He's absolutely right that the allergy testing is NO BIG DEAL at all. My daughter was 22 months old when she had a full screening of allergy testing done. It's not like it used to be. It's more like taking a spoon and scraping it on your back. It doesn't even hurt a tiny bit. My daughter had a blast while she was there because she got to play with a ton of their toys while we waited for her test results. She wasn't itchy at all or anything on the things she was highly allergic to, they just got red and patchy. As far as the other symptoms, my son has eczema and has had asthma problems in the past, especially up until age 4 (he's 5 now) The eczema turned out to be mostly keratosis pilaris, with eczema flareups from time to time, and the asthma symptoms became less and less frequent to the point that over this past winter we didn't have to give him any treatments at all. Some kids are just sick a lot when they're really young. Both of my kids were sick almost nonstop from January to May, and this year it seems like we've only had a couple very small colds run through them. I've never had my son's pediatrician recommend allergy testing, and with my daughter, the reason for her testing was because she had a chronic sinus infection and they were ruling things out before they opted for surgery. She ended up getting her adenoids out and tubes put in her ears, which again was not a big deal at all. She was up playing like normal by 6 that evening.
It's scary when your little ones are having problems, but great that other moms can share their experiences with you to put your mind at ease. I wish I could remember how long it took for the allergy tests, but it's been 4 years now. I will say this though, it was a longer appt, but not something that when I look back on it I think "man, that took forever". I bet it was less than an hour altogether. Oh, and also, I wouldn't even say anything to her. You will just make her anxious. Just let the doctors explain to her. With my daughter, they said, I'm going to tickle your back with all these different things. She didn't care, she didn't even flinch when they did it unless they really tickled. She sat and played the entire time. It would be a good idea to maybe let her buy a new toy so she is distracted while they're doing it, that way she isn't moving around a bunch. It won't hurt her or anything, but if they're doing a lot of testing, they're going to want to be careful to keep everything separated into their own areas.
By the way, I didn't have to hold my daughter down AT ALL. I noticed one of the other women said you'd have to do that. With my daughter, she just stood there playing while they did all their scratch tests on her back. I can see them having to hold down a child who was fighting the testing, but if you don't make a big deal out of it, and you keep her busy either with a book or a toy, there's no reason why a child would refuse to have it done and have to be held down.