1. The signs you’ve noticed

Tick anything you’ve seen. Allergy UK groups signs by how quickly they appear after milk.

Quick reactions (within minutes to about 2 hours)

• Itchy skin, redness or raised red bumps (hives)
• Swelling around the eyes, lips or face
• Being sick or diarrhoea soon after a feed
• A sneezy, runny nose or itchy, watery eyes (without a temperature)

Delayed reactions (from about 2 hours, up to 3 days)

• Long spells of unexplained crying, drawing legs up, unsettled
• Reflux, or bringing up large amounts of feed
• Mucus or blood in poo
• Straining to poo, whether it’s soft, loose or hard
• Eczema that stays inflamed and isn’t improving with treatment
• Rashes that come and go
• Not wanting to feed
• Not putting on weight, or losing weight

2. Write these down before you go

Your GP will ask questions to work out whether an allergy is likely. Having the answers ready makes that much easier.

• Which symptoms you’ve seen, and which worry you most
• When they first started, and how long they last
• How quickly they appear after a feed
• Whether they happen every time
• How your baby is fed: breast milk, formula or both
• If you’ve started weaning, which foods, how much and in what form
• Any food you suspect is a trigger
• Any eczema, asthma, hay fever or food allergy in your baby or close family
• Any medicines or feeding changes you’ve already tried

3. Evidence worth bringing

• A food and symptom diary: what was eaten or fed, when, and what happened after
• Photos of rashes, swelling or nappies that concerned you
• Short videos of how your baby is during or after a feed
• A list of any medicines your baby is taking

This matters most with delayed reactions, because the link to milk is harder to spot.

4. Questions worth asking

• Could this be a cow’s milk allergy, or could something else explain it?
• Do the symptoms look like a quick reaction or a delayed one?
• What are the next steps, and who will guide us through them?
• If you suspect a delayed allergy, how would we check it, and for how long?
• Could we be referred to a dietitian or a children’s allergy service?
• What should we look out for, and when should we come back?

What usually happens next

Your GP will ask about your baby’s symptoms and feeding. If a quick (IgE) reaction is suspected, they will usually refer you to a children’s allergy service for skin prick or blood tests.

For delayed reactions there’s no reliable test. Instead, your GP may suggest removing cow’s milk for a set period, then reintroducing it to see if symptoms return. This should always be guided by your GP or dietitian, so please don’t cut milk out on your own.

NICE advises against tests such as hair analysis, kinesiology or Vega testing, as there’s no evidence they work.