Y.B.
Hi P.,
I just went through the same thing with my daughter. She is now 7 months but several weeks ago she was VERY constipated. My husband and I did a little research and found the following advice (from Dr. Sears Baby Book):
1) remove binding foods from diet - example bananas, apples, also cereals usually have a lot of iron so this binds as well
2) if that doesn't help, add foods the loosen - peaches, pears, apricots, prunes, plums (my daughter had an allergic reaction to prunes, but pears and peaches helped a lot).
Water, apple juice are also good to add to diet as well.
3) if neither of 1 or 2 help, you may have to use a laxative/suppository. Unfortunately, we had to go this route. My daughter was so uncomfortable and irratable for a couple of days :( We used 1 pedialax (from drug store) laxative/suppository and we had a BM within 10 minutes. And then our daughter was happy again.
The sad thing is when I called the dr, the lady that I talked to suggested switching from rice to oatmeal, and add apples or prunes.
Well oatmeal had just as much iron as rice and apples bind as well...so I was giving her more things to stop her up. :(
We removed all cereal from her diet for 2 weeks and she was just getting breastmilk, peaches, pears, and veggies. Plus I would try to get her to take apple juice (just an ounce or so a day). And she has been pretty regular ever since.
Now, we don't give her as much cereal with each meal and I make sure that she gets peaches or pears pretty regularly.
I hope this helps and good luck!