Non-IgE CMPA symptoms in babies: the complete checklist

Something feels off with your baby, but you can’t quite put your finger on it. The reflux isn’t settling the way it should. The eczema keeps flaring despite the cream. The nappies look different. They seem uncomfortable, unsettled — not quite right.

When parents come to me concerned about non-IgE CMPA, this is almost always the picture. Not one dramatic symptom, but several smaller things happening at once — none of which, in isolation, would necessarily point to dairy.

This post is a reference you can come back to. It maps the full range of non-IgE CMPA symptoms across different body systems, explains why the pattern matters more than any individual symptom, and gives you something concrete to take to your next GP or dietitian appointment.

Important before you read onThis checklist is for educational purposes. It’s not a diagnostic tool — non-IgE CMPA is diagnosed through a supervised elimination and reintroduction process, not symptom lists alone. Use this as a starting point for a conversation with your GP or paediatric dietitian, not as a substitute for that conversation.

Why non-IgE CMPA often presents as multiple symptoms

Non-IgE CMPA is a delayed immune response — the body’s reaction to cow’s milk protein plays out slowly, across different systems, over hours to days. This is why it so rarely announces itself with a single, obvious symptom.

In my clinical experience, the most reliable signal is seeing three or more symptoms occurring together — particularly when they’re not fully resolving with standard treatments. Eczema alone might mean many things. But eczema alongside constipation and persistent congestion? That combination is worth investigating. (ESPGHAN, 2012)

Symptoms can also shift as your baby grows. What looked like reflux and loose stools at six weeks might become constipation and fussy eating at twelve months. This doesn’t necessarily mean the allergy has resolved — it may simply be presenting differently.

Gastrointestinal symptoms

The gut is where non-IgE CMPA most consistently shows up. These symptoms may be present together, or only some may apply to your baby:

Reflux: Frequent regurgitation or vomiting beyond what seems typical — particularly when it persists despite positioning changes or anti-reflux formula. Especially after introduction to solids. 

Constipation: Hard, pellet-like stools, or straining without producing a bowel movement. In breastfed babies, infrequent stools combined with obvious discomfort. Constipation is more common in toddlers with CMPA than many parents realise.

Diarrhoea or loose stools: Frequent, watery, or unusually loose stools — sometimes with a foamy or frothy appearance.

Mucus in the stool: Visible slime or stringy material in the nappy. Common in FPIAP (Food Protein-Induced Allergic Proctocolitis), a subtype of non-IgE CMPA often seen in younger babies. (ESPGHAN, 2012)

Blood in the stool: Small amounts of blood — often appearing as red streaks or mixed into mucus. In an otherwise well, settled baby, this is a common presentation of FPIAP. Always report blood in the stool to your GP. [See note below]

Bloating and wind: A visibly distended tummy, excessive flatulence, or obvious abdominal discomfort — particularly after feeds.

Vomiting: Beyond normal posseting — forceful or frequent vomiting that’s causing distress or affecting weight gain.

Poor weight gain: Faltering growth or failure to meet expected weight milestones, where other causes have been ruled out.

A note about blood in the stoolIn a well baby — alert, feeding normally, gaining weight — a small amount of blood or mucus in the stool is most commonly associated with FPIAP and is generally not an emergency. However, large amounts of blood, blood in a clearly unwell or distressed baby, or blood accompanied by fever should be assessed urgently by a GP or emergency department. When in doubt, always seek medical review.

Skin symptoms

Skin involvement is common in non-IgE CMPA, though it’s worth noting that eczema and rashes have many possible causes beyond dairy. The signal here is whether skin symptoms are part of a broader cluster, or whether they’re proving difficult to manage despite appropriate treatment.

Eczema: Persistent, inflamed, itchy skin — particularly when it flares despite consistent use of prescribed steroid creams and moisturisers (RCH Non IgE allergy guidelines). Eczema on its own isn’t diagnostic of CMPA, but when it’s part of a symptom cluster and isn’t fully controlled with topical treatment, dairy is worth exploring as a contributing trigger. (ASCIA, 2023). It is worth checking with your GP if triggers are environmental in nature also; like dustmites, mould or grass pollens. 

Rashes or hives (non-immediate): Skin rashes or mild hives appearing hours after dairy exposure — distinct from the rapid-onset hives of IgE allergy.

Redness around the anus: Perianal redness or rash, sometimes seen alongside FPIAP.

Respiratory and ENT symptoms

These symptoms are less commonly discussed in relation to CMPA, but I see them regularly in practice — particularly in older babies and toddlers.

Persistent congestion: A constantly runny or blocked nose without an obvious viral cause. Chronic congestion is a frequently overlooked non-IgE CMPA symptom.

Chronic ear infections: Recurrent otitis media (ear infections), particularly when they’re happening frequently and aren’t clearly linked to illness. This is usually related to an underlying reflux where the fluid has ended up in the ear. 

Enlarged tonsils or adenoids: Seen more often in toddlers. This can be related to GERD symptoms present in the first year of life that later results in paediatric ENT issues. These can range from ear infections (Lee, 2020), reflux causing adenoids enlargement (Nix et al, 2018) as well as recommendations from ENT’s to review reflux management before considering surgical adenoid/ tonsil intervention (Stapleton, 2008).

Behavioural and sleep symptoms

These are often the symptoms that bring parents to the point of exhaustion — and the ones most likely to be dismissed as ‘just a phase’ or ‘some babies are just like this.’ They’re also the hardest to attribute directly to dairy, which is precisely why they’re often last on the list to be investigated.

Excessive crying or irritability: Persistent distress that isn’t settling with feeding, winding, or comfort — particularly if it seems to worsen in the hours after a feed.

Disrupted sleep: Frequent night waking, difficulty settling, or sleep that’s clearly not restful — especially when combined with gut symptoms like reflux or wind.

Back-arching during or after feeds: A sign of discomfort — often associated with reflux or abdominal pain.

Feeding refusal: Reluctance to take a bottle or breast, or pulling away mid-feed — particularly if feeds are associated with discomfort.

Fussy eating (toddlers): Extreme food selectivity, food refusal, or gagging — sometimes associated with ongoing gut discomfort or texture sensitivity.

Do symptoms look different in breastfed vs formula-fed babies?

Non-IgE CMPA can occur in both breastfed and formula-fed babies, but the picture can differ between the two.

In formula-fed babies, cow’s milk protein is present in standard formula in significant quantities, so symptoms can be more pronounced and consistent. Switching to a hypoallergenic formula is the first step in the elimination process. Please refer to the ASCIA website for more specific advice. 

In breastfed babies, cow’s milk protein from the mother’s diet passes through breastmilk in smaller quantities — which means symptoms can be subtler and less consistent. This sometimes leads to delayed recognition, or to breastfeeding being incorrectly ruled out as a factor. (Venter et al., 2017)

Breastfeeding mothers don’t need to stop breastfeeding to trial a dairy elimination — they eliminate dairy from their own diet for four weeks while continuing to feed their baby.

What to do with this checklist

If you’re seeing several of the symptoms listed here — particularly three or more occurring together — it’s worth raising with your GP. Some things that help:

• Note which symptoms your baby has, how frequent they are, and how long they’ve been present
• Track whether symptoms seem to worsen after feeds (particularly useful for formula-fed babies)
• Record whether standard treatments (reflux medication, eczema creams) are providing full relief or only partial relief
• Bring this information to your GP appointment as a basis for discussing whether a supervised dairy elimination is worth trying

Your GP can refer you to a paediatric dietitian who can guide you through the elimination and reintroduction process safely, while ensuring your baby’s nutritional needs are met throughout.