Katzenepithelien Hal Allergy (Cat Epithelia)

Katzenepithelien Hal Allergy is an allergen extract used in allergy immunotherapy for cat‑related hypersensitivity.

• Cat allergy: reduces symptoms by inducing immunological tolerance to cat epithelial proteins.
• Cat‑induced allergic rhinitis: helps lessen nasal congestion, sneezing and itching caused by cat exposure.
• Cat‑triggered asthma: supports reduction of bronchial hyper‑responsiveness associated with cat allergens.

• Katzenepithelien Hal Allergy works by delivering controlled amounts of cat epithelial proteins to the skin, which stimulates the immune system to shift from a Th2‑dominant response toward a Th1‑dominant profile. This modulation decreases specific IgE production and promotes regulatory T‑cell activity, leading to long‑term tolerance to cat allergens.

Adverse reactions may occur following cutaneous exposure to the allergen extract.

Common Side Effects

• Local erythema: redness at the application site.
• Pruritus: mild itching where the product is applied.
• Swelling: transient edema of the skin.
• Small papules: formation of tiny raised lesions.
• Mild urticaria: limited hives confined to the treated area.
• Transient warmth: sensation of heat at the site.

Serious or Rare Side Effects

• Systemic allergic reaction: generalized urticaria or angioedema.
• Anaphylaxis: severe, life‑threatening hypersensitivity requiring emergency care.
• Severe dermatitis: extensive skin inflammation beyond the application zone.
• Respiratory distress: bronchospasm or wheezing after exposure.
• Serum sickness‑like reaction: fever, joint pain and rash.
• Cardiovascular collapse: hypotension and shock in extreme cases.

Before initiating therapy, clinicians should evaluate patient history and monitor for reactions.

• Assess severity: confirm cat allergy diagnosis with appropriate testing.
• Asthma control: ensure underlying asthma is well‑controlled before use.
• Concomitant immunotherapy: avoid simultaneous use of other allergen extracts.
• Immunocompromised patients: use with caution in individuals with weakened immune systems.
• Pregnancy and lactation: safety not established; weigh potential benefits against risks.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Allergen extracts may interact with other medications or therapies.

Major Interactions (Avoid)

• Beta‑blockers: may exacerbate anaphylactic reactions and reduce response to epinephrine.
• Systemic immunosuppressants: can diminish the immunologic effect of the extract.
• Other allergen immunotherapies: concurrent use may increase risk of severe systemic reactions.

Moderate Interactions (Monitor Closely)

• Antihistamines: may mask early skin reactions, making monitoring harder.
• NSAIDs: can increase local irritation or urticaria.
• ACE inhibitors: potential for enhanced angioedema in susceptible individuals.