7 week old baby lost weight

[Rose05202224]

My baby is now 7 weeks. Her birthweight was 8lbs. She had now dropped almost 2 percentiles below what she should be. She was 9lb8oz last week and within the following week had dropped to 9lb6oz, so lost 2oz. The HV thinks she has a milk allergy due to a mild rash on her abdomen and face. Apart from this she is a very settled and content baby with no issues. She has an element of reflux and would bring up milk after feeding occasionally, although not enough to warrant weight loss IMO. She is formula fed with aptamil comfort due to intermittent constipation. My GP doesnt think she has a milk allergy as she is so content and sleeps well etc. She only cries when she is tired/hungry. Has anyone else been through this and have any other suggestions as to why she could have weight loss?

Was she weighed on the same scales at the sane time of day in the sane place OP?

We had a blip where DC2's weight was recorded incorrectly at the baby clinic.

I agree that it would be unusual for a baby with CMPA or indeed any allergy to he so content. Not sure what woukd be causing the rash though, is it where the nappy sits?

What has the HV suggested?

Thanks so much for getting back to me. Yeah they were the same scales and it was around the same time. I know 2oz isn't a massive drop but she's now gone from the 75th centile to just above the 9th. She is so content and never cries unless hungry or tired. The abdominal rash was assumed either viral infection or prickly heat. Its all over the abdominal area.
My HV recommended using a prescription lactose free milk. I am very reluctant to start that as last weekend she was put on gaviscon as they were concerned the reflux was maybe causing weight loss. She was extremely unsettled on this so stopped it. The GP was reluctant to prescribe it but did it anyway as the HV suggested it.

She could be allergic to lactose but that would be exceptionally rare.

Did the HV say why she thought it might be the lactose bothering your LO and not the protein in the milk which is a much more common allergy, affecting about one in ten babies?

Sorry I meant to say cows milk protein not lactose.

My friend has had two cmpa babies the first screamed for 8 weeks and only settled after starting on DF formula. Her second was a super happy content baby and only diagnosed when he started with explosive nappies after switching to formula which stopped on the hypoallergenic formula

I would ask for omperazole to see if the reflux is responsible for the weight loss. It might be that they aren't feeding as much as they are in discomfort from the reflux and possible cmpa. I would say the slow weight gain is enough on its own to trial a dairy free formula. My daughter was on the 9th percentile until I went dairy free and then she moved up to the 25th-50th percentile. She wasn't diagnosed until 17 weeks as it took until then for her to get exceptionally unhappy but her symptoms started at a week old with a rash which the GP always put down to viral but it never went and now she gets the same rash as a reaction, slow weight gain which was attributed to her just being a small baby, reflux which according to the GP was "just a washing problem" and loose stools which weren't picked up as I was just asked if they were normal and not what they were like. They had always been the same so they were normal for all which isn't the same as normal - ftm and lockdown so I didn't see anyone who also had a baby or any grandparents aunts uncles with children

The constipation can be an allergy sign. It can cause either loose stools or constipation

I think this is very good advice.

If you've been offered milk suitable for a baby with CMPA i would definitely try that