could 2oz formula have made my breast-fed newborn ds constipated?

[zebralegs]

My 5wk old ds has been almost entirely breastfed since birth, with the exception of 2oz of formula which we gave him yesterday evening. Normally, he does around 2 large-ish poos every day, and has numerous smaller dirty nappies as well. Since the bottle, he has basically had a tiny smudge of poo in one nappy... and that's it. Seems to be in a fair bit of discomfort too Weeing as usual.

I'm guessing it must be the formula? It just seems like such a small amount to have caused him such a problem! Does this mean I can't give it to him in future? Wasn't planning to often, but would like the option...

Also, any ideas how I can ease his discomfort? And at what point do I need to worry if he still hasn't had a proper dirty nappy?

Thanks.

Hi, I know this was posted a few days ago, but seen as no-one has answered I thought I'd say the same thing happened with my DD.

Any formula made her constipated for a few days (and we tried a few brands) and the same thing happened when we started weaning at 6 months.

She is still breast-fed now at 7 months but is eating solid food fine and can take the odd bottle of formula without it causing too much ill effect. She has been prescribed lactulose for occasional use and probably has about 3 doses a week, when she hasn't gone for a couple of days.

I think some babies (anecdotally, usually breast-fed babies) are just prone to constipation and it usually gets better as they get older. Hth :)

My ds (mixed fed) was always the same with formula, and seemed worse when we changed from ready made to powder or switched brands. He was never ebf so can't be sure he wouldn't have these problems anyway, but my instincts say it's the formula. Tummy massages and leg cycling helped. Changing bottles and gaviscon and other colic related ideas did nothing. He's now weaning and it has gotten better with time - just the odd bout now.