Kade's Allergies/Asthma and Immunology

This poor, sweet boy suffers with allergies.  Back when he was younger, Kade was diagnosed with allergies and asthma.  He does fairly well while medicated, but there are times when he is miserable and coughs all night.  Then back a few months ago, he had multiple times when he broke out in hives.  We consulted his doctor, and they suggested a trip to the allergist.

There aren't many allergists out here, so it took us a few months to get in.  Last Monday was Kade's appointment.  Praise God, the doctor did NOT think his hives were anything food related.  However, in order to do allergy testing, Kade had to be completely unmedicated for a week before his appointment.  He was miserable.  Runny nose, cough, itchy eyes and nose.  She suggested testing him for other allergies.  

Kade is allergic to dust mites, mold, basically all trees and all weeds.  He actually handled the testing fairly well.  We played cows and tractors while we waited.  Cows and tractors makes everything better.  :)

The doctor said that Kade being so young, his allergies will probably worsen as he gets older, and he will probably develop more.  What makes matters worse, is that he suffers from both indoor and outdoor allergens, and basically year round.  In addition, the allergies make his asthma flair up.  She prescribed Zyrtec, Singulair, Flonase, for daily treatment, and since he was so miserable, we were temporarily on breathing treatments and oral steroids.  She then mentioned Immunology.  Basically, for 7 months, Kade would go in once a week, and receive 2 shots that were specially mixed for him, with small doses of his allergens.  After 7 months, he would go in every other week, and gradually taper off.  The allergy shots are a 5 year treatment program.  Ugh.  However, she said it would decrease his symptoms and keep him from getting any new allergies.  Her hope would be that he would be able to not require all the medications. 

Marc and I have talked a great deal about it. I think in the long run, the shots would be beneficial and make the most sense, but I'm having a hard time with how young Kade is.  I've spoken with some other medical professionals and mothers.  They all say the same thing.  There isn't a medical reason to not start them now, but being under 3 years of age seems awfully young to have to sit through weekly shots.  Once we start, it is a huge commitment. I think we will do it, but just not sure at what point.  

Has anyone out there had any experience with allergy shots with little kids?  Any and all advice would be greatly appreciated!