Rhinitis: Differentiating between Allergic and Non-Allergic Rhinitis- Dr Meghana Potluri

Allergic rhinitis is an allergic reaction that occurs when your immune system overreacts to allergens in the air, such as pollen, dust mites, mould, or pet dander. Symptoms include sneezing, a runny or stuffy nose, itchy or watery eyes, and itching in the throat or ears. It can be seasonal (often triggered by pollen from trees, grasses, or weeds) or perennial (occurring year-round due to indoor allergens).

Non-allergic rhinitis is a condition that causes similar symptoms to allergic rhinitis—such as a runny or stuffy nose, sneezing, and post-nasal drip—but isn't triggered by allergens. Instead, it may result from a variety of other factors.

Types and Causes of Non-Allergic Rhinitis

1. Vasomotor Rhinitis: Often triggered by changes in temperature, humidity, strong odours, or smoke. It involves a dysfunction in the regulation of nasal blood flow.

2. Infectious Rhinitis: Caused by infections, such as the common cold or sinusitis. This type typically resolves as the infection clears up.

3. Medication-Induced Rhinitis:

• Overuse of Nasal Decongestant Sprays: Prolonged use can lead to rebound congestion.
• Certain Medications: Such as blood pressure drugs (e.g., beta-blockers) or oral contraceptives.

4. Hormonal Rhinitis: Changes in hormones, such as during pregnancy, menstruation, or thyroid dysfunction, can cause nasal symptoms.

5. Occupational Rhinitis: Exposure to irritants or allergens in the workplace.

6. Idiopathic Rhinitis: Sometimes, no specific cause is identified, and the condition is termed idiopathic.

Diagnostic Approaches

1. Medical History and Symptom Assessment:

• Detailed questioning about symptoms, their onset, duration, and any potential triggers.

• Skin Prick Tests or Blood Tests: To identify specific allergens if allergic rhinitis is suspected.

3. Nasal Examination:

• Endoscopy or Rhinoscopy: To check for structural abnormalities or signs of inflammation.

4. Trial Treatment:

• Antihistamines: If symptoms improve with antihistamines, allergic rhinitis is more likely.
• Nasal Corticosteroids and Saline Sprays: Used to see if symptoms improve, which can help in diagnosing non-allergic rhinitis.

If you’re unsure or if symptoms are persistent, consulting a healthcare provider can help determine the exact cause and appropriate treatment plan.

Management and Treatment

1. Avoidance of Triggers: Identifying and avoiding environmental or irritant triggers can help manage symptoms. For example, if certain odors or smoke trigger your symptoms, try to avoid them.

2. Medications:

• Nasal Corticosteroids: Effective for reducing inflammation and nasal congestion.
• Antihistamines: Can be helpful if there is an overlap with allergic symptoms.
• Saline Nasal Sprays: Help to moisten nasal passages and reduce congestion.

3. Proper Use of Nasal Sprays: If using nasal decongestants, follow instructions carefully to avoid rebound congestion.

4. Addressing Underlying Conditions: If hormonal or medication-related, treating the underlying issue can alleviate rhinitis symptoms.

Differentiating between allergic and non-allergic rhinitis involves assessing symptoms, triggers, and response to treatment. Here’s a breakdown of key differences and diagnostic approaches:

Symptoms

1. Allergic Rhinitis:

• Onset: Often occurs seasonally (e.g., spring or fall) or in response to specific allergens.
• Common Symptoms: Sneezing, itchy or watery eyes, itchy throat or ears, and a clear, watery nasal discharge.
• Other Indicators: Often accompanied by other allergic symptoms such as eczema or asthma.

• Onset: Can occur year-round or in response to irritants or other non-allergic triggers.
• Common Symptoms: Nasal congestion, runny nose, post-nasal drip, but usually lacks the itching and watery eyes associated with allergies.
• Triggers: Includes changes in weather, strong odours, smoke, medications, or hormonal changes.

Triggers

1. Allergic Rhinitis:

• Common Triggers: Pollen, dust mites, mould, pet dander, or certain foods.
• Identification: Symptoms often correlate with exposure to specific allergens and improve when away from the trigger.

• Common Triggers: Changes in weather, strong smells, smoke, or hormonal changes.
• Identification: Symptoms may be more consistent regardless of exposure to specific allergens.

Response to Treatment

• Effective Treatments: Antihistamines, nasal corticosteroids, and avoidance of allergens.
• Improvement: Symptoms typically improve with these treatments and when avoiding allergens

• Effective Treatments: Nasal corticosteroids, saline nasal sprays, and avoiding known irritants. Antihistamines may not be as effective unless there’s a component of allergic response.
• Improvement: Symptoms improve with appropriate treatment and management of triggers but may not respond well to antihistamines alone.