My son is 5 months old. Born at 37 weeks with intra uterine growth restriction at 5 lbs 10 oz and 18.5 inches. Today at 5 months he weighs 15lbs 2 oz and 25 inches which is still low on the charts. He has MSPI and severe GERD. We just tried sweet potatoes for his first food last night and low and behold 2 hours later he projectile vomited 3 times. I was able to get 2 oz of formula in him before he fell asleep. Being a nurse in Peds I kinda knew it was a possible FPIES! Now I'm absolutely terrified to try another food. We cannot get an appointment with the FPIES specialist until May of 2017. I guess luckily he's only 5 months so he doesn't really need solids. I just don't want a severe dehydrating emergency situation... how does everyone else do this?
Just do what you know what works for right now. Like you said, he's still young. I wouldn't try a solid again until after the appt. If possible. But if you do, only try ONE thing. And if it works only give that solid for a while until you have a game plan with your doctor.
The beauty of five months is that you don't need to give him any food - breast milk only . I wouldn't worry about introducing anything until after you see the doctor .
Its a hard road, mine diagnosed with FPIES at 7 months, he was intolerant to most foods only tolerating fruit at the beginning. I started with formula, rice cereal, wheat cereal and he reacted to those in different manners none good. Sweet potato, tomato, capsicum and egg plant are all part of the same family so intolerant to one, most likely intolerant to all. His first foods tolerated were pears, apple, carrot. My baby is now 3 1/2 he has finally grown out of all food allergies and intolerance's. But it doesn't stop here, he is scared of food and it will take a while to build up his confidence to try new foods. I wish you and bubs all the best.
My best advice is to keep yourself sane first and write a log for what happens with the little one (food/illness) to be able to best correlate all the things that will happen. This stuff is stressful and without your witts, you won't have the ability to apply yourself best. Frankly, I've yet to hear of any over-the-moon experiences with doctors helping us with this stuff.
I had the same fear with our second who had FPIES. Even though our first only had FPIES to one food and her growth was fine. Our allergist actually told me that solids before one weren't necessary (he was saying it in reference to breastfeeding but my guess would be with formula that's similar). Also, he cautioned me that FPIES appears to be related to gut development. So the longer you wait to introduce foods the less likely a reaction is to occur. The opposite advice of traditional food allergies. Wait until you aren't terrified anymore or are ready to try foods and then look up the FPIES survey. It's online somewhere. Then, if you can, start with the safest foods on that list maybe. Avoid the common triggers (sweet potatoes, wheat, rice, oat, soy, dairy (MSPI means you probably do already), avocado, banana, peas, etc.)