House dust mite extracts

How it works

Controlled repeated allergen exposure induces immunological tolerance, modulating allergen-specific T-cell responses and promoting protective blocking IgG antibodies while dampening IgE-mediated reactions.

Prescribing in practice

• Systemic allergic reactions including anaphylaxis can occur, so treatment must be initiated under specialist supervision with resuscitation facilities available and an appropriate observation period after dosing.
• Should only be prescribed and supervised by clinicians experienced in allergen immunotherapy after confirmation of clinically relevant mite sensitisation.
• Use with caution in unstable or severe asthma, which raises the risk of serious systemic reactions; consult the SPC for the individual product.

Monitoring

Monitor for immediate and delayed allergic reactions, with particular vigilance at treatment initiation and dose escalation.

Counselling the patient

• Mild mouth itching or local swelling is common early in treatment and usually improves over time.
• Get emergency help for breathlessness, wheeze, widespread rash, or swelling of the face or throat.
• Treatment is taken regularly over a prolonged period and the full course is needed for lasting benefit.

Evidence & guidelines

Allergen immunotherapy for house dust mite allergy is endorsed by international allergy guidelines, with NICE recognising it for selected patients with severe persistent allergic rhinitis inadequately controlled by conventional treatment.