Peanut Allergy:
Emergency Action Plan (UK)

Key Facts

• Affects approximately 1–2% of people in the UK
• Persists into adulthood in around 80% of cases
• Leading cause of food-induced fatal anaphylaxis
• Reactions can occur from trace exposures as small as 1.6 mg of peanut protein

High-Risk Groups

• Individuals with co-existing asthma (especially poorly controlled)
• Adolescents and young adults (highest fatality rate)
• Those with high Ara h 2-specific IgE levels
• Patients with previous severe anaphylactic reactions

Important Note

Peanuts are not tree nuts — they are legumes. However, many people with peanut allergy are also advised to avoid tree nuts due to the risk of cross-contamination in processing and manufacturing. Your allergist will advise on an individual basis.

▲ Mouth & Throat

• Tingling or itching of lips, mouth, or tongue
• Swelling of the lips, tongue, or throat (angioedema)
• Hoarse voice or change in voice quality
• Difficulty swallowing or choking sensation

▲ Breathing

• Shortness of breath or rapid breathing
• Wheezing or audible wheeze
• Chest tightness or chest pain
• Persistent or worsening cough

▲ Circulation

• Feeling faint, dizzy, or light-headed
• Rapid, weak, or irregular pulse
• Pale, grey, or clammy skin
• Collapse or loss of consciousness

▲ Skin

• Widespread urticaria (hives)
• Flushing or generalised redness
• Intense itching of skin
• Localised or spreading swelling

▲ Gut & Other

• Nausea, vomiting or stomach cramps
• Diarrhoea
• Sense of impending doom
• Confusion or agitation (especially in children)

Stop eating immediately

If peanut ingestion is suspected, stop eating at once. Do not attempt to induce vomiting. Spit out any remaining food if possible. Call for help from anyone nearby.

Alert someone nearby

Tell a colleague, family member, or bystander that you have eaten peanut and may be having an allergic reaction. Tell them where your adrenaline auto-injector is kept. Do not remain alone.

Choose the correct position

Lie flat with legs raised if you feel faint or dizzy. Sit upright if you have breathing difficulties. Recovery position (on your side) if unconscious or vomiting. Never stand up suddenly during a severe reaction — this can cause sudden cardiac arrest due to a severe drop in blood pressure.

USE YOUR ADRENALINE AUTO-INJECTOR if ANY of these are present:

• Throat tightness, hoarse voice, stridor, or difficulty swallowing
• Shortness of breath, wheeze, or persistent cough
• Chest tightness or pain
• Feeling faint, dizzy, or about to collapse
• Rapid spread of urticaria with any airway or circulatory feature
• Rapidly worsening or severe multi-system reaction

Inject into the outer mid-thigh. Can be given through clothing. Hold for 10 seconds. Note the time of injection.

Call 999 immediately after using adrenaline

Say: “I am having a severe allergic reaction (anaphylaxis) to peanut. I have used my adrenaline auto-injector. I need a paramedic ambulance.” State your exact location. Even if symptoms improve, you must go to hospital. Do not drive yourself.

Second dose of adrenaline if no improvement after 5 minutes

If symptoms do not improve or worsen within 5 minutes, use your second adrenaline auto-injector in the opposite thigh. Per RCUK 2021 guidelines, repeat intramuscular adrenaline at 5 minutes is appropriate where the clinical picture does not resolve. Always carry two auto-injectors — this is an MHRA requirement for all patients prescribed these devices.

For mild reactions only — antihistamine

If the reaction is mild and limited to skin symptoms only (e.g. itching, limited urticaria) without any airway, breathing, or circulatory involvement, a non-sedating antihistamine (cetirizine 10 mg, loratadine 10 mg, or fexofenadine 120 mg) may be appropriate. Antihistamines must never be used instead of adrenaline where anaphylaxis features are present. They are slow-acting and will not prevent anaphylaxis from progressing. Monitor closely for any deterioration and follow your personalised written plan from your allergy specialist.

1

Remove device from carrier tube. Pull off the safety cap (blue cap on EpiPen; yellow on Jext).

2

Grip firmly in dominant hand. Do not place thumb over the tip.

3

Press needle end firmly against the outer mid-thigh. Can be given through clothing.

4

Push until a click is heard or felt. Hold firmly for 10 seconds.

5

Remove and massage gently. Hand the used device to paramedics. Do not re-cap the needle.

Clinical History

Detailed account of all previous reactions — nature, timing, severity, and circumstances. Assessment of co-existing conditions (asthma, eczema, hay fever) which influence risk stratification.

Skin Prick Testing

Standardised peanut extract applied to the forearm. A rapid, safe, and sensitive first-line test. Results available within 15–20 minutes. Performed by a trained specialist nurse or allergist.

Specific IgE Blood Tests

Total peanut-specific IgE (f13). Component testing including Ara h 2 — the most accurate single diagnostic marker for true peanut allergy in the UK. High Ara h 2-sIgE correlates with severe reactions.

Molecular Allergy Testing

ALEX (300 allergen components) or ISAC molecular testing profiles the full range of peanut proteins including Ara h 1, 2, 3, 6, 8, and 9. Distinguishes true peanut allergy from birch pollen cross-reactivity (Ara h 8), preventing over-diagnosis and unnecessary avoidance.

Supervised Food Challenge

A double-blind placebo-controlled food challenge (DBPCFC) remains the gold standard for confirming or excluding peanut allergy. Conducted in our fully equipped clinic under close medical supervision with resuscitation facilities. May be used to confirm diagnosis or assess resolution of allergy.

Baseline Tryptase

Serum tryptase measurement helps identify underlying mast cell disorders (e.g. mastocytosis), which significantly increase anaphylaxis risk and may influence treatment decisions, including prescription of omalizumab alongside oral immunotherapy.

Who is Eligible?

• Children and adolescents aged 4–17 with confirmed IgE-mediated peanut allergy
• Diagnosis confirmed by food challenge, skin testing, and/or Ara h 2 testing
• Well-controlled or no asthma (active asthma is a contraindication)

What to Expect

• Multiple supervised clinic visits during escalation and up-dosing phases
• Daily home doses between visits
• Common side effects: mild oral or GI symptoms during dose increases
• Adrenaline auto-injector must always be carried throughout treatment

Omalizumab (Xolair) Add-On

• EAACI 2025 guidelines suggest omalizumab for IgE-mediated food allergy in children from age 1 and adults as an immunomodulatory option
• Combination with OIT may improve safety and speed of desensitisation in highly sensitive patients
• Discussed individually at specialist consultation

Reading Labels

• Always read the full ingredient list, not just allergy summaries
• Look out for alternative names: groundnut, monkey nut, mixed nuts, arachis oil, beer nuts
• “May contain peanut” or “made in a factory that handles peanuts” warnings are voluntary and indicate genuine cross-contamination risk
• Re-read labels every time — recipes change without notice

Eating Out Safely

• Always inform waiting staff and kitchen of your allergy before ordering
• Ask to speak to the manager or chef for high-risk dishes
• Be particularly cautious with Asian, Middle Eastern, and African cuisines where peanut is used extensively
• Carry written allergy cards — available free from Allergy UK

Hidden Sources of Peanut

• Satay sauces, noodle dishes, stir-fries
• Baked goods, cereal bars, and flapjacks
• Some cooking oils, salad dressings, and marinades
• Some cosmetic products (e.g. certain baby lotions) — inhalation/skin contact risk

Always Carry

• Two in-date adrenaline auto-injectors
• Non-sedating antihistamine tablets
• Your personalised written emergency action plan
• MedicAlert or similar medical ID bracelet or card

For Schools (Children)

• Provide the school with a copy of the child’s written emergency action plan, signed by your allergy specialist
• Ensure the school holds two spare adrenaline auto-injectors in an accessible, clearly labelled location
• Ensure relevant staff (teachers, lunchtime supervisors, sports coaches) are trained in recognition and use of the auto-injector
• Update the plan and device supply at the start of each academic year
• Schools in England may hold a spare adrenaline auto-injector for emergency use under the Human Medicines Regulations 2017 amendment

For Adults (University / Workplace)

• Inform your employer or university disability/health team of your allergy and emergency plan
• Keep a spare auto-injector in a secure but accessible location at your desk or workplace first-aid point
• Consider a MedicAlert bracelet or wallet card — essential if you are alone or unconscious
• Register with Allergy UK’s free allergy alert service for dining and travel
• Review your plan with your allergy specialist at least annually or after any reaction

My child tested positive for peanut IgE but has never reacted. Do they have peanut allergy?

Not necessarily. Sensitisation (a positive IgE test) does not equal clinical allergy. In the UK, many children test positive but are not genuinely allergic. Component testing, particularly for Ara h 2, and a supervised food challenge are essential to establish whether your child has true peanut allergy and to define their threshold of reactivity. An allergy specialist assessment is strongly recommended before placing any child on a peanut-free diet.

Is Palforzia® available privately in London? Who can prescribe it?

Yes. Palforzia® is available privately at specialist allergy clinics with appropriate facilities and trained staff. The BSACI 2024 guidance sets out the clinical and infrastructure requirements for prescribers. At the London Allergy and Immunology Centre, our consultants can assess eligibility, obtain informed consent, and administer the full treatment programme. A detailed pre-treatment workup including food challenge and molecular testing is required before starting.

Can adults develop peanut allergy for the first time?

Yes, though it is less common than childhood-onset peanut allergy. Adult-onset peanut allergy does occur and can present de novo without any prior childhood reactions. Any adult experiencing unexplained urticaria, angioedema, or anaphylaxis following peanut ingestion should be referred to an allergy specialist for full assessment.

Do I need to avoid all tree nuts if I have peanut allergy?

Peanuts are botanically a legume, not a tree nut. However, co-sensitisation to tree nuts is common, and cross-contamination during food manufacturing is a real risk. Whether you need to avoid tree nuts depends on the results of your individual allergy testing. Many people with peanut allergy can safely eat some or all tree nuts. Your allergy specialist will advise based on your test results and clinical history.

My child is due to start peanut OIT. Should they still carry an adrenaline auto-injector?

Yes, absolutely. Throughout the entire course of peanut OIT — including during the maintenance phase — patients must continue to carry two adrenaline auto-injectors at all times. OIT raises the threshold of reactivity but does not eliminate the risk of anaphylaxis. Reactions can still occur, particularly during dose escalation, with exercise after dosing, or during intercurrent illness. Your allergy specialist will review auto-injector requirements at each clinic visit.