Asthma is a chronic disease involving the bronchial tubes which move air in and out of the lungs. There are many forms of asthma. Allergic asthma is triggered by the presence of an allergen. An allergic response happens when a substance is introduced and antibodies mistake the harmless substance as a threat. To protect the body the antibodies begin to attack. Chemicals released by the immune system lead to traditional allergy symptoms such as a runny nose, nasal congestion, skin reactions, or itchy eyes. In some individuals this allergic response can also manifest in the lungs and airways which causes asthma symptoms.
Symptoms
People suffering from allergic asthma can go months, or more, between asthma attacks depending on their exposure to allergens. There are symptoms common to allergic asthma regardless of the type of allergen causing the attack, these include:
- Chest pressure
- Chest tightness
- Cough, usually occurring at night
- Shortness of breath
- Shortness of breath
- Wheezing
Causes
Any allergen can trigger an asthma attack in those sensitive to the allergen and susceptible to asthma. However, the most common allergens leading to asthma are:
- Animal dander
- Animal hair
- Chemicals in food
- Chemicals in the air
- Dust mites
- Fumes and smoke from burning gas or wood
- Molds
- Pollens
- Pollution
- Tobacco smoke
Tests
There are two types of tests that need to be performed in order to determine if a patient has allergic asthma. The doctor will need to test for allergies and have the patient complete a pulmonary function test. Prior to any allergy tests patients are typically asked to abstain from any allergy medications which could mask an allergic response.
• Allergy Tests – There are several components to allergy testing. First, the doctor will perform a physical exam and look for signs of an allergic reaction. Then they may perform a skin test or have blood drawn for testing. There are several forms of allergy skin tests including:
- Intradermal test – The skin is cleaned and dried and then a small amount of an allergen is injected into the skin. This is usually done on the patient’s back but may also be done on the arm.
- Patch test – An allergen is placed on a patch which is then applied to the skin.
- Scratch test – The skin of the back or arm is cleaned and dried. Marks are placed on the skin with a marker to identify where each allergen is being tested. A drop of the allergen is then placed on each corresponding mark and the skin is pricked to allow the allergen to penetrate the epidermis. The device used is similar to those used for testing the blood of diabetics and is not painful.
• Pulmonary Lung Function Test – The patient inhales deeply and the forcefully exhales into a tube connected to a spirometer. The machine records the volume of air exhaled as well as the rate of exhalation. If key measurements are below normal this can be an indication of asthma. After the initial test the physician may have the patient inhale an asthma medication and repeat the test to measure improvements.
Treatments
Treatments for allergy induced asthma have to focus on the two components of the condition; allergies and asthma. In order to prevent, or at least limit, asthma attacks the allergy symptoms must also be controlled. The most important step individuals can take is to limit their contact with known allergens. Medical options include:
• Allergy Medications – These may include nasal sprays or oral medications that work as antihistamines and decongestants. There are both over the counter and prescription options available.
• Allergy Shots – Immunotherapy is an option for those who cannot avoid their triggers. The patient receives a series of injections containing small doses of the allergen. Typically injections occur once a week for several months and then once a month for up to five years. Desensitization takes time and is not a quick solution and may not be viable for all patients.
• Leukotriene Modifier – Montelukast helps reduce the symptoms of both allergies and asthma. The medication is taken daily to control the immune system response produced during an allergic reaction. These medications have been linked to psychological reactions such as suicidal thoughts.
• Omalizumab – This medication helps reduce the immune system reaction that can cause asthma and allergy symptoms. It is injected every two to four weeks. Some patients have experienced a severe anaphylactic reaction to the medication.
• Rescue Medications – Rescue inhalers provide quick-acting medications directly into the lungs in a fine mist. These types of medications relax airway muscles and allow the lungs to open. This is used to ease symptoms or stop an active asthma attack because they begin working within minutes and may provide relief for up to six hours.
Allergic asthma is a chronic condition. It is typically treated by reducing the impact of the allergens the patient is exposed to daily and by treating asthma symptoms as they occur. It is important for patients to follow the plan of care provided by their physician carefully. Regular checkup will ensure medications are properly adjusted to allow for maximum efficacy.