Xolair (omalizumab) versus other medications for food allergy and hives is an increasingly important comparison as biologic treatments become more widely available in the UK. Xolair is a monoclonal antibody that targets immunoglobulin E (IgE), offering a targeted approach distinct from standard antihistamines or immunosuppressants. For chronic spontaneous urticaria (CSU), it is NICE-approved for refractory cases, while its use in food allergy remains unlicensed in the UK despite recent FDA approval in the US. Understanding how Xolair compares with other options helps patients and clinicians make informed, shared decisions about the most appropriate treatment pathway.

How Xolair Works for Food Allergy and Chronic Hives

Xolair (omalizumab) is a biological medicine — specifically a monoclonal antibody — that targets immunoglobulin E (IgE), a key driver of allergic reactions. In people with allergies, IgE binds to mast cells and basophils via high-affinity IgE receptors (FcεRI), triggering the release of histamine and other inflammatory mediators that cause symptoms such as hives (urticaria), swelling, and, in severe cases, anaphylaxis. Omalizumab works by binding to free IgE in the bloodstream, preventing it from attaching to these immune cells. Over time, this also leads to down-regulation of FcεRI on mast cells and basophils, further dampening the allergic cascade.

For chronic spontaneous urticaria (CSU) — a condition characterised by persistent, unpredictable hives lasting more than six weeks — Xolair is licensed in the UK and approved by the European Medicines Agency (EMA) for use in adults and adolescents aged 12 and over whose symptoms are inadequately controlled by antihistamines.^[1][2] It is worth noting that CSU is not always driven by IgE-mediated mechanisms, yet omalizumab can still be effective, likely through modulation of the IgE pathway and FcεRI down-regulation. By reducing free IgE levels, it significantly lowers the frequency and severity of hive outbreaks.

Regarding food allergy, the picture is more nuanced. In early 2024, the US Food and Drug Administration (FDA) approved omalizumab to reduce allergic reactions to accidental food allergen exposure in patients aged one year and older. However, as of the time of writing, this specific indication has not been approved by the MHRA or EMA for use in the UK. Patients and clinicians should note that Xolair is not a cure for food allergy and does not replace allergen avoidance or the need to carry emergency adrenaline auto-injectors.^[1][3] Those interested in this potential use should discuss it with a specialist, as the regulatory position in the UK may evolve.

Comparing Xolair with Antihistamines and Other Standard Treatments

The standard first-line treatment for chronic hives in the UK, as outlined by NICE, the British Association of Dermatologists (BAD), and the British Society for Allergy and Clinical Immunology (BSACI), is a non-sedating second-generation antihistamine such as cetirizine, loratadine, or fexofenadine. These medications block histamine H1 receptors and are effective for many patients, particularly at licensed or up-dosed levels (up to four times the standard dose, used off-label under specialist guidance).^[3] They are widely available, inexpensive, and generally well tolerated, making them the logical starting point for most people. In UK practice, validated tools such as the Urticaria Activity Score over 7 days (UAS7) and the Urticaria Control Test (UCT) are commonly used to assess symptom burden and guide decisions about escalating treatment.

When antihistamines fail to provide adequate symptom control — even at higher doses — clinicians may consider stepping up treatment. Options at this stage can include:

• Short rescue courses of oral corticosteroids (e.g., prednisolone) for acute flares only; long-term use is not recommended in CSU due to significant risks including weight gain, osteoporosis, and adrenal suppression

• Ciclosporin, an immunosuppressant used off-label in refractory CSU, which requires careful monitoring of renal function and blood pressure^[3]

• Omalizumab (Xolair), which represents a targeted, biologic alternative with a more favourable safety profile than long-term immunosuppressants

For food allergy specifically, standard management relies on strict allergen avoidance, patient education, and access to emergency medication. In the event of a severe allergic reaction or suspected anaphylaxis, an adrenaline auto-injector (such as EpiPen or Jext) should be used immediately and 999 called without delay — even if symptoms appear to improve.^[3] Antihistamines are adjunctive only and must never be used as a substitute for adrenaline in a severe reaction.^[3] Oral immunotherapy (OIT) is an emerging approach for certain food allergies (notably peanut allergy in children), but it carries its own risk profile, must only be undertaken in specialist centres, and has limited availability on the NHS.

Effectiveness and Safety: What the Evidence Shows

The evidence base for omalizumab in chronic spontaneous urticaria is robust. Pivotal phase III clinical trials — including the ASTERIA I, ASTERIA II, and GLACIAL studies — demonstrated that omalizumab at 300 mg every four weeks produced significant reductions in itch severity scores and hive activity compared with placebo. A meaningful proportion of patients achieved complete symptom resolution. These findings supported its EMA approval and subsequent NICE guidance (TA339) for use in refractory CSU.^[2]

For food allergy, the landmark OUtMATCH trial (published in the New England Journal of Medicine, 2024) showed that omalizumab significantly reduced allergic reactions to accidental exposure to peanut, tree nuts, milk, and egg in participants aged 1–55 years. Approximately 67% of omalizumab-treated participants could tolerate a 600 mg peanut protein dose without a reaction, compared with 7% in the placebo group. While these results are clinically significant, this evidence informed the FDA approval; UK regulatory bodies have not yet granted the same indication.

In terms of safety, omalizumab is generally well tolerated. Common adverse effects include:

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• Injection site reactions (redness, swelling, bruising)

• Headache and fatigue

• Nasopharyngitis (common cold-like symptoms)

• Arthralgia (joint pain), as listed in the UK Summary of Product Characteristics (SmPC)

Patients with a high risk of parasitic (helminth) infections should discuss this with their specialist before starting treatment, as omalizumab may affect immune responses to such infections.^[1][2]

A rare but serious risk is anaphylaxis, which can occur at any point during treatment — including beyond two hours after injection and after many previous doses without incident.^[1][2] Patients should be counselled to recognise symptoms such as throat tightening, difficulty breathing, or dizziness, and to seek immediate medical attention if these occur. Observation periods following injection are determined by local clinical protocols and individual patient risk assessment.

Omalizumab may be administered by a healthcare professional in a clinic setting, or by the patient or a trained caregiver at home after appropriate training, if deemed suitable — in line with the UK SmPC.^[1][4] Patients and healthcare professionals should report any suspected side effects via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk or via the Yellow Card app).

Practical Considerations: Dosing, Access, and NICE Guidance

In the UK, omalizumab for chronic spontaneous urticaria is administered as a subcutaneous injection of 300 mg every four weeks. The dose is fixed for CSU, unlike its use in asthma where dosing is weight- and IgE-level dependent. Injections may be given by a healthcare professional in a specialist setting such as a dermatology or allergy clinic, or by the patient or a trained caregiver at home after appropriate training, subject to clinical assessment and local protocols.

NICE Technology Appraisal TA339 recommends omalizumab as an option for treating severe CSU in adults and young people aged 12 and over, provided it is used within its licensed indication and the patient's condition has not responded adequately to standard antihistamine therapy.^[1][2] In UK practice, treatment response is typically assessed using validated tools such as the UAS7 and UCT at around 12–16 weeks. If there is no meaningful improvement, discontinuation is recommended in line with NICE TA339 and local commissioning policies. Access is through specialist referral — usually to a dermatologist or clinical immunologist — and treatment is funded by the NHS when NICE criteria are met. Periodic reassessment is recommended to determine whether ongoing therapy remains necessary, and some patients with CSU experience sustained remission after stopping treatment.^[1][2]

For patients with food allergy, access to omalizumab for this indication is currently not routinely available on the NHS, as UK regulatory approval has not been granted. Some patients may be eligible for clinical trials or named-patient programmes, which should be discussed with a specialist.

Regarding cost, the BNF lists omalizumab (150 mg per pre-filled syringe) at a published list price; actual NHS costs may differ due to procurement arrangements.^[3] Patients seeking specific pricing information should consult the current BNF or discuss with their specialist team. The substantial cost of omalizumab makes NHS commissioning decisions particularly important.

Talking to Your Specialist About the Right Treatment for You

Choosing between omalizumab and other treatments is not a one-size-fits-all decision. It depends on the nature and severity of your condition, your response to previous treatments, your overall health, and practical factors such as your ability to attend regular clinic appointments or undertake self-injection after training. A frank, informed conversation with your specialist — whether a dermatologist, allergist, or clinical immunologist — is the most important step in finding the right approach.

If you have chronic hives, it is worth discussing:

• Whether your antihistamine dose has been optimised (including up-dosing under medical supervision)

• How significantly your symptoms affect your quality of life, sleep, and daily functioning — your specialist may use tools such as the UAS7 or UCT to assess this

• Whether you have tried and not responded to other treatments such as ciclosporin

• Any concerns about injection-based treatments or clinic attendance

You should seek urgent medical attention if you develop airway-threatening swelling (angioedema), systemic symptoms such as dizziness or collapse, or hives that are worsening rapidly despite treatment. These may indicate a need for emergency care or prompt specialist review.

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If you have a food allergy and are interested in omalizumab, be open with your specialist about your expectations. It is essential to understand that, in the UK, this use is not currently licensed and that omalizumab does not eliminate the risk of severe reactions. Allergen avoidance and carrying an adrenaline auto-injector at all times remain non-negotiable safety measures. In the event of a severe allergic reaction, use your adrenaline auto-injector immediately and call 999 — do not wait to see if symptoms resolve on their own. Ensure you and those around you are trained in how to use your device, and carry a written emergency action plan.

You should contact your GP or specialist promptly if your hives are worsening despite treatment, if you experience a severe allergic reaction, or if you develop new symptoms that concern you. For those already receiving Xolair, report any unusual reactions after injections immediately, and report suspected side effects via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk). Shared decision-making — where your preferences and values are considered alongside clinical evidence — is central to good allergy and dermatology care in the UK, and you are entitled to ask questions and seek a second opinion if needed.

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