Goat's milk allergy
Allergy to goat's-milk protein.
About goat's milk allergy
Goat's milk allergy is an allergy to the proteins in goat's milk, particularly the caseins, and it can be severe. Some people are allergic to goat's and sheep's milk while tolerating cow's milk, and others react to all three because their proteins are similar. It is an IgE-mediated food allergy: the immune system makes antibodies to the milk proteins, and on later exposure these antibodies drive a fast release of histamine and other chemicals. This differs from lactose intolerance, which is a digestive problem with milk sugar and does not involve the immune system.
Reactions often come on rapidly, within minutes, and can be serious, including anaphylaxis. Symptoms may include hives, swelling of the lips and face, vomiting, wheeze, throat tightness, a drop in blood pressure and collapse, as well as milder skin and tummy upset. Because goat's and sheep's milk proteins closely resemble each other, people allergic to one are frequently advised to avoid both, and there is often, though not always, cross-reactivity with cow's milk.
Diagnosis uses your history with skin-prick or specific-IgE testing, and sometimes a medically supervised challenge. Management is strict avoidance of goat's-milk products, including certain cheeses, yoghurts and some infant formulas, with careful label-reading. Anyone judged to be at risk of anaphylaxis should carry an adrenaline auto-injector. A severe reaction is a medical emergency: use the injector without delay and call 999 in the UK.
Common triggers
- Goat's milk and products containing it
Symptoms
- Itching or tingling in the mouth
- Hives, itching or eczema
- Swelling of the lips, face, tongue or throat
- Stomach cramps, nausea, vomiting or diarrhoea
- Wheezing or trouble breathing
- In severe cases, anaphylaxis
Avoidance & management
- Read ingredient labels every time
- Ask about ingredients and cross-contamination when eating out
- Keep the food out of shared cooking areas
- Carry prescribed antihistamines or an adrenaline auto-injector
- Seek emergency help for any severe reaction
Sources & references
Allergy safety: what everyone should know
Mild-to-moderate reaction signs
- Itching, hives or a raised rash
- Swelling of lips, face or eyes
- Tingling mouth, sneezing, runny nose
- Stomach pain, nausea or vomiting
Anaphylaxis — call 999 (UK) or 112 (EU) immediately
- Difficult or noisy breathing, wheeze, persistent cough
- Swelling of the tongue or tightness in the throat
- Dizziness, collapse, pale and floppy (young children)
- Use an adrenaline auto-injector (e.g. EpiPen) at once if prescribed, then call an ambulance even if symptoms improve
Allergy or intolerance? A true allergy involves the immune system and can escalate quickly; an intolerance (e.g. lactose intolerance) is unpleasant but not life-threatening. The symptoms overlap, so self-diagnosis is unreliable.
Getting tested: home-testing kits based on IgG are not diagnostically valid. If you suspect an allergy, ask a GP for referral to an allergy clinic for skin-prick or specific-IgE testing and a supervised food challenge where appropriate.