Allergic Rhinitis: An overview and treatment guidelines

Allergy:
“Allergy” is an individual‘s sensitivity to a foreign substance that is usually harmless. This substance, called an allergen or antigen, which is introduced in the immune system by a number of different routes; either by ingestion, inhalation, injection, or simply by touch. Once an allergic individual’s immune system has identified an antigen, it sets to work producing antibodies to defend it. Normal individuals produce Immunoglobin-G (IgG) to ward off invaders. It does not cause an allergic reaction. Allergic individuals also produce IgG but – in addition –they produce Ig E, an antibody with a “memory” for specific substance. Histamine, and related substances, cause allergic symptoms to occur. This is a vastly simplified expansion of allergic reaction. There are many chemicals that become part of the allergy chain. An allergic reaction can occur almost anywhere in body. The symptoms of the reaction often occur at the site of the reaction.

Rhinitis:
Rhinitis is the inflammation of the nasal mucous membrane.
Rhinitis describes a group of symptoms, including runny nose, itching and sneezing that are caused by irritation and congestion in the nose.

Allergic Rhinitis:
Allergic Rhinitis is an inflammation of the nasal passages caused by allergic reaction to airborne substances.
Allergic Rhinitis must be regarded as a serious condition, because it can impact negatively on the quality of life of sufferers not only by producing severe symptoms but also by producing complications. School and work related dysfunction is common.

Classification:
Allergic Rhinitis is often classified into two types; viz, Seasonal & perennial.
Seasonal Allergic Rhinitis:
Seasonal allergic rhinitis is a specific allergic reaction of the nasal mucosa principally to pollens. It can be due to grass & fungal spores also. The symptoms are periodic in nature, usually occurs in spring, early summer & with the change of season.
Perennial Allergic Rhinitis:
Symptoms are due to sensitivity to and contact with allergens which are present in the environment throughout the year. It is usually caused by home or workplace airborne pollutants, while symptoms of perennial allergic rhinitis worst after spending time indoors. These are usually indoor allergens such as homes – dust mites, animal dander, feathers, fungal spores and cockroaches.
Other potential causes of perennial Allergic Rhinitis are: Cigarette smoke, Perfume, Cleansers, Copier chemicals, Industrial chemicals, and Construction material, gases etc.

Causative Factors of Allergic Rhinitis:
(1) Age: Usually it affects young adults from the age of 15 years onwards, and tends to recede after the age of 40 to 50 years.
(2) Sex: Both sexes are affected.
(3) Predisposing Factors:
The factors which predispose the tissues to allergy may be classified in the following way –
1). Hereditary (the most important single factor) & body constitution: 50% of allergic patients give family histories of allergy 2). Infection & Intoxication: The direct action of bacteria & viruses, or their products on the tissue cells, constitutes one of the most important predisposing factors. 3). Endocrine factors: Menstruation, the menopause & ovarian dysfunction, all tends to increase allergic reactions; pregnancy usually reduces asthma, but increases nasal allergy. In hyperthyroidism there is a heightened sensitivity of the sympathetic nervous system & a tendency to exudative reactions & allergy in the skin & mucous membranes. 4). Factors interfering with the chemical & physical resistance of the skin or mucous membranes. 5). Trauma: Trauma alone is rarely a major factor, although it obviously plays an important part when allergy develops after an operation on the nose. 6). Seasonal conditions: Places in which the atmosphere is damp and stagnant and even particularly where trees are numerous, are bad for cases of nasal and bronchial allergy. Attacks are often much less severe at high altitudes (over 5000 ft.) in areas where vegetation is scanty, and at sea at a distance beyond the usual reach of the dust, pollen & clouds. 7). Psychological: Psychological factors play a part in the majority of allergic subjects. They may act as the sole cause, as predisposing factors or exciting factors.
Precipitating Factors (Allergens) –

The allergens are of two types:
(a) Exogenous (External agents) (b) Endogenous (Within the body)

Exogenous factor (external agents) – The majority of cases of nasal allergy are due to exogenous allergens. In adults the cause is usually due to inhale; in early childhood, foods are the most common causative factor. The allergens may be single, but are usually multiple. The following allergens may be responsible for the allergic rhinitis.
Inhalants: Which include such items as house dust, mattress & furniturestuffing, blankets & furnishing fabrics & clothing; animal emanations & scales; orris-root, soaps, creams & perfumes; odours of fish, eggs, coffee & citrus fruits. The most common of the inhalants are animal epidermal. Occasionally, allergic rhinitis may be the result of exposure to an occupational allergen.
Ingestants : Such as wheat, milk, eggs, chocolates, fish & citrus fruits.
Contactants : Such as nasal drops & sprays.
Physical agents : Such as winds & draughts, changes in temperature & humidity; smokes & fumes of sulphur, gas, oil & especially burning anthracite & charcoal, microscopical particles such as barley grains & stone dust.
Bacterial allergens: of which the causative organisms are usually staphylococci, pneumococcal or streptococci.
Drugs: of which those commonly causing nasal allergy are acetylsalicylic acid, iodides, quinine, amidopyrine & the sulphonamides.
Endocrine factors: such as occurs in pregnancy, menstruation & at the menopause.
Nervous & metabolic factors:

Endogenous factors (within body): These are classified as,
Emotional & endocrine:
Bacteria, viruses, moulds & parasites: Intestinal helminthes, such as round worms, pin worms, etc. multiplying within body.
Altered tissue proteins, exudates, transudates, inflamed tissues:

Symptoms of Allergic Rhinitis:
General Symptoms:
The major symptoms of allergic rhinitis are –Sneezing, nasal discharge, nasal congestion and nasal itching.
Some patients may not have the complete symptom complex.

• Sneezing is the most characteristic symptom.
• Paroxysms of 10 to 20 sneeze in rapid succession.
• These episodes are especially apt to occur in the morning, & may leave a patient exhausted.
• Sneezing episodes may arise without warning, or they may be preceded by an uncomfortable itching or irritated feeling in the nose.
• Nasal discharge is typically a watery, thin discharge which may be quite profuse & continuous.
• Because of the copious nature of the rhinorrhea, the skin covering the external nares & the upper lip may become irritated & tender.
• Purulent discharge is never seen in uncomplicated allergic rhinitis; its presence indicates secondary infection.
• Nasal congestion, due to swollen turbinates, is a prominent complaint. The nasal obstruction may be intermittent or more troublesome in the evening & at night.
• If the nasal obstruction is severe, interference with aeration & drainage of the paranasal sinuses or eustachain tube may occur, resulting in the complaints of headache or earache.
• Patients may also complain that their hearing is decreased & that sounds muffled.
• With continuous severe nasal congestion, the sense of smell & taste may be lost.
• Nasal itching is also a prominent feature, inducing frequent rubbing of the nose, particularly in children.
• Eye symptoms: Consists of itching and lacrimation.
• Occasionally there may be marked itching of the ears, palate, throat or face which may be extremely annoying. Because of the irritating sensation in the throat & the posterior drainage of the nasal secretion, a hacking, non productive cough may be present.
• Systemic symptoms: Theses are, Weakness, Malaise, Mental depression, Irritability, Fatigue and Anorexia

The symptoms of perennial allergic rhinitis are those of seasonal allergic rhinitis, although they are frequently less severe. This is due to the almost constant exposure to low concentrations of an allergen such as house dust. Symptoms may lead the patients to “Sinus trouble” or “Frequent cold”.
The chronic nasal obstruction may cause –
1. Mouth breathing
2. Snoring
3. Almost constant sniffing
4. Nasal twang to speech
5. Dry, irritated or sore throat
6. Loss of smell & taste

Management (Treatment) of Allergic Rhinitis:
The three basic approaches for the treatment of allergic rhinitis are,
(1) Avoidance,
(2) Pharmacotherapy, and
(3) Immunotherapy.
Treatment should start with avoidance of allergens and environmental controls. In almost all cases, however, some pharmacotherapy is needed because the patient is either unwilling or unable to avoid allergens and control occasional exacerbations of symptoms. For patients with a severe allergy that is not responsive to environmental controls and pharmacotherapy or for those who do not wish to use medication for a lifetime, immunotherapy may be offered.

Avoidance of Allergens and Environmental controls:
Patients who have seasonal allergies should avoid outdoor activities when allergens are in the air. The patient’s house and workplace should be kept as clean as possible. House dust mites thrive in warm humid conditions, and the antigen is found in their faeces. Control measures include removing reservoirs (e.g., stuffed animals, carpets, and heavy drapes), covering bedding with dustmite– proof covers, and washing potential reservoirs in hot water. Frequent vaccuming with a high-efficiency particulate-arresting (HEPA) vaccume and use of acaricides (eg, benzyl benzoate) and products that denature dust mite antigen (e.g., tannic acid) are encouraged. In addition, lowering the relative humidity to less than 50% and lowering the temperature to less than 70°F are helpful in controlling the dust mite population. If removing pets is not feasible, they should be kept outdoors or, at least, out of the bedroom. Also, frequent vaccuming with an HEPA vaccume and washing the animals are helpful in decreasing the allergen load. Moulds are present throughout the year in damp areas, both indoors and outdoors. Attention should be paid to reservoirs such as refrigerator drip pans, areas around air conditioner condensers and under sinks, indoor plants, and decaying vegetation in the yard. The use of a dehumidifier and an HEPA air-filtration system also is encouraged.

Prevention:
Reducing exposure to pollen may improve symptoms of seasonal Allergic Rhinitis. Strategies include the following:

• Stay indoors with windows closed during the morning hours, when pollen levels are highest.
• Keep car windows up while driving.
• Use a surgical face mask when outside.
• Avoid uncut fields.
• Learn which trees are producing pollen in which seasons, and avoid forests at the height of pollen season.
• Wash clothes and hair after being outside.
• Clean air conditioner filters in the home regularly.
• Use electrostatic filters for central air conditioning.
• Moving to a region with lower pollen levels is rarely effective, since new allergies often develop.
• Preventing perennial Allergic Rhinitis requires identification of the responsible allergens.
• Mould spores: Keep the house dry through ventilation and use of dehumidifiers. Use a disinfectant such as dilute bleach to clean surfaces such as bathroom floors and walls. Have ducts cleaned and disinfected. Clean and disinfect air conditioners and coolers. Throw out mouldy or mildewed books, shoes, pillows, or furniture.
• House dust: Vaccume frequently, and change the bag regularly. Use a bag with small pores to catch extra-fine particles. Clean floors and walls with a damp mop. Install electrostatic filters in heating and cooling ducts, and change all filters regularly.
• Animal dander: Avoid contact if possible. Wash hands after contact. Vaccume frequently. Keep pets out of the bedroom, and off furniture, rugs, and other dander-catching surfaces. Have your pets bathed and groomed frequently.

Pharmacotherapy:
Antihistamines:
Antihistamines block the histamine receptors on nasal tissue, decreasing the effect of histamine release by mast cells. They may be used after symptoms appear, though they may be even more effective when used preventively, before symptoms appear. A wide variety of antihistamines are available.
Older antihistamines often produce drowsiness as a major side effect.
Such antihistamines include the following: Diphenhydramine (Benadryl and generics), Chlorpheniramine (Chlor-trimeton and generics), Brompheniramine (Dimetane and generics), Clemastine (Tavist and generics).
Newer antihistamines that do not cause drowsiness are available by prescription and include the following: Astemizole (Hismanal), Loratidine (Claritin), Fexofenadine (Allegra)
Decongestants:
Decongestants constrict blood vessels to counteract the effects of histamine. Nasal sprays are available that can be applied directly to the nasal lining and oral systemic preparations are available. Decongestants are stimulants and may cause increased heart rate and blood pressure, headaches, and agitation. Use of topical decongestants for longer than several days can cause loss of effectiveness and rebound congestion, in which nasal passages become more severely swollen than before treatment.
Topical corticosteroids:
Topical corticosteroids reduce mucous membrane inflammation and are available by prescription. Allergies tend to become worse as the season progresses because the immune system becomes sensitized to particular antigens and can produce a faster, stronger response. Topical corticosteroids are especially effective at reducing this seasonal sensitization because they work more slowly and last longer than most other medication types. As a result, they are best started before allergy season begins. Side effects are usually mild, but may include headaches, nosebleeds, and unpleasant taste sensations.
Mast cell stabilizers:
Cromolyn sodium prevents the release of mast cell granules, thereby preventing release of histamine and the other chemicals contained in them. It acts as a preventive treatment if it is begun several weeks before the onset of the allergy season. It can be used for perennial Allergic Rhinitis as well.

Immunotherapy:
Immunotherapy, also known as desensitization or allergy shots, alters the balance of antibody types in the body, thereby reducing the ability of IgE to cause allergic reactions. Immunotherapy is preceded by allergy testing to determine the precise allergens responsible. Injections involve very small but gradually increasing amounts of allergen, over several weeks or months, with periodic boosters. Full benefits may take up to several years to achieve and are not seen at all in about one in five patients. Individuals receiving all shots will be monitored closely following each shot because of the small risk of anaphylaxis, a condition that can result in difficulty breathing and a sharp drop in blood pressure. Immunotherapy is indicated in patients whose symptoms are not well controlled with avoidance measures and pharmacotherapy. It also is appropriate for those with symptoms lasting more than 1 season and documented allergen-specific IgE antibodies. Immunotherapy should be considered only in individuals who can comply with weekly injections for approximately 3 years. Immunotherapy should be avoided in those receiving beta-blockers and those who have poorly controlled asthma, autoimmune disorders, or immunodeficiency disorders. During pregnancy, injections should not be initiated, and doses should not be increased. Although the exact mechanisms of immunotherapy are not known, they are associated with decreased allergen-specific IgE levels and increased allergen-specific immunoglobulin G (IgG) levels. These IgG molecules are thought to be blocking antibodies that are important in impeding the allergic reaction. Immunotherapy involves regular injections (every 5-7 days) of increasing amounts of each reacting allergen until the symptoms are relieved or the maximum tolerated dose is reached, at which time a maintenance dose is given every 2-4 weeks. This dose is maintained until symptoms are controlled for 2-3 seasons and then tapered. Although systemic reactions are rare when immunotherapy is properly administered, only qualified personnel should give injections, and resuscitative equipment should be available.

Surgical Care:
Although Allergic Rhinitis is a medical condition, adjunctive surgery may be offered to alleviate obstructive symptoms in appropriate individuals.

Diet:
Food allergies can cause nasal symptoms similar to those caused by inhalant allergies. Therefore, a workup for possible food allergies should be considered if the patient has a history of food reactions, if findings of the inhalant allergy evaluation are negative, and if appropriate treatments fail to yield improvement.

Ayurvedic treatment of Allergic Rhinitis:
It can be divided into two parts:
1) Samanya (General treatment)
2) Vishesh (Specific treatment)
Samanya Chikitsa(General treatment):According to Ayurveda, five diseases, diseases of eye, diseases related with digestive track, diseases of nose, fever and wound are primarily cured by ‘Langan’( Fasting) for five days.
Vishesh Chikitsa(Specific treatment):
All types of rhinitis except of recent origin should be treated by the following measures in Ayurveda.

• Ghritapana: Having of medicated clarified butter.
• Swedana: Hot fomentation
• Vamana: Medicated emesis
• Avapida Nasya: Medicines inserted through nasal route

Treatment of rhinitis of recent origin:
‘Sushruta’(school of Ayurvedic surgery) has given following line of treatment for treatment of rhinitis of recent origin (Ama stage of Pratishyaya).

• Swedana: Hot fomentation
• Intake of warm food which are sour in taste
• Ginger should be taken with milk or with sugarcane
• Drinking water should be boiled
• Dhumapana- Ayurvedic smoking
• Kavalagraha- Gargling of salted water
• Haritaki Sevana- Chewing of fruit of ‘ Terminalia chebula’ or tablet of the same.

Here we also try to concluding some Ayurvedic formulations which are helpful for the treatment of rhinitis.

• Maricha Churna (powder of black pepper) mixed with Jaggery and Curd,
• Kataphaladi Churna
• Vyoshadi Churna
• Sarpi Guda
• Chitraka Haritaki Avleha
• Shadanga Yusha
• Panchamula siddha Ghrita
• Nasya(Nasal drops) by Anu Taila & Shadabindu Taila