There is no definitive treatment for allergy that works to completely and permanently cure you of hypersensitivity to any allergen. An allergen is a substance that causes your allergic reaction or hypersensitivity reaction.
Having said that, then what does the treatment do?
Allergy treatments aim to get rid of your allergy symptoms and give you relief. In other words, the allergic reactions that you suffer from, because of exposure to an allergic substance, heal or disappear with treatment. However, they will reappear when you get exposed to the allergen again.
To understand how allergy medicines work, you should first understand how allergic reactions occur. It is explained in what causes allergy. But we will have a quick review here.
How do you get an allergic reaction?
Our body has an immune system, which protects the body from any harmful substance that comes in contact with it. It could be by touch (as with poison ivy) or through food (like after eating prawns) and drink or through the air that we breathe in (like pollen), or it could be due to a drug injected into the body (penicillin). Such a substance is called an antigen. In the case of an allergic reaction, it is called an allergen.
Allergy is an abnormal and exaggerated response of our immune system to a substance that is otherwise safe. The immune system views this otherwise safe substance (called an allergen in the case of an allergic reaction) as a harmful substance and calls on its “forces” to attack it. The “forces” are mainly the white blood cells of which the mast cells play a fundamental role in regulating the immune system.
The immune system forms antibodies against the allergen. These are called the immunoglobins E cells (IgE, in short). The reaction between the allergen and the IgE antibodies results in the release of certain chemicals by the mast cells, which cause allergic reaction symptoms such as skin rash and hives.
Histamine is the main chemical responsible for allergy symptoms. It binds to the receptors in the blood vessels causing them to enlarge.
Histamine can also bind to other receptors. As explained above, histamine is released when there is an allergen and antibody reaction. It is the action of histamine on the receptors, which causes the allergic reaction. There are four types of receptors identified so far.
They are classified as H1, H2, H3, and H4. Each has its specific place in the body. They are found in the brain, the nervous system, the skin, the stomach, the intestines, and so forth.
The action of histamine upon the particular receptors depends on where the histamine is released in the body during the reaction. For example, a food allergy will release the histamine in the stomach and the intestines giving rise to symptoms of food allergy.
The allergy reaction is also associated with inflammation. As a matter of fact, inflammation is known to be the main pathophysiological characteristic of allergy. That is why steroids are justified in the use of allergy treatment due to their anti-inflammatory properties.
Allergy treatment guidelines
- Find the right doctor who is an allergist. An allergist is a doctor who specializes in the diagnosis and management of allergies.
- He will diagnose the cause of your allergy (the allergen) and instruct you to avoid it at all times.
- Taking medications, which are in essence allergy pills. They are mainly antihistamines. Besides the oral route, these drugs can also be given intramuscular (in the muscle) or intravenously (in the vein).
- Similarly, steroid oral tablets or injections may also be required to be given, depending on the severity of the allergy reaction and the presence of inflammation.
- Allergy eye drops are prescribed for red, itchy, and watery eyes caused by eye allergies triggered by dust, cigarette smoke, perfumes, pollen, diesel exhaust, etc.
- Allergen immunotherapy in the form of allergy shots or in the sublingual tablet form is used as a preventive treatment for allergic reactions to allergens such as grass pollens, house dust mites, and bee venom. It helps to reduce the frequency and severity of symptoms such as allergic rhinitis, bronchial asthma, and allergic conjunctivitis.
- Last but not least, your diet forms an important part of your allergy treatment.
These, in essence, form the guidelines to relieve your allergy misery and which may take a few days. Allergen immunotherapy also called allergy shots, however, is a long-term treatment.
Your allergist has diagnosed what has caused your allergy and he will tell you to avoid the allergen at all times. This is the primary step you have to take to make your anti-allergy therapy work.
Having registered that, we start with treatment as follows:
- Drugs to treat mild to moderate allergy
- Treatment of a severe allergic reaction (anaphylactic shock)
- Immunotherapy also called allergy shots to prevent or reduce the frequency of allergy attacks
1. Anti-allergy medication to treat mild to moderate allergy attacks
Drugs to treat skin allergies
For itchy allergic skin rash take oral OTC antihistamines and apply hydrocortisone 1% skin cream, which is a topical steroid available over the counter.
For hives, also called urticaria, your dermatologist will prescribe oral antihistamines and oral corticosteroids such as prednisolone. Steroids are given for as short a duration as required and this duration depends on the severity of the condition. When it is to be stopped, your doctor will stop it by slow tapering the dose to prevent a rebound of the condition.
Contact dermatitis is treated with topical steroids creams or ointments. Oral antihistamines are given to relieve the itching over the skin. If an extended area of the skin is involved, your doctor may prescribe oral steroids for their anti-inflammatory effect.
Eczema or atopic dermatitis is a chronic condition that requires the use of long-term treatment. The following treatment guidelines may be followed:
- Avoid soaps. Use emollients instead
- Use pure cotton clothes
- Do not scratch the affected area
- Oral antihistamines are given to fight the itching
- Steroid creams are used to treat moist or weeping areas of skin. Ointments are used to treat areas of the skin, which are dry or thickened. Lotions are reserved for the scalp.
- If necessary, strong topical steroids for a short period of three days may be necessary for a flare-up of the eczematous condition.
- Eczema can get infected. In such cases, your doctor may prescribe a short course of oral antibiotics and steroids along with a topical antibiotic-steroid combination.
Drugs to treat eye allergies
Allergy eye drops are liquid preparations for topical use to treat symptoms of eye allergy such as burning in the eyes, itching, a feeling of a foreign body in the eye, redness, and swollen eyelids.
An eye allergy is triggered by the same allergens that trigger hay fever. They include pollen, dust, and animal dander.
The first line of treatment is with antihistamine eye drops, which will ease the itching and watering of the eyes. These drops have to be used 3 to 4 times a day.
Ketorolac (Acular, Acuvail) are NSAIDs eye drops that reduce the inflammation and give quick relief.
More severe forms of eye inflammation may require steroid eye drops available on prescription such as loteprednol (Alrex, Lotemax). Doctors don’t recommend the use of steroid eye drops for long periods because they can give you cataract, eye infections, and glaucoma.
OTC decongestant eye drops are advised to reduce the redness of the eyes. Examples include Naphazoline HCL (Clear Eyes) and Phenylephrine HCL (Refresh)
Drugs to treat respiratory allergies
For allergic rhinitis (hay fever), use an OTC decongestant and oral OTC antihistamine. If necessary, use an OTC nasal spray.
- Antihistamines and analgesics (for accompanying fever or a headache) such as Actifed.
- Decongestants like pseudoephedrine are given to clear a blocked nasal passage.
- Antihistamines and steroid eye drops may be required for accompanying conjunctivitis.
- Antibiotics may be required for any super-added bacterial infection.
- Decongestant and/or steroid nasal sprays are also used to clear a blocked nasal passage. Inhalation of vapor is also useful. Steroids play an important role in reducing any inflammation that may be present.
Allergic sinusitis is treated with oral antihistamines and nasal decongestant sprays to clear the blocked nasal passages. Oral antibiotics may be necessary in case the sinuses are infected. Steam inhalation helps to soften up and drain the mucus in the sinuses. Topical nasal steroids may be necessary for inflammation not controlled by nasal decongestants.
Bronchial asthma, an allergic manifestation of respiratory tract allergy causes respiratory distress to the person due to the narrowing of the airway passages. This airway constriction is the direct result of an allergic reaction due to inhalation of an allergen.
Drugs to treat bronchial asthma are classified into short-acting medications to give quick relief from symptoms and long-term drugs to prevent further attacks.
Oxygen is given if saturation falls below 92%
Fast-acting medications for quick relief include beta2-adrenoceptor agonists (SABA), such as salbutamol, which form the first line of treating an acute attack. Salbutamol, also known as albuterol opens up the medium and large airways in the lungs. It is available as an inhaler or nebulizer but is also available as a pill and intravenous solution.
Anticholinergic medications, such as ipratropium bromide are at times given in combination with SABA to control stubborn symptoms in moderate to severe cases.
For the long-term control of asthma symptoms, inhaled form corticosteroids such as betamethasone are the most effective. Oral steroids may be added if required in persistent cases. Prednisolone is prescribed for five days.
Long-acting beta-adrenoceptor agonists (LABA) such as salmeterol are given in combination with oral steroids to better control asthma symptoms. The FDA has recommended that LABAs be used only in conjunction with inhaled steroids in asthma.
Intravenous steroids are used in severe and stubborn cases of asthma where oral steroids do not give relief. These medications include prednisone and methylprednisolone, which reduce the severe inflammation n the airway passages.
Drugs to treat food allergies
- Avoid foods that cause you allergies. Before buying anything off the shelf, remember to read the label on the container carefully and try to identify if your allergen is present or not.
- Mild to moderate symptoms of food allergy (e.g., itching, sneezing, hives, and rashes) are treated with topical antihistamines and steroids. Oral routes of these drugs may be required in stubborn cases where topicals do not give the desired effect.
- Loose motions are treated with antibiotics and/or anti-amoebic drugs if such infection is found in the stool examination.
- Vomiting is treated with anti-emetics like stemetil.
- As for abdominal pain, antispasmodics are given to ease the pain.
- Anti-flatulent antacids are also added for flatulence.
- Severe anaphylactic reactions can arise with ingestion of strong food allergens such as prawns or after injection of the drug penicillin and their treatment is discussed below.
2. Treatment of anaphylactic shock
Anaphylaxis is an emergency and is treated as such.
- Lay the patient flat
- Admit in ICU
- Monitor: Pulse oximetry, ECG, BP
- The patient is put on high-flow oxygen
- Injection epinephrine (adrenaline) is administered IM. Adult IM dose 0.5 mg IM (0.5 mL of 1:1000) adrenaline
- Intravenous (IV) antihistamines in adults and age >12 years: 10 mg IM or IV slowly.
- IV cortisone is administered to reduce the inflammation in the air passages and clear the passages. Dose: >12 years and adults: 200 mg IM or IV slowly
- A beta-agonist (such as albuterol) to relieve difficulty in breathing
3. Immunotherapy- Allergy shots
For those of us, who suffer from allergy symptoms for three months or more per year and with troublesome symptoms, immunotherapy or allergy shots is a recommended form of allergy treatment.
This therapy for allergy involves injecting small amounts of the allergen you are allergic to into your upper arm. This is done once or twice a week for several months.
The dose of the allergen is gradually increased to a maintenance level. Once the maintenance dose is reached, you will receive one dose every two to four weeks for several months.
At an appropriate time, your doctor will then give you the shot every month for 3 to 5 years.
By this time, your body stops seeing the allergen as a foreign substance and stops reacting to it or at least the severity of the symptoms of the allergy reaction reduce considerably.
Allergy shots work well for people who are allergic to bee stings, pollen, dust mites, mold, and pet dander.
Here the immunotherapy is rather rushed with doses being given initially every few hours instead of every few days in a rush to get to the maintenance dose quickly. During rush immunotherapy, your doctor monitors you closely as this form of immunotherapy is risky in people with heart and/or lung disease.