Interview Questions for Allergy Immunotherapy

Allergen-specific immunotherapy (AIT) works by gradually desensitizing the immune system to a specific allergen. Instead of triggering a harmful allergic reaction, the body learns to tolerate the allergen. This is achieved through repeated exposure to increasing doses of the allergen, leading to a shift in the immune response. Imagine it like slowly introducing a small, fearful puppy to a cat – over time, with careful management, the puppy’s fear diminishes, and they eventually coexist peacefully.

The mechanism involves several key processes: a reduction in allergen-specific IgE antibodies (the antibodies responsible for triggering allergic reactions), an increase in allergen-specific IgG antibodies (which block IgE activity), and a shift in the T-helper cell balance towards a regulatory T cell response (suppressing the allergic response).

Both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) aim to achieve allergen-specific tolerance, but they differ in their route of administration. SCIT involves injections under the skin, typically administered weekly at an allergist’s office, while SLIT uses tablets or drops placed under the tongue.

SCIT generally provides a stronger and faster immune response, but it requires more frequent visits to the doctor’s office and carries a slightly higher risk of serious adverse reactions, although these are rare. SLIT is more convenient as it’s self-administered at home, but it may require longer treatment duration and its efficacy might be slightly lower depending on the allergen and individual.

Think of it as two different ways to achieve the same goal: SCIT is like a targeted injection, directly impacting the immune system, whereas SLIT is like a slow, steady absorption through the mucous membranes.

Contraindications for AIT are situations where the treatment poses a significant risk to the patient. These include:

• Severe asthma poorly controlled despite medication.
• Recent history of serious allergic reactions (anaphylaxis).
• Use of beta-blockers (certain heart medications that can worsen allergic reactions).
• Uncontrolled autoimmune or immunodeficiency disorders.
• Pregnancy.
• Severe mental health conditions that would prevent adherence to treatment.

It’s crucial to perform a thorough evaluation to identify contraindications and avoid potential complications.

Managing adverse reactions during AIT is critical. Mild reactions, such as itching or mild swelling at the injection site (SCIT) or mild oral irritation (SLIT), are usually managed with antihistamines. More severe reactions, like widespread hives, angioedema (swelling of the face, lips, or throat), or respiratory distress, require immediate action.

This involves:

• Immediate discontinuation of the treatment.
• Administration of epinephrine (adrenaline) if necessary.
• Monitoring vital signs (heart rate, blood pressure, breathing).
• Observing the patient for a significant period after the reaction.
• Emergency medical services should be contacted if necessary.

Patients undergoing AIT should always carry an emergency kit containing epinephrine and antihistamines and be educated on how to recognize and respond to adverse reactions.

AIT can treat a wide range of allergens, including:

• Pollens (grass, tree, weed): responsible for seasonal allergic rhinitis (hay fever).
• Dust mites: common indoor allergens contributing to perennial rhinitis and asthma.
• Animal danders (cats, dogs): causing allergic reactions in susceptible individuals.
• Insect venoms (bees, wasps): preventing severe allergic reactions after stings.
• Foods (in limited cases): though less common than for respiratory allergens.

The specific allergen(s) targeted are determined through a detailed allergy evaluation.

The long-term benefits of AIT are significant and can lead to sustained relief from allergic symptoms. This includes a reduction in the severity and frequency of allergic symptoms, decreased reliance on medication, and improved quality of life.

In some cases, the benefits can last for years or even decades after treatment is completed. This long-term control makes AIT a valuable therapeutic option compared to solely managing symptoms with medication.

Assessing a patient’s suitability for AIT involves a comprehensive evaluation that considers various factors. This starts with a thorough medical history and physical examination, followed by allergy testing (skin prick tests and/or blood tests) to identify specific allergens and the severity of the reaction.

The assessment also looks at:

• Severity of allergic symptoms: AIT is typically more effective for moderate to severe allergies.
• Control of underlying medical conditions: well-controlled asthma is crucial.
• Patient motivation and adherence: AIT requires commitment to the treatment schedule.
• Understanding and management of potential risks: patients need to be fully informed about the treatment and the management of adverse reactions.

Only after a comprehensive evaluation can a doctor determine if a patient is a suitable candidate for AIT.

Allergy skin testing is a crucial diagnostic tool in allergy immunology. It involves introducing small amounts of suspected allergens into the skin, typically through a prick or intradermal injection. The prick test involves pricking the skin with a lancet containing the allergen, while the intradermal test involves injecting a small amount of diluted allergen just beneath the skin’s surface.

Interpretation: A positive reaction is indicated by the appearance of a wheal (a raised, itchy bump) and flare (redness surrounding the wheal) at the test site within 15-20 minutes. The size of the wheal and flare is compared to a negative control and is graded according to a standardized scale. A larger wheal and flare indicates a more significant allergic reaction. For example, a patient might show a large reaction to cat dander, confirming a cat allergy, while showing only a tiny reaction or no reaction to pollen. This allows us to identify the specific allergens triggering the patient’s symptoms. A negative result means there’s no immediate hypersensitivity reaction to the tested allergen.

It’s important to note that skin testing can sometimes give false positive or false negative results. Factors like skin inflammation or medication use can influence the results. Therefore, the interpretation should always be done in the context of the patient’s medical history and clinical presentation.

Immunotherapy, while highly effective for many patients, can have side effects. These range from mild to severe, and their frequency and severity vary depending on the allergen, the dose, the route of administration (subcutaneous or sublingual), and the patient’s individual response.

• Local reactions: These are the most common and typically mild, including itching, swelling, and redness at the injection site (subcutaneous immunotherapy). For sublingual immunotherapy, mouth irritation or slight swelling can occur.
• Systemic reactions: These are less frequent but more serious. They can include generalized itching, hives, difficulty breathing, lightheadedness, or even anaphylaxis. Anaphylaxis is a rare but life-threatening emergency requiring immediate medical attention.
• Other side effects: Fatigue, flu-like symptoms, and occasionally gastrointestinal upset are also possible.

It’s critical that patients are carefully monitored for side effects and educated about recognizing and responding to potential reactions. The risk of serious side effects is mitigated through careful dose escalation and proper patient education.

Monitoring a patient’s response to immunotherapy involves a multifaceted approach, combining symptom tracking and objective measures.

• Symptom Diary: Patients keep a record of their allergy symptoms (e.g., sneezing, runny nose, asthma attacks) to track improvement over time. This provides valuable subjective data.
• Skin Prick Testing: Periodic skin testing measures the changes in the allergic response to the allergen. A reduction in wheal size indicates a successful desensitization effect.
• Specific IgE levels: Blood tests can measure the levels of allergen-specific IgE antibodies. Decreases in these levels indicate a decline in allergic sensitization.
• Peak Expiratory Flow Rate (PEFR): For asthma patients, PEFR monitoring helps assess respiratory function and improvement in lung capacity.
• Quality of Life Questionnaires: These tools assess the impact of allergies on daily life, capturing the improvement in a patient’s overall wellbeing.

Regular follow-up appointments with the allergist allow for a comprehensive assessment of the patient’s progress and adjustment of the immunotherapy regimen as needed. The frequency of monitoring varies based on the patient’s response and the type of immunotherapy used.

Immunoglobulin E (IgE) is a type of antibody that plays a central role in allergic reactions. It’s produced by plasma cells in response to exposure to allergens. When an allergen binds to IgE antibodies already attached to the surface of mast cells and basophils, it triggers a cascade of events leading to the release of inflammatory mediators (histamine, leukotrienes, etc.).

This release causes the symptoms characteristic of an allergic reaction, such as itching, swelling, and inflammation. Individuals with allergies have higher levels of allergen-specific IgE antibodies compared to non-allergic individuals. The measurement of specific IgE levels is a valuable tool in diagnosing allergic conditions.

For example, a person allergic to peanuts will have high levels of peanut-specific IgE. When they consume peanuts, the peanut proteins bind to the pre-existing peanut-specific IgE on their mast cells and basophils, triggering the release of mediators and resulting in an allergic reaction.

Hypersensitivity reactions are classified into four types based on their underlying mechanisms. Understanding these types is essential for appropriate diagnosis and management of allergic conditions.

• Type I (Immediate Hypersensitivity): This is the classic allergic reaction, mediated by IgE antibodies. It involves mast cell and basophil degranulation, leading to the rapid release of inflammatory mediators. Examples include allergic rhinitis, asthma, and anaphylaxis.
• Type II (Antibody-mediated Hypersensitivity): Involves IgG or IgM antibodies binding to antigens on cell surfaces, leading to cell destruction or dysfunction. An example is autoimmune hemolytic anemia.
• Type III (Immune Complex-mediated Hypersensitivity): Involves the formation of antigen-antibody complexes that deposit in tissues, activating the complement system and causing inflammation. Examples include serum sickness and certain types of glomerulonephritis.
• Type IV (Delayed-type Hypersensitivity): This is a cell-mediated response, involving T lymphocytes, and is not antibody-mediated. It typically takes 24-72 hours to develop. Examples include contact dermatitis (e.g., poison ivy) and tuberculin skin test reactions.

Differentiating between these types is crucial, as they require different diagnostic and therapeutic approaches.

Mast cells and basophils are key effector cells in allergic reactions. Both are granulocytes that contain granules filled with various inflammatory mediators.

Mast cells are tissue-resident cells found throughout the body, particularly in mucosal tissues. They express high-affinity receptors for IgE (FcεRI). When an allergen binds to IgE bound to FcεRI on mast cells, it triggers degranulation, releasing histamine, heparin, tryptase, and other mediators that cause vasodilation, increased vascular permeability, smooth muscle contraction, and mucus secretion – all hallmarks of allergic reactions.

Basophils are circulating granulocytes that also express FcεRI and play a similar role to mast cells in allergic reactions. Upon activation by allergen-bound IgE, they also release inflammatory mediators, contributing to the overall allergic response. While they share many similarities, mast cells tend to play a more prominent role in the initial phase of allergic responses, whereas basophils might contribute to later stages or to ongoing inflammation.

For example, in hay fever, both mast cells in the nasal mucosa and circulating basophils contribute to the symptoms of sneezing, rhinorrhea, and nasal congestion.

Immunological tolerance refers to the state of unresponsiveness of the immune system to a specific antigen. This prevents the immune system from attacking the body’s own tissues (self-tolerance) or harmless environmental antigens. Several types of immunological tolerance exist:

• Central tolerance: This occurs during the development of lymphocytes in the thymus (T cells) and bone marrow (B cells). Self-reactive lymphocytes are either deleted or rendered anergic (non-responsive).
• Peripheral tolerance: This occurs in the periphery after lymphocytes have matured. Mechanisms include anergy (functional inactivation), suppression by regulatory T cells (Tregs), and deletion of self-reactive lymphocytes.
• Oral tolerance: This involves the induction of tolerance through oral administration of antigens. It’s thought to involve the generation of Tregs in the gut-associated lymphoid tissue.
• Bystander suppression: In this mechanism, exposure to one antigen can suppress the immune response to a different antigen.

Understanding the mechanisms of immunological tolerance is crucial for the development of new therapeutic strategies for autoimmune diseases and allergies. Immunotherapy, for instance, aims to induce tolerance to allergens by gradually exposing the immune system to increasing amounts of the allergen, thus modifying the immune response.

Immunotherapy for allergies, also known as allergen-specific immunotherapy (AIT), works by gradually introducing increasing amounts of the allergen a patient is sensitive to. This process aims to shift the immune response from a harmful, allergic reaction (Th2-dominated) to a more tolerant state (Th1 or Treg-dominated). It doesn’t completely eliminate the allergy, but it significantly reduces the severity of reactions.

The mechanism is multifaceted. It involves several key processes:

• Induction of regulatory T cells (Tregs): Tregs are a type of immune cell that suppresses the activity of other immune cells, thereby preventing an exaggerated allergic response. AIT promotes the expansion and activity of Tregs.
• Shift in cytokine production: AIT influences the balance of cytokines—messenger molecules that regulate immune responses. It reduces the production of pro-inflammatory cytokines like IL-4, IL-5, and IL-13 (associated with allergic responses) and promotes the production of anti-inflammatory cytokines like IL-10 and TGF-β.
• Anergy: Repeated exposure to the allergen can lead to a state of anergy, where the allergen-specific immune cells become unresponsive.
• Antibody isotype switching: AIT can promote a shift from IgE (the antibody involved in allergic reactions) to IgG antibodies, which are less likely to trigger allergic responses.

Think of it like slowly desensitizing the immune system to the allergen. Instead of a loud alarm bell, the body learns to treat the allergen as a minor annoyance.

Cytokines play a pivotal role in allergic inflammation. They are small proteins that act as messengers between immune cells, orchestrating the inflammatory response. In allergies, the imbalance of cytokine production is crucial.

• Pro-inflammatory cytokines: These cytokines drive the allergic response. Key players include IL-4, IL-5, and IL-13, produced by Th2 helper T cells. IL-4 promotes IgE production, IL-5 stimulates eosinophil production and activation (a type of white blood cell involved in allergic reactions), and IL-13 contributes to mucus production and airway hyperresponsiveness.
• Anti-inflammatory cytokines: These cytokines help to regulate and suppress the inflammatory response. Key examples include IL-10 and TGF-β, which can inhibit the production of pro-inflammatory cytokines and promote the differentiation of regulatory T cells (Tregs).

For example, in allergic rhinitis (hay fever), pollen triggers the release of IL-4, IL-5, and IL-13, leading to inflammation, sneezing, and nasal congestion. In asthma, similar cytokines contribute to bronchoconstriction and airway inflammation.

Understanding the cytokine profile in a specific allergic condition is essential for guiding treatment strategies. Targeting specific cytokines through biologics is a promising area of research.

Antihistamines and corticosteroids are cornerstones of managing allergic reactions, but they work through different mechanisms.

• Antihistamines: These medications block the action of histamine, a chemical mediator released by mast cells during allergic reactions. Histamine is responsible for many of the symptoms of allergies, such as itching, sneezing, runny nose, and swelling. Antihistamines effectively alleviate these symptoms, but they do not address the underlying cause of the allergy.
• Corticosteroids: These are potent anti-inflammatory drugs that reduce inflammation by suppressing the activity of various inflammatory cells and mediators. They are particularly effective in reducing airway inflammation in asthma and controlling severe allergic reactions. They are often used in conjunction with antihistamines for a more comprehensive approach.

Imagine a fire: antihistamines are like putting out small sparks, while corticosteroids are like using a fire extinguisher to tackle the larger blaze of inflammation.

The choice between antihistamines and corticosteroids depends on the severity and type of allergic reaction. Mild allergic rhinitis might be effectively managed with antihistamines alone, while severe asthma may require corticosteroids along with other medications.

Allergy immunotherapy has seen significant advancements in recent years, moving beyond traditional subcutaneous injections.

• Sublingual immunotherapy (SLIT): This involves administering allergen extracts under the tongue, offering a convenient and less invasive alternative to injections. It’s generally well-tolerated and effective for many allergic conditions.
• Specific immunotherapy with modified allergens: Scientists are developing modified allergens that are less allergenic but still capable of inducing immunological tolerance. This includes using hypoallergenic derivatives or fragments of allergens.
• Personalized immunotherapy: This approach tailors the immunotherapy regimen to the individual’s specific allergic profile, focusing on the most relevant allergens and optimizing the treatment strategy. This potentially improves efficacy and minimizes side effects.
• Novel delivery systems: Research is ongoing to explore new delivery systems for immunotherapy, including patches and inhalers, further enhancing patient convenience and compliance.
• Biologics targeting specific immune pathways: Advances in understanding the immune system have led to the development of biologics that target specific immune pathways implicated in allergies, offering an alternative or complementary approach to traditional immunotherapy.

These advancements aim to make allergy immunotherapy more accessible, effective, and tolerable for patients.

Approaching a patient with a complex allergic profile requires a systematic and multidisciplinary approach.

1. Thorough history and physical examination: A detailed history of allergies, including triggers, symptoms, and severity, is crucial. This should be supplemented with a comprehensive physical exam.
2. Allergy testing: Skin prick testing and/or blood tests (such as ImmunoCAP) are used to identify specific allergens causing the reactions.
3. Differential diagnosis: It’s essential to rule out other conditions that might mimic allergic reactions. For instance, some symptoms might be attributable to environmental irritants or other underlying medical issues.
4. Treatment plan: A personalized treatment plan should incorporate strategies to reduce exposure to allergens (avoidance), symptom management using medications (like antihistamines or corticosteroids), and potentially allergy immunotherapy, targeting the most relevant allergens.
5. Regular follow-up: Close monitoring of symptoms and medication effectiveness is essential. The treatment plan might need adjustment based on the patient’s response.

Collaboration with other specialists, such as pulmonologists (for asthma), dermatologists (for eczema), or gastroenterologists (for food allergies), might be necessary depending on the complexity of the patient’s profile.

Counseling a patient about immunotherapy involves a transparent discussion of both risks and benefits. I would start by explaining that immunotherapy is not a cure but a long-term treatment aimed at reducing the severity and frequency of allergic reactions.

Benefits: I’d highlight the potential for long-term relief, reduced reliance on medications, and improvement in quality of life. I would tailor this to the specific allergic condition and patient’s current experience. For example, a patient with severe seasonal allergies might anticipate significantly fewer allergy days and a decreased need for daily medications.

Risks: I would explain potential side effects such as local reactions at the injection site (for subcutaneous immunotherapy), systemic reactions (though rare and generally manageable), and the commitment required for the treatment course (typically lasting several years). I would discuss potential interactions with other medications and any precautions they should take.

I would emphasize shared decision-making, empowering the patient to make informed choices based on their understanding of the risks and benefits. I’d use clear language, avoiding jargon, and make sure the patient feels comfortable asking questions. The goal is to provide a balanced perspective that allows the patient to make a well-informed decision about whether immunotherapy is right for them.

My experience administering immunotherapy injections involves a rigorous adherence to safety protocols. I start with a thorough assessment of the patient’s medical history and current allergy symptoms to gauge their suitability for immunotherapy and identify any contraindications.

Before administering the injection, I always check the patient’s identification and allergen extract details, ensuring the right patient receives the right allergen at the right concentration. I follow a gradual up-dosing schedule, carefully observing for any signs of allergic reactions—this might range from mild local reactions (redness, swelling) to more severe systemic reactions (hives, shortness of breath). I have a detailed protocol for managing allergic reactions in place, including access to emergency medications (epinephrine) and trained personnel.

After each injection, I monitor the patient for at least 30 minutes, and the patient is instructed to contact us if any reactions develop later. Detailed documentation of the injection, dose, and any observed reactions is crucial. I regularly review the patient’s progress, adjusting the treatment strategy as needed, and always keeping them informed of the procedure and any changes to the plan. Patient education is paramount to ensure they are comfortable and well-informed throughout the process.

Anaphylaxis is a life-threatening allergic reaction requiring immediate action. It’s characterized by symptoms like difficulty breathing, swelling of the throat or tongue, a rapid drop in blood pressure, and hives.

My approach involves a three-pronged strategy:

• Immediate Action: Administering epinephrine (adrenaline) via an auto-injector (like an EpiPen) is paramount. This medication counteracts the effects of histamine, a key chemical mediator in allergic reactions. I instruct patients and their families on proper auto-injector use. Simultaneously, I would call emergency medical services (EMS).
• Supportive Care: Once EMS arrives, they’ll provide advanced support including oxygen, intravenous fluids, and monitoring vital signs. In the hospital, further treatment may involve antihistamines, corticosteroids, and potentially airway management.
• Long-Term Management: After anaphylaxis, a thorough review of the patient’s allergy history and triggers is essential. This includes identifying potential allergens, ensuring the patient has readily available epinephrine, and developing an action plan for future exposures. We’d also discuss potential allergy immunotherapy to help prevent future episodes.

For example, a patient who experienced anaphylaxis after a bee sting would receive immediate epinephrine, followed by observation in the hospital. We’d then discuss venom immunotherapy to desensitize them to bee stings.

Diagnosing food allergies involves a careful history taking, physical examination and specific testing. We look for a clear temporal relationship between food ingestion and symptom onset.

My approach combines several methods:

• Detailed History: A comprehensive dietary history is crucial, detailing specific foods eaten, the timing of symptoms, and the symptom severity. We explore potential cross-reactivity among foods.
• Skin Prick Testing: This is a quick and relatively inexpensive test that involves pricking the skin with diluted allergen extracts. A positive reaction (wheal and flare) indicates sensitization.
• Specific IgE blood testing: Measures the amount of IgE antibodies specific to certain allergens. It helps to confirm skin prick test results, particularly if skin tests are inconclusive or contraindicated.
• Oral Food Challenge (OFC): This is a controlled test involving the gradual ingestion of the suspected allergen under medical supervision. It’s the gold standard for confirming a food allergy diagnosis. The OFC must only be done when appropriate by a trained professional in a closely monitored setting.

Imagine a child with recurrent hives after eating peanuts. We’d start with a detailed dietary history, followed by skin prick and IgE testing for peanut allergens. A positive result would be confirmed (or refuted) with a carefully performed OFC.

Allergen immunotherapy, while highly effective for many, isn’t without challenges.

• Time Commitment: It requires multiple injections or sublingual administrations over a prolonged period, often several months or years, demanding patient compliance.
• Side Effects: Local injection site reactions (pain, swelling, redness) are common, while systemic reactions (such as hives or breathing difficulties) are less frequent but require close monitoring.
• Not All Allergies: It’s not equally effective for all allergies or all individuals. Some allergies, like food allergies in children, may not be ideal candidates for immunotherapy.
• Cost and Accessibility: Immunotherapy can be expensive, and access may be limited depending on insurance coverage and the availability of qualified allergists.

For example, a patient with seasonal allergies might experience some injection site reactions during immunotherapy. It’s crucial to discuss potential side effects and manage expectations.

Allergic rhinitis and non-allergic rhinitis both cause similar symptoms like nasal congestion, sneezing, and runny nose, but their underlying causes differ. Allergic rhinitis is an IgE-mediated response to specific allergens, while non-allergic rhinitis stems from other triggers.

Key Differences:

• Underlying Cause: Allergic rhinitis is triggered by specific allergens (pollen, dust mites, pet dander), whereas non-allergic rhinitis is caused by irritants (smoke, perfumes, temperature changes), infections (viral colds), or hormonal changes.
• Diagnostic Testing: Allergic rhinitis is diagnosed through skin prick tests, IgE blood tests, and a detailed history of allergen exposure. Non-allergic rhinitis is diagnosed largely through the exclusion of allergic triggers.
• Symptom Profile: While symptoms overlap, allergic rhinitis often involves itchy eyes and nose, whereas non-allergic rhinitis may not.

A patient presenting with nasal symptoms might have allergic rhinitis if their symptoms are seasonally linked and improve when allergens are avoided. In contrast, a patient with constant nasal symptoms triggered by perfumes or cold air may have non-allergic rhinitis.

Laboratory tests play a crucial role in confirming or refuting an allergy diagnosis. They provide objective data to support clinical findings.

Common Tests:

• Skin Prick Test: This measures the immediate hypersensitivity reaction to allergens.
• Specific IgE Antibody Testing (RAST): Detects IgE antibodies to specific allergens in the blood.
• Total IgE Level: Provides a general indication of immune system activation, though it’s not specific to any allergen.
• Other Tests: Depending on the clinical situation, other tests may be used, such as nasal cytology, to examine the cells present in nasal secretions.

For example, a negative skin prick test but a positive specific IgE for peanut allergen may indicate a need for a controlled oral food challenge to clarify the diagnosis.

Patient education is paramount for successful immunotherapy. I use a multi-pronged approach:

• Detailed Explanation: I clearly explain the purpose of immunotherapy, the treatment schedule, and potential side effects in a language the patient can easily understand.
• Realistic Expectations: I manage patient expectations by highlighting that immunotherapy takes time and may not completely eliminate allergy symptoms, but it usually reduces their severity and frequency.
• Symptom Management: I teach patients how to manage side effects like injection site reactions and potential systemic reactions.
• Self-Care: I empower patients by teaching them to recognize early signs of allergic reactions and how to use their medication.
• Follow-up: Regular follow-up appointments are crucial for monitoring progress, adjusting treatment, and addressing any concerns.

For example, I would show a patient a diagram illustrating the gradual increase in allergen dose during subcutaneous immunotherapy and discuss the importance of following the injection schedule.

My experience encompasses both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT).

SCIT: I have extensive experience administering SCIT for various allergies, including seasonal allergies (pollen, grass), insect venom allergies (bee, wasp), and some drug allergies. This involves a gradual increase in allergen dose administered via injection. Precise dosing and monitoring for reactions are essential.

SLIT: SLIT involves placing allergen extracts under the tongue. This approach is often preferred for some allergies due to its convenience and reduced risk of systemic reactions compared to SCIT. I carefully select appropriate candidates for SLIT, considering factors such as patient compliance and allergy severity.

For example, a patient with severe seasonal allergies might be a good candidate for SCIT, while a patient with mild pollen allergies might benefit from SLIT. The choice of protocol is always tailored to the individual needs and risk profile.