Veterinary Allergy Treatment Strategies

Treatments for Allergy

• Diagnostic steps for a pruritic (itchy) dog or cat need to be determined.
• Matching antipruritic drug mechanisms of action to their respective drugs is required.
• Two side effects for each discussed antipruritic drug/drug class should be listed.
• Choosing an appropriate antipruritic drug for a patient based on factors like animal characteristics, itch season, and client finances is crucial, along with justifying the choice.

Cost of Veterinary Care in 2023

• Skin conditions make up 32% of veterinary care costs.
• Gastritis accounts for 19%.
• Ear infections represent 11%.
• Eye conditions total 7.8%.
• Heart conditions represent 6%.
• Growths and tumors make up 5.5%.
• Seizures account for 5.3%.
• Infections comprise 4.6%.
• Urinary tract infections (UTIs). are 4.6%.
• Liver disease accounts for 3.8%.

Clinical Signs of Allergic Dermatitis

• Common: Bilaterally symmetric, initially lesion-less pruritus, erythema
• Rare: Angioedema, urticaria, anaphylaxis
• Variable presentation across species

Distribution of Lesions

• Images/examples of lesion distribution in animals.
• This includes various forms and areas of skin involvement

Treating Allergic Conditions

• Identify the specific allergic disease(s) present.
• Lifelong conditions require long-term treatment strategies.
• A multimodal treatment approach is often necessary
• Secondary infections need to be addressed.
• Itching and inflammation need to be managed.
• Treatments must be tailored to individual animal.

Clinical Approach to the Pruritic Pet

• Rule out ectoparasites (external parasites)
• Treat secondary infections.
• Break the itch cycle.
• Food trials (if not seasonal triggers).
• Environmental allergy testing/allergy immunotherapy (if needed)
• Antipruritic therapy for long-term management

Treatment

• Long-term conditions require long-term therapies
• Use a multimodal approach.
• Treatments should be customized to each individual animal.
• Threshold of pruritus (itching) needs to be considered.

Allergen-Specific Immunotherapy (ASIT)

• Encourages a Th1 response and increases IFN-γ.

• Promotes IgG to act as a blocking antibody.

• Increases Treg cells to suppress Th2 polarization.

• Decreases Th2 cytokines (like IL-4 and IL-5).

• Decreases inflammatory cells (neutrophils, eosinophils, basophils, mast cells).

• Allergen selection is crucial.

• Subcutaneous or sublingual (under-the-tongue) approaches are used.

• Owner education and compliance are essential.

Glucocorticoids

• Act by stabilizing cell membranes, inhibiting pro-inflammatory cytokines, inhibiting T cell function, decreasing eicosanoids.

• Suppress myeloid cell activities.

• Many potential side effects.

• Contraindicated in patients with previous demodicosis, liver disease, diabetes mellitus, hyperadrenocorticism, cardiac disease, current NSAID use, pregnancy, and lactation.

• Once-daily dosing and tapering protocols are sometimes possible.

• Different formulations of glucocorticoids vary in potency, duration of action, and mineralocorticoid side effects.

Glucocorticoids (Specific Formulations)

• Methylprednisolone acetate (Dep-Medrol®) dosages and/or administration methods are unique (20mg/dog sc).

Side Effects of Glucocorticoids

• Short-term: polyuria/polydipsia (PU/PD) and polyphagia (excessive eating).
• Long-term: muscle wasting, pot-belly, alopecia (hair loss), and diabetes mellitus.

Cyclosporine (Atopica™ / Cyclavance™)

• Inhibits T cell function by blocking IL-2 transcription.
• Side effects include vomiting/diarrhea and gingival hyperplasia.
• Caution when administering with other drugs.
• Contraindicated in animals with a history of neoplasia or renal insufficiency.
• Also contraindicated in pregnant animals, females that are lactating, and animals younger than 6 months of age.

Oclacitinib (APOQUEL®)

• Acts as a JAK inhibitor, influencing IL-2, IL-4, IL-6, IL-13, and IL-31.
• Side effects include vomiting, diarrhea, lethargy, anorexia, and polydipsia.
• Not intended for use in dogs younger than 12 months or those with certain conditions.
• Note caution when use with demodicosis, pregnancy, and lactation.

Lokivetmab (CYTOPOINT®)

• It's a monoclonal antibody neutralizing IL-31.
• Not recommended for use in cats.

Antihistamines

• Mechanism of action: Block H1 receptors.
• Side effects: sedation, hyperexcitability (2nd generation are generally less sedating).
• Caution in cases of liver disease, urinary abnormalities, and digestive issues..
• Not ideal for rapid relief or severe pruritus.
• Potential to reduce the need for corticosteroids.

Others

• Fatty acids help with barrier function, modifying prostaglandins and leukotrienes
• Pentoxifylline a phosphodiesterase inhibitor has multiple anti-inflammatory and immunomodulatory effects.

Outside-In vs. Inside-Out Treatment

• Defective epidermal barriers play a role in allergic conditions and are addressable by topical therapies
• Including topical therapies for skin barrier restoration.

Topical Antipruritics

• Ingredients like hydrocortisone and pramoxine may be beneficial for treating itchiness.
• Short-acting relief; frequent use can be problematic with topical steroids
  • It's key to use topical steroids carefully for the best results.

Topical Barrier Restoration

• Ceramides, fatty acids, and phytosphingosine can help restore skin barriers
• Barrier restoration therapies are generally helpful as adjunctive therapy

Species-Specific Considerations

• Different responses to treatments like Cytopoint and Apoquel may vary between species (dogs vs. cats).
• Antihistamines may be more effective on some species.
• Some treatments aren't suitable for certain species (ie: cats can’t use cytopoint)

Non-Derm Allergic Therapies

• Addressing anaphylaxis with epinephrine, promoting vasodilation or vasoconstriction of vessels.
• Managing allergic respiratory issues and possibly treating other conditions requiring antihistamines or corticosteroids.

Summary

• Allergies are a significant reason for bringing pets to veterinarians.
• Diverse treatment approaches exist; not one is perfect for everyone; however, some are better suited for certain species., so consideration is key.
• Secondary problems like infection and ectoparasites often need treatment, too.

Questions?

• Some general questions relate to allergy protocols and best practices are asked.

Test your knowledge on the primary strategies for treating pruritic pets and managing allergies effectively. This quiz covers essential treatment components, important management steps, and common therapeutic interventions for conditions such as anaphylaxis and asthma. Enhance your understanding of veterinary care for allergies in pets.