nasal spray and works great in people with the above problem. Claritin/zyrtec and Benadryl (diphenhydramine) are otherwise safe to take as well.