Oh goodness, do I ever know about dogs with allergies!

I would try to avoid the steroids. It generally is only going to make her immune system weaker and therefore, can actually BRING ON more reactions and allow bacteria to cause skin infections for which you'll need several weeks of antibiotics. You say she was on monthly injections and they suddenly stopped working? Oh yes, been through that several times with Chester. Actually going through it right now. He's been tested multiple times and each time he has NEW things that he's allergic to and they have to adjust his 'shots'. He's going in this month for testing yet again since the last month has been horrible. Hopefully they'll find something new and we'll just change his antigens again.

As far as antihistamines, OTC you can always give Benadryl, chlorpheniramine maleate (brand name Chlortrimeton) and for prescription there's clemastine (brand name is Tavist, but you CANNOT give Tavist D which has a decongestant, thus the 'D'), and hydroxyzine (I THINK the brand name on this one is Atarax or something close to that). You would need to get with your vet for dosage before giving any of these because it's dependent upon their size.

You say she's on a hypoallergenic food, but which one? Chester can't eat any of the traditionally hypoallergenic foods. He's allergic to lamb, chicken, turkey, beef, etc. No allergies to the usual suspect, corn and wheat, though. He's been on Solid Gold Holistique Blendz for several years with good results, before that we were on Wellness and did good allergy wise, but had loose stools.

Anyway, I wish you luck and feel free to PM me if I can help in any way!