Allergies can significantly impact everyday life, causing discomfort and, in severe cases, life-threatening reactions. Identifying specific allergens is critical to effective treatment. Radioallergosorbent testing (RAST) is a reliable blood test designed to detect sensitivity to particular allergens by measuring the presence of immunoglobulin E (IgE) antibodies in the blood.
What Does a Radioallergosorbent Test (RAST) Detect?
The RAST is primarily used to identify sensitivities to various allergens, including:
- Food Allergens: These include items like peanuts, eggs, shellfish, and dairy that can trigger allergic reactions such as hives, stomach pain, or even anaphylaxis in sensitive individuals.
- Environmental Allergens: Substances like pollen, mold, dust mites, and pet dander are shared triggers of sneezing, itchy eyes, and asthma symptoms.
- Insect Venoms: Venoms from stings by bees, wasps, and other insects can cause severe allergic responses.
- Latex: Found in products like gloves, balloons, and medical supplies, latex can cause skin rashes or breathing issues in allergic people.
Understanding Complete Blood Count (CBC) Normal Range
While the RAST focuses on detecting specific IgE antibodies related to allergies, it’s often performed alongside a Complete Blood Count (CBC) to provide a comprehensive overview of an individual’s health. The normal ranges for CBC components are:
| Blood Component | Normal Range |
| Red Blood Cells (RBCs) | Men: 4.7–6.1 million/µL
Women: 4.2–5.4 million/µL |
| White Blood Cells (WBCs) | 4,500–11,000 cells/µL |
| Hemoglobin | Men: 13.8–17.2 g/dL
Women: 12.1–15.1 g/dL |
| Platelets | 150,000–450,000 platelets/µL |
Radioallergosorbent Test (RAST) Price
At Max Hospital, we offer a full range of RAST services at a competitive price ₹, ensuring affordability without compromising quality. Our state-of-the-art laboratory facilities and experienced medical professionals provide accurate and timely results for domestic and international patients.
Diseases Detected by the Radioallergosorbent Test (RAST)
The RAST is instrumental in diagnosing various allergic conditions, including:
- Allergic Rhinitis: Commonly known as hay fever, branded by sneezing, nasal congestion, and itchy eyes.
- Asthma: Allergens trigger airway inflammation, leading to breathing difficulties.
- Eczema (Atopic Dermatitis): Chronic inflammation resulting in itchy and red skin.
- Anaphylaxis: A severe, potentially life-threatening allergic reaction requiring immediate medical attention.
Identifying specific allergens through RAST enables healthcare providers to develop personalized management plans, potentially reducing the severity and frequency of allergic reactions.
Radioallergosorbent Test (RAST) Results Interpretation
RAST results are typically reported on a scale from 0 to 6, indicating the level of specific IgE antibodies present:
- Grade 0: <0.35 kU/L – Negative (No significant allergen-specific IgE detected)
- Grade 1:35–0.70 kU/L – Low level
- Grade 2:70–3.50 kU/L – Moderate level
- Grade 3:50–17.50 kU/L – High level
- Grade 4:50–50.00 kU/L – Very high level
- Grade 5:00–100.00 kU/L – Ultra high level
- Grade 6: >100.00 kU/L – Extremely high level
Higher scores indicate greater sensitivity to the specific allergen tested. Discussing these results with a healthcare professional to understand their meaning entirely is essential.
Composition and Ingredients of the Radioallergosorbent Test (RAST)
The RAST involves:
Allergen extracts: Specific proteins of potential allergens that are used to detect IgE antibodies.
Patient serum: The liquid component of blood in which IgE antibodies are measured.
Radiolabeled IgE antibodies: These are used to detect the presence of allergen-specific IgE in the patient’s serum.
Each component plays a crucial role in precisely identifying allergen sensitivities.
Uses of the Radioallergosorbent Test (RAST)
The RAST is utilized for:
- Diagnosis of allergic conditions: identification of specific allergens responsible for allergic reactions.
- Monitoring allergy treatment: evaluating the effectiveness of allergen avoidance strategies or immunotherapy.
- Preoperative assessment: evaluation of possible allergic reactions to anesthesia or surgical material.
- Assessment of occupational hygiene: determination of sensitivity to allergens in the workplace.
Individuals can make informed results about their environment and lifestyle by understanding allergen sensitivities.
Side Effects and Risks of the Radioallergosorbent Test (RAST)
The RAST is a simple blood test with minimal risks. Potential side effects include:
- Mild Pain or Bruising: At the site anywhere the blood sample is taken.
- Dizziness or Lightheadedness: Rare and typically short-lived.
- Infection: Extremely rare if proper sterile techniques are used.
These side effects are generally provisional and resolve without intervention.
Book Your RAST Test at Max Hospital Today!
Don’t let undiagnosed allergies affect your health and quality of life. Max Hospital offers comprehensive Radioallergosorbent Testing (RAST) using cutting-edge technology and expert lab testing. Get accurate results, affordable prices, and personalized attention — all under one trusted brand.
Book your RAST test now at Max Hospital and take the first step toward a safer, allergy-free life!
Call us or book online to schedule an appointment and receive timely reports quickly.
FAQs
Is the Radioallergosorbent Test done before surgery?
Yes, in some instances, especially if there’s a history of allergic reactions to anesthesia or surgical materials, a RAST may be conducted to identify potential allergens.
How long does it take to receive RAST results?
Results are typically available within a few days, depending on the laboratory’s processing time.
Is fasting required before undergoing a RAST?
No, fasting is not necessary before a RAST. Patients can eat and drink before the test.
Can medications affect RAST results?
Unlike skin prick tests, antihistamines and other medications do not significantly interfere with RAST results, making them a preferred option for people undergoing this treatment.