Hi S.,
So sorry to read that your wee one has this painful problem!! OUCH! That is the worst and I do hope that you can have success in helping her normalize her digestion soon. I feel bad for you both!! My daughter had some brief bouts with constipation when she was a tiny baby and it was so sad and frustrating to see - I wanted to help her and give her instant relief!!
As you have doubtless read already, stop that Karo syrup!! :) That was very poor advice you were given, not your fault, and on top of that it obviously hasn't corrected the actual problem at all. It's so frustrating when a doctor is not up to date on healthy nutrition and information, especially a pediatrician. We trust them to know what they are talking about in dealing with our precious babies! That being said, I tend to check EVERYTHING out for myself and fortunately our ped is very much in agreement that we are partners in my daughter's healthcare.
Something else to consider for your daughter's wellbeing is that the Karo syrup may also even have contributed to her being so big for a 4 month old too - refined sugar like that will stimulate the appetite abnormally and cause definite hunger cravings in a baby just like it does for us. It's nutritionally bad for a person, too - these days all the expert nutritionists are advising that people avoid all foods containing any high fructose corn syrup which is what Karo syrup is!! (I remember my mother in Alabama cooking with Karo when we were little and no one knew any better....sigh.)
I also agree with the moms here who rightly pointed out to AVOID the rice cereal and rice products, with your daughter having ANY tendency to constipation (again, can't believe the doctor actually recommended it KNOWING she was having the problems!). We never gave my daughter rice cereal except one time when she had a virus with diarrhea, and she refused to eat it (I don't blame her, baby rice cereal is gross!).
Rice, bananas, processed applesauce and sometimes green peas are almost always binding foods, so I would NOT add those to her diet for some time, once you do begin solids. At her age it's a bit young to be starting them anyway - especially since she already has digestive issues. If she seems hungry, I would be more concerned with the quality of her food than the quantity - make sense? Just like with us, we can overeat because what we are eating isn't that great and it's not satisfying our needs, so we feel unsatisfied and keep looking for more.
In my experience there's a lot of societal pressure to push babies into solid foods WAY too early when their little systems are still not very prepared to digest them - it's outmoded thinking from previous generations. Starting solids younger than a year is simply to give babies practice in developing the skills needed to eat actual foods, not to supplement their nutritional needs (although of course as moms we want to give them healthy choices when we do feed them more). Babies are actually designed to get all the complete nutrition they need for the entire first year of life through having breastmilk. It benefits them immensely to nurse the 2nd year as well both nutritionwise and with immunities, but I know in our country it's not very well supported for moms to continue with extended-nursing (even calling it "extended" implies that it's outside the norm!).
That being said, I'm sorry breastfeeding didn't work out to be an option for you and your baby - I know it can be tough when you work outside the home. :( We had to supplement with formula for a while when my daughter was very little and it was nothing but digestive problems for her, and a big pain for me to always be preparing as well, so you have my sympathies. One of the best days of her AND my life together was when she was finally exclusively breastfeeding again at about 3 months! The digestive issues dramatically subsided at that point and in fact her stools got more on the loose side, which was normal for a breastfed baby. The formula product that ended up being least problematic for her was Nestle Good Start (as some other moms have mentioned I believe). You might also look into trying out a lactose-free formula as others have mentioned, if you think she might have issues with cow's milk based products.
When you do start solids, it's not necessary or even nutritious to begin with those pasty old cereals anyway - that's outdated information and I wish it would die out for our poor babies' sakes. Good first foods (especially with an already-overtaxed immature digestive system) can include pureed sweet potatoes, avocado (less likely to appeal to a baby flavorwise but the texture is nice), carrots, squash, green beans, things like that. It's very good to start with veggies and work through several different ones (being sure there are no bad reactions) and then start adding fruits like peaches (pretty laxative due to the water content and VERY sweet and yummy so babies usually love them) and pears. If she still struggles with constipation, baby prunes are good, or mix them with a portion of applesauce if you think the straight prunes are "too much" for her (the prunes will counteract the binding properties of the applesauce).
Pureed meats are good to add eventually, for iron (since she's not BF) and also to get her used to a variety of tastes and textures.
With the constipation issues, I'd stay FAR away from crackers, pasta, cookies, breads, all those starchy foods and anything highly refined until she is older - plus she'll get a much more nutritious and balanced diet without all that starchy filler stuff anyway. If and when you do try baby cereal and bread, I'd keep to oatmeal (or maybe barley if you like it better) and add some fruit to it to make it palatable and give more fiber, and I'd stick to whole wheat bread (any other kind will tend to "stop up the works").
As I mentioned, as an infant my daughter went through a period of having some constipation and what our ped (who IS very up to date I'm happy to say and is a mom of little girls herself) recommended was to offer her a bottle with several ounces of spring water with a single ounce of mild juice in it. White grape juice is the most easy on the digestion for a baby, apple is not bad IF DILUTED (not full strength juice), and we even got some of that baby "apple-prune" juice at one point and would put ONE ounce of that in the water. We ALWAYS used mostly water, the juice simply flavored it so she would drink it well and the small quantity of the juice also had a laxative effect but in a healthy non-traumatic way.
Hope this helped - good luck and I really hope your baby girl is feeling MUCH BETTER very soon; constipation is very rough to deal with and the sooner it's eradicated, the better, so she can relax and be happier.
Blessings,
S.