I'm not sure about the weight issue, is she on enzymes? Is she breast fed and are you fortifying or is she on formula. How is her reflux? Ellie was breastfed and I was fortifying up until a month ago, pumping wasn't working so we had to switch over to formula. We use enfamil with iron but make it 24 calories. I also had rice cereal because her reflux was pretty bad so we use it to thicken (she likes the banana flavor, rice cereal also adds extra calories). We use about 3 tablespoons to a 4.5 bottle, it is pretty thick, so we had to make the hole in the nipple bigger. Our doctor also recommended adding 1ml of mct oil this is a prescription but before we got the prescription we used corn oil (mazola) to each bottle (shake it well, so she doesn't notice, this is a little extra fat. When we have done this (and she doesn't burn extra calories because she is breathing so fast) she gains approximately 4-8oz in a week. Ellie also likes her bottle pretty warm, she can be soooo picky. Have you tried her on any solids. My peditrician also says it's okay to give her half strength apple juice (yay...extra calories) I'm also trying to figure out what a scandishake is, but she still might be a little young for that.
Ellie is doing the same exact thing with her fist, she even gags herself sometimes and makes herself throw up. Every toy she grabs also goes straight to her mouth. She's also drooling a bit, we think she might be teething too. She will have nothing to do with a teething ring though. She really likes cold paper towels or oral swabs (not the flavored kind), she also will suck in a frozen carrot (the big ones, not the baby ones). I haven't tried baby orajel yet but I am thinking about it. We haven't seen any teeth yet, but it seems to make her feel better. I hope this helps. When is your next doctors visit? Hopefully you'll have a couple of weeks to try to put weight on her. Is it the type of feeding tube that goes down her nose? Ellie had one of those on one of her hospital stays for a couple of days. It did bother her, but I know it was because she wasn't used to it.