Allergic rhinitis is the way some people respond to outdoor or indoor allergens. Outdoor triggers of allergic rhinitis include ragweed, grass, tree pollen, and mold spores. Indoor triggers include dust mites, pet dander, or mold that grows in humid indoor places such as carpets. Outdoor allergens cause seasonal allergic rhinitis (also known as hay fever), which typically occurs during the spring and summer. Indoor allergens can cause perennial (year-round) allergic rhinitis.
Allergic rhinitis tends to run in families. If one or both parents have allergic rhinitis, there is a high likelihood that their children will also have allergic rhinitis. People with allergic rhinitis have an increased risk of developing asthma and other allergies. They are also at risk for developing sinusitis, sleep disorders (including snoring and sleep apnea), nasal polyps, and ear infections.
Common symptoms of allergic rhinitis include:
Home remedies for allergic rhinitis include nasal washes with a saline solution. Many different over-the-counter and prescription drugs are used to treat allergic rhinitis. These medications include oral and nasal antihistamines, corticosteroid nasal sprays, cromolyn, leukotriene antagonists such as montelukast (Singulair), and decongestants. Many of these drugs have side effects. Immunotherapy (“allergy shots”) may also be an option for some patients.
In addition to avoiding exposure to allergy triggers, people with allergic rhinitis can take precautions to control their environment. These measures include washing animals weekly, using vacuum cleaners and air conditioners with high efficiency particulate air (HEPA) filters, frequent washing of bedding and curtains, reducing humidity in the house, and removing sources of mold.
In 2012, the FDA approved a new nasal spray to treat seasonal allergic rhinitis in patients ages 12 and older. Dymista is a combination of the antihistamine azelastine (Astelin, Astepro) and the corticosteroid fluticasone (Flonase, generic).
The nose is separated into two passages by a wall of cartilage called the septum. The nasal passages are lined with a membrane that produces a clear liquid called mucus. Mucus is a one of the body's defense systems:
If the congestion becomes severe or other changes occur that irritate the nasal passage, rhinitis develops. Rhinitis is inflammation of the nasal passages. To be diagnosed with rhinitis, a patient must experience at least two of the following symptoms for an hour or more on most days:
These symptoms may occur as a result of colds or environmental irritants such as allergens, cigarette smoke, chemicals, changes in temperature, stress, exercise, or other factors.
Acute Rhinitis. If symptoms last fewer than 6 weeks, the condition is referred to as acute rhinitis and is usually caused by a cold or infection, or temporary overexposure to environmental chemicals or pollutants.
Chronic Rhinitis. When rhinitis lasts for a longer period, the condition is called chronic rhinitis. Allergies are often the cause, but structural problems or chronic infections could also be to blame.
Allergic Rhinitis. Allergic rhinitis is rhinitis caused by allergens, which are substances that trigger an allergic response. Allergens involved in allergic rhinitis come from either outdoor or indoor substances. Outdoor allergens such as pollen or mold spores are usually the cause of seasonal allergic rhinitis (also called hay fever). Indoor allergens such as animal dander or dust mites are common causes of perennial (year-round) allergic rhinitis.
The allergic process, called atopy, occurs when the body overreacts to a substance that it senses as a foreign “invader". The immune system works continuously to protect the body from potentially dangerous intruders such as bacteria, viruses, and toxins. However, for reasons not completely understood, some people are hypersensitive to substances that are typically harmless. When the immune system inaccurately identifies these substances (allergens) as harmful, an allergic reaction and inflammatory response occurs.
There are many types of IgE antibodies, and each are associated with a specific allergen. This is why some people are allergic to cat dander, while others are not bothered by cats yet are allergic to pollen. In allergic rhinitis, the allergic reaction begins when an allergen comes into contact with the mucous membranes in the lining of the nose.
Seasonal allergic rhinitis occurs only during periods of intense airborne pollen or spores. It is commonly, although inaccurately, called hay fever. No fever accompanies this condition, and the allergic response is not dependent on hay. In general, triggers of seasonal allergy in the U.S. include:
Allergens in the House. Allergens in the house can trigger attacks in people with year-long allergic rhinitis, called perennial rhinitis. Household allergens include:
Aging Process. The elderly are at risk for chronic rhinitis as the mucous membranes become dry with age. In addition, the cartilage supporting the nasal passages weakens, causing changes in airflow.
Irritative Rhinitis. Irritative rhinitis is caused by an overreaction to irritants, such as cigarette smoke or other air pollutants, strong odors, alcoholic beverages, and exposure to cold. The nasal passages become red and engorged. This reaction is not the same as an allergic reaction, although both are associated with increased numbers of white blood cells called eosinophils.
Vasomotor Rhinitis. Vasomotor rhinitis, another type of nonallergic rhinitis, is caused by oversensitive blood vessels and nerve cells in the nasal passages. It occurs in response to various triggers, including smoke, environmental toxins, changes in temperature and humidity, stress, and even sexual arousal. Symptoms of vasomotor rhinitis are similar to most of those caused by allergies, but eye irritation does not occur.
Blockage in the Nose from Polyps or Structural Abnormalities. A number of conditions may block the nasal passages. Surgery may be helpful for certain cases.
Drugs. A number of drugs can cause rhinitis or worsen it in people with conditions such as deviated septum, allergies, or vasomotor rhinitis:
Estrogen in Women. Elevated levels of estrogen appear to increase mucus production and swelling in the nasal passages and can cause congestion. This effect is most apparent in women during pregnancy and usually clears up after delivery. Oral contraceptives and hormone replacement therapies that contain estrogen may also cause nasal congestion in some women.
Allergic rhinitis affects people of all ages. Allergies usually first appear in childhood. Allergic rhinitis is the most common chronic condition in childhood, although it can develop at any age. About 20% of allergic rhinitis cases are due to seasonal allergies, 40% to perennial (chronic) rhinitis, and the rest are mixed.
Allergic rhinitis appears to have a genetic component. People with a parent who has allergic rhinitis have an increased risk of developing allergic rhinitis themselves. The risk increases significantly if both parents have allergic rhinitis.
Home or workplace environments can increase the risk for exposure to allergens (mold spores, dust mites, and animal dander) associated with allergic rhinitis.
Exclusively breastfeeding for the first 4 months of life can help prevent or delay wheezing and atopic dermatitis in high-risk infants. Some types of infant formulas that are made without cow's milk may possibly help prevent allergies. (There is no evidence that soy-based formulas are helpful.) Solid foods should not be introduced until an infant is 4 - 6 months old. Alterations in a mother's diet do not appear to affect her baby's risk for developing allergies.
Seasonal allergic rhinitis tends to diminish as a person ages. The earlier the symptoms start, the greater the chances for improvement. People who develop seasonal allergic rhinitis in early childhood tend not to have the allergy in adulthood. In some cases, allergies go into remission for years and then return later in life. People who develop allergies after age 20, however, tend to continue to have allergic rhinitis at least into middle age.
Although allergic rhinitis is not considered a serious condition, it can interfere with many important aspects of life. Nasal allergy sufferers often feel tired, miserable, or irritable. Allergic rhinitis can interfere with work or school performance.
People with allergic rhinitis, particularly those with perennial allergic rhinitis, may experience sleep disorders and daytime fatigue. Often they attribute this to allergy medication, but congestion may be the cause of these symptoms. Patients who have severe allergic rhinitis tend to have worse sleep problems, including snoring, than those with mild allergic rhinitis.
Asthma and allergies often coexist. Patients with allergic rhinitis often have asthma or are increased risk of developing it. Allergic rhinitis is also associated with eczema (atopic dermatitis), an allergic skin reaction characterized by itching, scaling, and red swollen skin. Chronic uncontrolled allergic rhinitis can worsen asthma attacks and eczema.
Any chronic rhinitis, whether allergic or nonallergic, can cause swelling in the turbinates, which may become persistent (turbinate hypertrophy). The turbinates are tiny shelf-like bony structures that project into the nasal passageways. They help warm, humidify, and clean the air that passes over them. If turbinate hypertrophy develops, it causes persistent nasal congestion and, sometimes, pressure and headache in the middle of the face and forehead. This condition may require surgery.
Other possible complications of allergic rhinitis include:
The general symptoms of rhinitis are congestion, runny nose, and postnasal drip, in which mucus drips into the throat from the back of the nasal passage, especially when lying on the back. Symptoms may vary depending on the cause of rhinitis. Symptoms of influenza and sinusitis must also be differentiated from allergies and colds.
Symptoms of allergic rhinitis occur in two phases, early and late.
Early Phase Symptoms. The early phase occurs within minutes of exposure to the allergens and includes:
Late-Phase Symptoms. The late phase occurs 4 - 8 hours later and may include one or more of these symptoms:
In most cases, a diagnosis of allergic rhinitis can be established on the basis of the patient's symptoms without any testing. Allergy testing may be used to confirm an allergic trigger identified by symptoms. The doctor will ask about:
The doctor may examine the inside of the nose with an instrument called a speculum. This is a painless examination allowing the doctor to check for redness and other signs of inflammation. The doctor will also usually check the eyes, ears, and chest.
Possible physical findings may include:
A skin test is a simple method for detecting common allergens. Patients are usually tested for a panel of common allergens. Skin tests are rarely needed to diagnose milder seasonal allergic symptoms before a trial of treatment. The skin test is not appropriate for children younger than age 3.
The procedure is as follows:
The test is not completely accurate. In most situations, before testing occurs patients will have tried to avoid any of their known allergens, as well as tried medications, often including nasal corticosteroid sprays. However, patients with more severe symptoms, particularly those with asthma, significant eczema, or nasal polyps, may benefit from earlier skin testing.
Nasal Smear. The doctor may take a nasal smear. The nasal secretion is examined microscopically for factors that might indicate a cause, such as increased numbers of white blood cells, indicating infection, or high counts of eosinophils. High eosinophil counts indicate an allergic condition, but low counts do not rule out allergic rhinitis.
Tests for IgE. Blood tests for IgE immunoglobulin production may also be performed. Newer enzyme-based assays using IgE antibodies have replaced an older test called RAST (radioallergosorbent test). The tests detect increased levels of allergen-specific IgE in response to particular allergens. Blood tests for IgE may be less accurate than skin tests. They should be performed only on patients who cannot undergo skin testing or when skin test results are uncertain.
In people with chronic rhinitis, the doctor may also check for sinusitis. Imaging tests may be useful if other tests are ambiguous. Computed tomography (CT) scans may be useful for some cases of suspected sinusitis or sinus polyps.
In some cases of chronic or unresponsive seasonal rhinitis, a doctor may use endoscopy to examine for any irregularities in the nose structure. Endoscopy uses a tube inserted through the nose that contains a miniature camera to view the passageways.
If rhinitis symptoms are caused by non-allergic conditions, particularly if there are accompanying symptoms indicating a serious problem, the doctor should treat any underlying disorders. If rhinitis is caused by medications, such as decongestants, the patient may need to stop taking them or find alternatives.
A variety of factors must be considered in selecting a treatment approach. These include:
Patients with allergic rhinitis have many treatment options available to them:
All drug treatments have side effects, some very unpleasant and, in rare cases, serious. Patients may need to try different drugs until they find one that relieves symptoms without producing excessively distressing side effects.
Because seasonal allergies generally last only a few weeks, most doctors do not recommend the stronger prescription treatments for children.
Treating Mild Allergy Attacks. Treating mild allergy attacks usually involves little more than reducing exposure to allergens and using a nasal wash. Dozens of treatments are available for allergic rhinitis. Many are available over-the-counter, but some require a prescription. They include:
Because seasonal allergies generally last only a few weeks, most doctors do not recommend the stronger prescription medications for children. However, in children with both asthma and allergies, treatments for allergic rhinitis may also improve asthma symptoms.
Treating Moderate-to-Severe Allergic Rhinitis. Patients with chronic allergic rhinitis or those who have bothersome symptoms that active during most of the year (particularly if they also have asthma) may require daily medications. These drugs include:
For mild allergic rhinitis, a nasal wash can help remove mucus from the nose. You can purchase a saline solution at a drug store or make one at home (2 cups of warm water, a teaspoon salt, pinch of baking soda). Over-the-counter saline nasal sprays that contain benzalkonium chloride as a preservative may actually worsen symptoms.
Here is a simple method for administering a nasal wash:
Neti pots have also become popular in recent years for prevention and treatment of allergic rhinitis. Nasal irrigation with a saline solution through a neti pot involves:
Antihistamine pills can sometimes help itching and redness in the eyes. Eye drops, however, provide faster relief, and a combination of the two may be best. Eye drops for itchy eyes include.
General Side Effects and Warnings.
Histamine is one of the chemicals released when antibodies overreact to allergens. It is the cause of many symptoms of allergic rhinitis. Antihistamines can help relieve:
If possible, take an antihistamine before an anticipated allergy attack.
Many antihistamines are available. They include short-acting and long-acting forms, and come in oral pill and nasal spray forms.
Antihistamines are generally categorized as first- and second-generation. First-generation antihistamines, which include diphenhydramine (Benadryl, generic) and clemastine (Tavist, generic) cause more side effects (such as drowsiness) than most newer second-generation antihistamines. For this reason, second-generation antihistamines are generally preferred and recommended over first-generation antihistamines.
There are some notes of caution when taking any antihistamine:
Second-generation antihistamines are sometimes referred to collectively as nonsedating antihistamines. However, cetirizine (Zyrtec, generic) and the nasal spray antihistamines (Astelin, Patanase) may cause drowsiness when taken at recommended doses. Loratidine (Claritin, generic) and desloratadine (Clarinex) can cause drowsiness when taken at doses exceeding the recommended dose.
Brand Names. Second-generation antihistamines in pill form include:
Second-generation antihistamines in nasal form are as good as or better than the oral forms for treatment of seasonal allergic rhinitis. However, they can cause drowsiness, and are not as effective for allergic rhinitis as nasal corticosteroids. Nasal spray antihistamines are available by prescription and include:
Side Effects and Precautions.
Corticosteroids help reduce the inflammatory response associated with allergic reactions. Nasal-spray corticosteroids (commonly called steroids) are considered the most effective drugs for controlling the symptoms of moderate-to-severe allergic rhinitis. They are often used either alone or in combination with second-generation oral antihistamines. The benefits of nasal spray steroids include:
Nasal-Spray Brands. Corticosteroids available in nasal spray form include:
Side Effects. Corticosteroids are powerful anti-inflammatory drugs. Although oral steroids can have many side effects, the nasal-spray form affects only local areas and has less risk for widespread side effects unless the drug is used excessively. Side effects of nasal steroids may include:
Possible Long-Term Complications. All corticosteroids suppress stress hormones. This effect can produce some serious long-term complications in people who take oral steroids. Researchers have found far fewer concerns with nasal administration or inhaled forms, but there may be certain problems:
Cromolyn serves as both an anti-inflammatory drug and a specific blocker for allergens. The standard cromolyn nasal spray (Nasalcrom, generic) is not as effective as steroid nasal sprays but does work well for many people with mild allergies. It is one of the preferred first-line therapies for pregnant women with mild allergic rhinitis. It may take up to three weeks to experience full benefit.
Side Effects. Cromolyn has no major side effects, but minor ones include nasal congestion, coughing, sneezing, wheezing, nausea, nosebleeds, and dry throat. The spray can cause burning or irritation.
Leukotriene antagonists are oral drugs that block leukotrienes, powerful immune system factors that cause airway constriction and mucus production in allergy-related asthma. They appear to work as well as antihistamines for treatment of allergic rhinitis, but are not as effective as nasal corticosteroids.
Leukotriene antagonists include zafirlukast (Accolate) and montelukast (Singulair). These drugs are mainly used to treat asthma. Montelukast is also approved to treat seasonal allergies and indoor allergies.
The FDA warns that these drugs have been associated with behavior and mood changes, including agitation, aggression, anxiousness, dream abnormalities, hallucinations, depression, insomnia, irritability, restlessness, tremor, and suicidal thinking and behavior. Patients who take a leukotriene antagonist drug such as montelukast should be monitored for signs of behavioral and mood changes. Doctors should consider discontinuing the drug if patients exhibit any of these symptoms.
Decongestants work by shrinking blood vessels in the nose. Many over-the-counter decongestants are available, which can be either taken by mouth or applied to the nose.
Nasal Decongestants. Nasal-delivery decongestants are applied directly into the nasal passages with a spray, gel, drops, or vapors. Nasal decongestants come in long-acting or short-acting forms. The effects of short-acting decongestants last about 4 hours. Long-acting decongestants last 6 - 12 hours. The active ingredients in nasal decongestants include oxymetazoline, xylometazoline, and phenylephrine. Nasal forms work faster than oral decongestants and may not cause as much drowsiness. However, they can cause dependency and rebound.
The major problem with nasal-delivery decongestants, particularly long-acting forms, is a cycle of dependency and rebound effects. The 12-hour brands pose a particular risk for this effect.
The following precautions are important for people taking nasal decongestants:
Oral Decongestants. Oral decongestants also come in many brands, which have similar ingredients. The most common active ingredients are pseudoephedrine (Sudafed, other brands, generic) and phenylephrine, sometimes in combination with an antihistamine. Oral decongestants can cause side effects such as insomnia, irritability, nervousness, and heart palpitations. Taking pseudoephedrine in the morning, as opposed to later in the day or before bedtime, can help patients avoid these side effects.
Individuals at Risk for Complications from Decongestants. People who may be at higher risk for complications are those with certain medical conditions, including disorders that make blood vessels highly susceptible to contraction. Such conditions include:
No one with these conditions should use oral or nasal decongestants without a doctor's guidance. Other people who should not use decongestants without first consulting a doctor include:
Decongestants can cause dangerous interactions when combined with certain types of medications, such as the antidepressant MAO inhibitors. They can also serious problems when combined with methamphetamines or diet pills. Be sure to tell your doctor about any drug or herbal remedy you are taking. Caffeine can also increase the stimulant side effects of pseudoephedrine.
Ipratropium bromide (Atrovent, generic) is a prescription nasal spray that can help relieve runny nose. It works best when given in combination with a nasal corticosteroid. Side effects include nasal dryness, nosebleeds, and sore throat. It should not be used by people who have glaucoma or men who have an enlarged prostate gland.
Immunotherapy (commonly called "allergy shots") is a safe and effective treatment for patients with allergies. It is based on the premise that people who receive injections of a specific allergen will lose sensitivity to that allergen. The most common allergens for which shots are given are house dust, cat dander, grass pollen, and mold.
Immunotherapy benefits include:
Candidates for Immunotherapy. Immunotherapy may be given to anyone with allergies that do not get better with medication and who has had a positive allergy test to specific allergens. The latest guidelines indicate that immunotherapy is safe for young children. Immunotherapy is safe for pregnant women who are already receiving it, although half-strength doses are generally recommended, and it should not be started during pregnancy.
Individuals at Risk for Complications. People who should probably avoid immunotherapy include those who have:
The major downside to immunotherapy is that it requires a prolonged course of weekly injections. The process generally includes:
After stopping immunotherapy, about a third of allergy sufferers no longer have any symptoms, a third have improved symptoms, and a third relapse.
The use of an injection series is effective, but patients often fail to comply with the regimens. Some other schedules and delivery methods are being investigated that might make the program easier.
Rush Immunotherapy. Investigators are studying "rush immunotherapy," in which patients achieve the full maintenance dose with several shots a day over a period of 3 - 5 days. Rush therapy uses modifications that reduce the risk of severe reactions to excessive doses. Studies suggest that it is effective and safe, but anaphylaxis and severe reactions can occur. Patients must be selected carefully and must be monitored closely during this period for severe reactions.
Oral Forms. Trials are underway to test forms of immunotherapy taken by mouth as an alternative to allergy shots. These methods include using a pill taken by mouth or a sublingual (under-the-tongue) tablet. Although sublingual immunotherapy is prescribed in many countries in Europe and South America, it is not approved in the United States and is not considered accepted therapy at this time.
Injections for ragweed and, sometimes, dust mites have higher risks for side effects than other allergy shots. If complications or allergic reactions develop, they usually occur within 20 minutes, although some can develop up to 2 hours after the shot is given.
Side effects of immunotherapy include:
People with existing allergies should avoid irritants or allergens. These triggers include:
Some studies suggest that early exposure to some of these allergens, including dust mites and pets, may actually prevent allergies from developing in children.
Controlling Pets. People who already have pets and are not allergic to them are probably at low risk for developing such allergies later on. When children are exposed to more than one dog or cat during their first year, they have a much lower risk for not only pet allergies but also seasonal allergies and asthma. (Pet exposure does not protect them from other allergens, notably dust mites and cockroaches).
For children who have an existing allergy to pets:
Preventing Exposure to Cigarette and Cooking Smoke. Parents who smoke should quit. Studies show that exposure to second-hand smoke in the home increases the risk for asthma and asthma-related emergency room visits in children. [For help in quitting, see In-Depth Report # 41: Smoking.]
Controlling Dust. Spray furniture polish is very effective for reducing both dust and allergens. Air cleaners, filters for air conditioners, and vacuum cleaners with High Efficiency Particulate Air (HEPA) filters can help remove particles and small allergens found indoors. Neither vacuuming nor the use of anti-mite carpet shampoo, however, is effective in removing mites in house dust. Vacuuming actually stirs up both mites and cat allergens. People with these types of allergies should avoid having carpets or rugs in their homes. For children with allergies, vacuuming should be performed when the child is not around.
Bedding and Curtains.
Reducing Humidity in the House. Living in a damp environment is counterproductive.
Exterminating Pests (Cockroaches and Mice).
Avoiding Outdoor Allergens. The following are some recommendations for avoiding allergens outside:
Some evidence suggests that people with allergic rhinitis and asthma may benefit from a diet rich in omega-3 fatty acids (found in fish, almonds, walnuts, pumpkin, and flax seeds) and fruits and vegetables (at least five servings a day). Researchers are also studying probiotics -- so-called good bacteria, such as lactobacillus and bifidobacterium-- which can be obtained in supplements. Some studies have found that probiotics may help reduce allergic rhinitis symptom severity and medication use.
Al Sayyad JJ, Fedorowicz Z, Alhashimi D, Jamal A. Topical nasal steroids for intermittent and persistent allergic rhinitis in children. Cochrane Database Syst Rev. 2007 Jan 24;(1):CD003163.
Bahls C. In the clinic. Allergic rhinitis. Ann Intern Med. 2007 Apr 3;146(7):ITC4-1-ITC4-16.
Blaiss MS. Safety co