I usually get re-tested every 2-4 years. Just whenever it doesn't seem like my shots are controlling my symptoms the way they should. Supposedly some people will reach a point where they can be on shots for about 2 years and then have 2 years where they don't need shots, but it's never worked that way for me. I think there was ONE allergen I didn't react to on my last test that I had reacted to before.
But my level of sensitivity to different things definitely varies over the years, and that's why I get re-tested.
You can go back on your antihistamines as soon as they've checked your wheals for a delayed reaction.
+1 on changing my life!
Speed comes from what you put behind you. - Judi Ketteler