Oral immunotherapy for peanut allergy
Peanut allergen extract
An oral immunotherapy that gradually exposes the body to peanut protein to reduce the severity of reactions in peanut allergy.
What is Peanut allergen extract?
Peanut allergen extract is an oral immunotherapy for people with peanut allergy. It contains carefully measured peanut protein, taken by mouth each day, gradually building up so the body becomes less reactive over time. The aim is to reduce the severity of reactions if peanut is eaten by accident, not to cure the allergy or allow free eating of peanuts. The key thing to understand is that the treatment itself can cause allergic reactions, including severe ones (anaphylaxis), which is why it is started and increased under specialist supervision and continued with care. Avoiding peanuts and carrying emergency treatment remain essential.
Education and reference only. This is a plain-language guide to Peanut allergen extract — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Peanut allergen extract is a treatment known as oral immunotherapy, used in people with a confirmed peanut allergy. It contains a defined amount of peanut protein in a form taken by mouth, usually mixed into soft food. The treatment is built up in stages, with the amount increased step by step under specialist care until a maintenance level is reached, then continued daily. Its purpose is to make the body less sensitive so that an accidental exposure to peanut causes a less severe reaction. It is a specialist treatment that does not remove the need to avoid peanuts.
How it works
The treatment works by exposing the immune system to small, gradually increasing amounts of peanut protein over time. This regular, controlled exposure trains the immune system to react less strongly to peanut, a process sometimes described as building tolerance. The aim is that, after building up and continuing the daily maintenance dose, an accidental mouthful of peanut is more likely to cause a milder reaction than before. Because the body is being deliberately exposed to the very thing it is allergic to, reactions are part of how the treatment behaves, especially when the amount is being increased, which is why each increase is done under supervision.
Company & origin
Originated / developed by: Specialist manufacturer.
A specialist oral immunotherapy used in the UK to reduce the severity of reactions in people with peanut allergy, started and built up under specialist supervision.
Practical use
How to take Peanut allergen extract
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it by mouth every day exactly as directed, usually mixed into a small amount of soft food.
- Have each increase in the amount done under specialist supervision, as reactions are most likely then.
- Keep avoiding peanuts and carry your adrenaline auto-injector, as this treatment reduces but does not remove the risk.
- Avoid exercise, hot baths and dosing on an empty stomach around the time you take it, as these can make reactions more likely.
- Tell your specialist team if you are unwell or have a reaction, as the plan may need adjusting.
Weighing it up
Advantages & disadvantages of Peanut allergen extract
Advantages
- Can reduce the severity of reactions if peanut is eaten by accident.
- Offers an active treatment option for peanut allergy rather than avoidance alone.
- Taken by mouth at home once each increase has been done under supervision.
Disadvantages
- Frequently causes allergic reactions, including, at times, severe reactions such as anaphylaxis.
- Reduces but does not cure the allergy, so peanut avoidance must continue.
- Is a long-term daily commitment that must be started and built up under specialist supervision.
Practical use
Good to know
The single most important point is that this treatment can itself cause allergic reactions, including severe ones such as anaphylaxis, because it deliberately gives peanut protein to someone allergic to it. Reactions are most likely when the amount is first given or increased, which is why each step up is done in a specialist setting where reactions can be treated. The goal is to reduce the severity of accidental reactions, not to cure the allergy or to let the person eat peanuts freely, so strict peanut avoidance and carrying an adrenaline auto-injector must continue. Certain things, such as exercise, illness or an empty stomach around dosing, can make reactions more likely, so there are rules about how and when to take it. It is a long-term, ongoing commitment, and stopping can let sensitivity return.
Who should not take it / use with caution
- People with severe or poorly controlled asthma are generally not suitable, as it raises the risk of serious reactions.
- People who have had certain very severe reactions may not be suitable, under specialist judgement.
- It must only be started and built up under a specialist allergy service.
Monitoring
- Carrying out each increase in the amount in a supervised setting where reactions can be treated.
- Reviewing how well it is tolerated and whether reactions are occurring.
- Checking that peanut avoidance and emergency adrenaline are still in place throughout.
Side effects
- Allergic reactions such as itching, tingling in the mouth, tummy pain, hives or wheezing.
- Severe allergic reactions (anaphylaxis), which can happen and need emergency adrenaline.
- Tummy upset that can sometimes persist and occasionally leads to stopping treatment.
Key interactions
- Exercise, hot baths, illness and an empty stomach around dosing can increase the chance of a reaction.
- Some medicines, such as beta-blockers, can affect how an allergic reaction is treated, so tell your team.
- It does not replace your adrenaline auto-injector, which must always be carried.
Available as: Measured amounts of peanut protein taken by mouth, usually mixed into soft food.
Answers
Peanut allergen extract: frequently asked questions
What is peanut allergen extract used for?
It is an oral immunotherapy that gradually exposes the body to peanut protein to reduce the severity of reactions if peanut is eaten by accident in people with peanut allergy.
Does it cure peanut allergy?
No. It reduces the severity of accidental reactions but does not cure the allergy, so peanut avoidance and carrying emergency adrenaline must continue.
Can the treatment itself cause a reaction?
Yes. Because it deliberately gives peanut protein, it can cause allergic reactions, including severe ones, especially when the amount is increased, which is why this is done under supervision.
Can I eat peanuts once I am on it?
No. The aim is to make accidental exposures less severe, not to allow eating peanuts, so strict avoidance still applies.
Why do I have to avoid exercise around dosing?
Exercise, hot baths, illness and an empty stomach around the time of dosing can make a reaction more likely, so there are rules about how and when to take it.
Authoritative sources
- BNF
- NICE CKS
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