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 mucus. Mucus is one of the body's defense systems:
Mucus, a clear, thin liquid, traps small particles and bacteria that are drawn into the nose when the person breathes.
The trapped bacteria are usually harmless in healthy people.
Even under normal circumstances, this produces a cycle of congestion and decongestion that occurs continuously throughout the day.
When one side of the nose is congested, air passes through the open, or decongested, side. The sides alternate between being wide open and narrow.
If the congestion becomes severe or if other changes occur that irritate the nasal passage, rhinitis develops. Rhinitis describes a group of symptoms, including the following:
These symptoms can develop as a result of a cold or environmental irritants, such as allergens, cigarette smoke, chemicals, temperature changes, stress, exercise or other factors.
Infectious rhinitis. If symptoms last less than six weeks, it is called acute rhinitis. It is usually caused by a cold or other infection, or by temporary overexposure to chemicals or environmental pollutants. Infectious rhinitis is discussed in Report No. 94, Colds, Flu and Bronchitis. ]
Chronic rhinitis. When rhinitis lasts longer, it is called chronic rhinitis. It is most often caused by allergies, but can also be caused by structural problems or chronic infections. See Chronic Non-Allergic Rhinitis box].
CAUSES OF CHRONIC NON-ALLERGIC RHINITIS
Some cases of chronic rhinitis are associated with an increase in the number of white blood cells called eosinophils. These are components of the immune system that release powerful inflammatory factors, but are not related to the allergic response. This inflammatory response causes nasal congestion in susceptible individuals and can be triggered by cigarette smoke, dozens of other air pollutants, strong odors, alcoholic beverages and exposure to cold. Elderly people are at risk of chronic rhinitis because the mucous membranes dry out with age.
Vasomotor rhinitis, also sometimes called idiopathic or irritant rhinitis, occurs when the nasal membrane swells in response to irritants, including smoke, environmental toxins, changes in temperature and humidity, and stress. Emotional stress and sexual excitement can also trigger nasal congestion and stuffiness. However, this overreaction is not associated with the immune response and its biological causes are unknown. The symptoms of vasomotor rhinitis are similar to most symptoms caused by allergies. However, they are usually more severe and occur mainly on one side of the nose.
Obstruction in young children is most often caused by foreign objects that they have pushed into their nose. If they stay in place, they can eventually cause an infection and a runny nose, usually on one side of the nose, which may be yellow or green and smelly.
Blockage of the nose by polyps or structural abnormalities
A number of conditions can block the nasal passages.
Polyps. These are soft, gray, fluid-filled sacs that develop from rod-like structures on the mucosa. They prevent mucus from flowing out and restrict airflow. Polyps usually develop as a result of sinus infections that cause the nasal mucosa to overgrow. They do not regress on their own and, in fact, can multiply and cause considerable obstruction.
Deviated septum. A common structural abnormality that causes rhinitis is a deviated septum. The septum is the inner wall made of cartilage and bone that separates the two sides of the nose. When it is deviated, it is not straight but moved to one side, usually to the left.
Other causes of obstruction. In rare cases, cleft palates, overgrowth of the nasal bones or tumors can cause rhinitis.
Surgery may be helpful in some cases. A procedure called radioablation is also being studied. It uses a surgical wand connected to a radio frequency generator that applies energy to different areas of the nose. More research is needed, but researchers involved in a recent study predict that this could be a new wave in the treatment of chronic nasal congestion.
Non-allergic rhinitis in children
Chronic nasal congestion in children is often accompanied by a predisposition to ear, sinus or adenoid infections. Adenoids are masses of spongy tissue located between the ends of the nasal passages and the soft tissues of the back of the throat. Enlarged adenoids can also cause ear problems. However, the bacteria that cause these other infections are not usually the cause of this chronic rhinitis.
Medications and illicit drugs
A number of medications can cause or worsen rhinitis in people with conditions such as deviated septum, allergies or vasomotor rhinitis:
Overuse of decongestant sprays used to treat nasal congestion can, over time (three to five days), cause inflammation of the nasal passages and make rhinitis worse.
Many people with allergies and asthma are sensitive to some of the common painkillers called non-steroidal anti-inflammatory drugs (NSAIDs). These include the common medications aspirin, ibuprofen (Motrin, Advil, Nuprin, Rufen) and naproxen (Aleve). Aspirin and aspirin-containing products can even cause life-threatening asthma attacks in some very sensitive people. NSAIDs vary, however, and some patients may not have a reaction to all of them. For minor pain, acetaminophen (e.g., Tylenol), which is not an NSAID, is generally recommended for patients with NSAID intolerance. A pharmacist should be consulted if the ingredients of over-the-counter preparations are not known.
Other medications that can cause rhinitis include oral contraceptives, hormone replacement therapy, and some blood pressure medications, including beta-blockers and vasodilators.
Snorting cocaine damages the nasal passages and can cause chronic rhinitis.
Hormonal changes in women
Conditions that cause hormonal changes in women, such as pregnancy and hypothyroidism, can cause chronic rhinitis. In these cases, the condition usually disappears after treatment of the disorder or, in the case of pregnancy, at delivery.
People with certain rare genetic diseases or other diseases that affect the mucous membranes are at risk for chronic rhinitis, although rhinitis in these people is only one of many more serious conditions, including chronic sinusitis and respiratory problems. Wegener's granulomatosis, for example, is a serious but very rare disease that causes long-term swelling and tumor masses in the airways.
Rare genetic diseases that cause chronic rhinitis include the following:
Cystic fibrosis, in which the mucus is very thick.
Kartagener's syndrome. In this case, the major internal organs of the body are located in an inverted position from their normal location. In addition, the cilia (hair-like protrusions on many body tissues that help move mucus and other fluids) are weakened or immobile.
In both cases, the buildup of mucus also creates a favorable environment for infection-causing organisms.
WHAT ARE THE CAUSES AND TRIGGERS OF ALLERGIC RHINITIS?
Biological mechanisms that cause allergic rhinitis
The body's immune system is designed to produce a variety of factors to fight foreign substances, including bacteria, viruses and other proteins that the immune system perceives as threatening. An allergic response occurs when the body's immune system overreacts or is hypersensitive to certain non-infectious particles (some experts believe that this hypersensitive response originally developed in humans to fight large invaders, such as parasites and worms).
Among the important components of the immune system are antibodies. Antibodies are classified into five categories, called immunoglobulins (IgG, IgA, IgM, IgD, IgE). Overproduction of IgE antibodies is a key factor in the allergic reaction, which most likely occurs due to genetic factors.
During an allergic attack, IgE antibodies bind to cells called mast cells, which are usually concentrated in the lungs, skin and mucous membranes.
Once IgE antibodies bind to mast cells, these cells are programmed to release a number of chemicals, including histamine.
These chemicals open blood vessels and cause redness of the skin and swelling of the membranes; when these effects occur in the nose, sneezing and congestion occur.
Triggers for seasonal allergic rhinitis (hay fever or rose fever)
Seasonal allergic rhinitis only occurs during periods of high pollen or spore concentration in the air. It is commonly, though inaccurately, called hay fever or rose fever, depending on whether it occurs in late summer or spring. No fever accompanies this condition, and the allergic response is not dependent on either hay or roses. In general, the triggers for seasonal allergy in the United States are:
Ragweed. Ragweed is the leading cause of allergic rhinitis in the U.S. and affects about 75% of allergy sufferers. A single plant can release one million pollen grains per day. Ragweed is found throughout the United States, although it is less prevalent along the West Coast, in southern Florida, northern Maine, Alaska and Hawaii. In the northern states, the effects of ragweed are felt in mid to late August and last until the first frost. Ragweed allergies tend to be most severe before noon.
Grasses. Grasses affect people from mid-May to late June. Grass allergies occur more in the late afternoon.
Tree pollen. Small pollen grains from some trees usually produce symptoms in late March and early April.
Mold spores. Mold spores that grow on fallen leaves and release spores into the air are common allergens in the spring, summer and fall. Mold spores can peak on dry, windy afternoons or on wet or rainy days in the early morning.
Triggers for perennial (year-round) allergic rhinitis
Allergens in the home can cause year-round allergic rhinitis, called perennial rhinitis. Household allergens can include the following:
House dust mites.
Molds that grow on wallpaper, houseplants, carpeting and upholstery.
Other possible triggers of year-round allergies being researched include:
Air pollutants. Although difficult to prove, a number of investigations, including European studies in 1999 and 2000, have reported an association between traffic-related air pollution and allergic rhinitis. Several studies have implicated diesel exhaust particles as having a role in allergic rhinitis.
Bacteria. Although bacteria do not cause allergic rhinitis, one study found a higher number of colonies of the common bacterium Staphylococcus aureus in the nasal passages of patients with perennial rhinitis. The study suggests that the allergic condition may lead to higher bacterial levels, which in turn may worsen allergies.
A flame retardant called triphenyl phosphate, which is used to coat computer monitors, is a known allergen. Newer computers contain more of this compound, but it is not yet known whether this can cause rhinitis or other allergic symptoms in computer users.
WHAT ARE THE SYMPTOMS OF RHINITIS?
The general symptoms of rhinitis are congestion, runny nose and post-nasal drip, which is mucus flowing down the throat from behind the nasal passage, especially when lying on the back. Symptoms may vary depending on the cause of the rhinitis. The symptoms of flu and sinusitis must also be differentiated from those of allergies and colds.
Symptoms of allergic rhinitis include a stuffy nose any of the following:
A runny or congested nose.
Frequent or repetitive sneezing.
Itching in the nose, eyes, throat or roof of the mouth.
Decreased sense of smell.
In some cases, a slight decrease in attention span, deterioration of memory and slowed thinking.
In cases of severe allergies, dark circles under the eye. The lower eyelid may be puffy and wrinkled.
Children can push their nose up with the palm of their hand or make a bunny movement to clear the obstruction.
Interestingly, although people with allergic rhinitis feel like they are getting less air through their nose, one study showed that there was no difference between non-allergic and allergic seasons in total nasal airflow, and that patients can get full airflow during allergy season through one nostril.
WHO GETS ALLERGIC RHINITIS?
Allergic rhinitis is the most common chronic condition in children. In general, about 26 million Americans have seasonal allergic rhinitis and up to 40 million may have mild symptoms. However, it is difficult to estimate the number of people with allergic rhinitis. Studies in the United States report prevalences ranging from 4% to 40%. One reason why studies vary so much may be due to self-reporting. For example, in response to a Spanish survey, only 9.4% of adolescents reported having hay fever or allergic rhinitis, whereas 30.3% described symptoms characteristic of allergic reactions. Regardless, the consensus is that in the United States and worldwide, the numbers are increasing.
Genetic factors are the major determinants of allergies.
If both parents are allergic, the risk to the child is 75%.
If only one parent is allergic, the child's chance is 50%.
It should be noted that children who have a family member with allergies are at the greatest risk of developing allergies themselves, but allergies can develop in anyone.
Age of onset and duration
Although allergies often first appear in childhood, they can develop at any age. In some cases, allergies go into remission for years and then return later in life. People who develop hay fever in early childhood are unlikely to develop the allergy as adults. On the other hand, those who develop it after the age of 20 tend to continue to have hay fever at least into middle age.
Allergic reactions in childhood
Having other allergies increases the risk of allergic rhinitis. Here are some examples:
Young children with eczema (an allergic skin reaction) have a later risk of allergic rhinitis and asthma. In fact, a family history of eczema increases the risk.
Food allergies are associated with allergic rhinitis and asthma (early feeding, timing of weaning and introduction of solid foods have no effect on the risk of developing allergic symptoms. However, some studies suggest that breastfeeding may decrease or delay the risk of allergies).
Allergies and, even worse, asthma are on the rise. A number of international studies have reported an association between more Westernized lifestyles and a greater increase in asthma and allergies, although they are not consistent. Ironically, theories to explain this increase point to healthier conditions in industrialized countries.
Protective role of early respiratory infections. One important theory attributes the dramatic increase in allergies and asthma to the elimination of childhood infections since the widespread use of immunization. The basic theory is this:
In the past, when children were infected with childhood diseases, the immune system released T-1 helper white blood cells (TH1), which stimulated the body's infection fighters.
At the same time, the immune system suppressed the production of T-2 helper cells (TH2). These cells attack airborne allergens and parasites. They also release powerful inflammatory factors that play a major role in the allergic response.
TH2 cells appear to be important in fetal development, but in a normal environment they are replaced by TH1 cells which become more prevalent. With fewer TH2 cells, the child does not react to allergens.
When children are vaccinated (note: vaccines can cause irreversible damage to the brain and body, and the risks far outweigh the benefits. See SPECIAL REPORTS on vaccines. Please review all the evidence for vaccines before deciding to vaccinate yourself or your children), however, TH2 cells remain active (instead of TH1 cells). In genetically susceptible individuals, they continue to trigger inflammatory events in response to allergens.
This theory is supported by studies indicating that being part of a large family or attending daycare increases the risk of early infections but reduces the risk of allergies and childhood asthma. Another study reports that in areas where certain gastrointestinal infections are high due to poor food hygiene, allergies are lower.
It should be noted that exposure to childhood infections does not necessarily prevent the development of allergies, and this theory is not an argument against vaccination. Infections were killing thousands of children each year before vaccination became widespread. Allergic rhinitis is almost never very severe and asthma, although it can be serious, is rarely fatal in children.
Overexposure to indoor allergens. A study in Germany that followed East German children after the country's unification found that children in areas previously under communist rule experienced a significant increase in allergies, particularly hay fever, when exposed to a Western lifestyle. The lifestyle changes included the following
Increase in carpeting.
Increased number of cats.
Margarine consumption (which has been linked to hay fever).
Some scientists believe that children are overexposed to indoor allergens because they now spend three or more hours indoors each day engaged in sedentary activities such as watching television, playing video games or using computers. This exposure is intensified by the recent trend to make homes more energy efficient, which can result in more dust mites being trapped indoors.
In Western countries, however, children living in low-income households appear to be more sensitive to common allergens, such as those from cockroaches. The reason for this is unclear and requires further research.
Month of birth
According to a 1997 study, the month of birth may influence allergy risk:
People born in September, October or November had the highest levels of IgE (a key immune factor in allergies), and thus likely had a higher risk of seasonal allergies.
Those born in June, July and August had the lowest IgE levels.
Interestingly, a more recent Japanese study found a similar seasonal pattern in risk factors for children with skin allergies, but not for those with asthma or allergic rhinitis. If there is a seasonal pattern, it is likely to be small.
HOW SEVERE IS ALLERGIC RHINITIS?
While perennial allergic rhinitis is certainly not considered a serious condition, it can still interfere with many important aspects of life. Seasonal allergic rhinitis tends to decrease with age. The earlier the symptoms appear, the greater the chance of improvement. In one study, more than half of allergy sufferers reported that by age 40, their symptoms had improved, and 23% were symptom-free.
Fatigue and sleepiness
People with allergic rhinitis, especially those with perennial allergic rhinitis, may experience sleep disturbance and daytime fatigue. They often attribute this to medications, but studies suggest that congestion may be the culprit.
Risk of asthma
Children with allergic rhinitis alone appear to have a slightly higher risk of asthma than the general population. Studies have reported that about 1-10% of children with allergic rhinitis have developed asthma as a result. Researchers are finding that cells called eosinophils, which are produced by the immune system and are an important component of asthma, are also present in patients with allergic rhinitis. Although they are much less numerous in patients with allergic rhinitis than in those with asthma, eosinophils cause airway inflammation in the lungs and may be a predisposing factor for the later development of asthma in some patients with allergic rhinitis. In addition, allergic rhinitis has a negative impact on asthma in patients who suffer from both conditions; in fact, studies show that allergen avoidance can reduce the development of asthma.
Increased risk of other allergies
People with allergic rhinitis may have a higher risk of other allergies, including potentially serious food or latex allergies.
Complications of chronic rhinitis in children
Children with severe allergies may have a higher risk of behavioral problems than children without allergies. Some research suggests that allergic rhinitis is responsible for two million missed school days each year.
Year-round allergic rhinitis is associated with ear infections (acute otitis media).
Chronic nasal obstruction due to year-round allergies can affect a child's appearance. If the child can only breathe through the mouth, the continual force of air passing through the oral cavity can alter the developing soft bones of the face, eventually causing an elongated face and overbite due to teeth coming in at an abnormal angle.
Chronic rhinitis can cause headaches and affect a child's sleep, concentration, hearing, appetite and growth.
Associations with other disorders
Chronic fatigue syndrome (CFS). Some, but not all, studies have reported that the majority of CFS patients are allergic to food, pollen, metals (such as nickel or mercury) or other substances. Some research indicates that people with both allergies and emotional disorders, such as anxiety or depression, may be more vulnerable to the effects of the inflammatory response. This is a harmful overreaction of the immune response, which triggers the release of a number of immune factors, which can cause fatigue, joint pain and fever and can also affect the hypothalamus-pituitary-adrenal system in the brain.
One theory that may help link some of the various factors common to CFS suggests that allergies, stress and infections can deplete a chemical in the body called adenosine triphosphate (ATP). This chemical stores energy in cells, and studies have reported a deficiency in many CFS patients. This theory is supported by a study in which patients reported a reduction in CFS symptoms after taking a coenzyme called NADH, which increases ATP levels.
Rheumatoid arthritis. Interestingly, people with allergic rhinitis are less likely to have rheumatoid arthritis and vice versa. Patients with both conditions tend to have less severe arthritic symptoms. Experts suggest that the immune response of one condition may tend to neutralize the other.
WHAT TESTS MAY BE NEEDED TO DIAGNOSE RHINITIS?
Medical and personal history
To determine if allergies are the trigger for rhinitis, the doctor will ask a number of questions. They may include the following:
Whether there is a family history of allergies.
If there is a history of medical problems.
If the patient is taking any medications.
Whether the patient has any pets.
The time of day and year of the allergy attacks. The timing of symptoms helps the doctor make a diagnosis:
Rhinitis that occurs seasonally is almost always due to pollens and outdoor allergens.
If symptoms occur throughout the year, the doctor will suspect perennial allergic or non-allergic rhinitis.
The doctor usually examines the inside of the nose with an instrument called a speculum. This is a painless examination that allows the doctor to check for redness and other signs of inflammation. The doctor will also usually examine the eyes, ears and chest.
Allergy Skin Tests
A skin test is a simple method for detecting common allergens in people. The test is not appropriate for children under the age of 3. The procedure is as follows:
Small amounts of suspected allergens are applied to the skin with a needle or scraper (i.e., a patch test).
Or, small amounts of suspected allergens are injected a few cells deep into the skin (this is the intradermal test). This test may be more sensitive than the standard prick test.
If an allergy occurs, a hive (a red, swollen area) forms in about 20 minutes.
Patients should not take antihistamines for at least 12 to 72 hours before the test. Otherwise, the allergic reaction may not occur. About 15-20% of people may have a skin reaction without actually being allergic. Skin tests are rarely needed to diagnose mild seasonal allergic rhinitis, because the cause is usually obvious. Patients are usually tested for a panel of common allergens.
Nasal swab. The physician may perform a nasal swab. The nasal secretion is examined under a microscope for factors that may indicate a cause, such as an increased white blood cell count, indicating an infection, or an elevated eosinophil count. (A high eosinophil count indicates an allergic condition, but a low count does not rule out allergic rhinitis.)
Tests for IgE. Blood tests for IgE immunoglobulin production can also be done. One of these, called the radioallergosorbent test (RAST), is used to detect an increase in allergen-specific IgE levels in response to particular allergens. Blood tests for IgE can be less accurate than skin tests. They should only be performed in patients who cannot undergo skin testing or when skin test results are uncertain.
In people with chronic rhinitis, the doctor may also look for sinusitis. Imaging tests can be helpful if other tests are ambiguous.
A test called transillumination, in which the doctor shines a bright light on the patient's cheek or forehead, is an inexpensive but not very accurate method of checking for abnormalities in the sinus cavities.
X-rays and CT scans can be helpful in some cases of sinusitis.
In some cases of chronic or refractory seasonal rhinitis, a physician may use endoscopy to examine any irregularities in the structure of the nose. Endoscopy uses a tube inserted through the nose that contains instruments and a miniature camera to view the passageways.
WHAT ARE THE GENERAL GUIDELINES FOR MEDICATIONS USED TO TREAT ALLERGIC RHINITIS?
In most cases of mild allergic rhinitis, reducing exposure to allergens and using a nasal wash is sufficient.
Medications used to treat the symptoms of allergic rhinitis
Dozens of medications are available to treat allergic rhinitis. Many are available over the counter, but some require a prescription:
Medications to relieve symptoms.
Decongestants relieve nasal congestion and itchy eyes.
Medications to prevent allergy attacks
Antihistamine tablets relieve sneezing and itching and can prevent nasal congestion before an allergy attack. They are the first line of prevention at this time.
Nasal corticosteroids (commonly called steroids) reduce inflammation and are now considered the most effective measure to prevent allergy attacks.
Nasal cromolyn also reduces inflammation and may be sufficient in mild cases.
New agents are also being studied. All drug treatments have side effects, some very unpleasant and, in rare cases, serious. Patients may have to try different drugs until they find one that relieves symptoms without producing excessively painful side effects.
Immunotherapy (allergy shots)
Immunotherapy (allergy shots) is the only treatment that works on the cause of allergies and is very effective. It can also prevent asthma and the development of new allergies in children. Many experts now recommend immunotherapy immediately for people with both asthma and allergies.
Special Considerations for Medication Treatment of Children with Allergies
Because seasonal allergies usually last only a few weeks, most doctors do not recommend the strongest prescription treatments for children. However, one study noted that in children with both asthma and allergies, intense treatments for allergic rhinitis can also improve asthmatic symptoms. It is important for parents to determine if the child is truly distressed and if they are not simply reacting to their own anxiety when they hear the child sniffling or snoring. Prescription medications are only needed in certain severe cases.
AGENTS USED FOR ITCHY EYES
Here are some drops for itchy eyes. Others are also available. Clients react differently to these products and report a wide range of effectiveness.
Antihistamine Eye Drops
Levocabastine (Livostin) for relief of nasal symptoms and itchy red eyes.
Decongestant eye drops
Phenylephrine (Allergan Relief).
Naphazoline (Naphcon, Opcon-A, Vasoclear).
Tetrahydrozoline (Murine Plus, Visine, several brands).
Loteprednol (Lotemax, Alrex).
General side effects and warnings
All eye drops can cause stinging and some can cause headaches and congestion.
Eye drops should not be continued if pain, change in vision, worsening of redness or irritation, or if the condition lasts more than three days.
Do not touch the end of the device or other surfaces with it. Replace the cap after use. Discard any solution that changes color or becomes cloudy.
People with heart disease, high blood pressure, enlarged prostate and glaucoma should avoid eye drops.
HOW ARE DECONGESTANTS AND NASAL WASHES USED TO PREVENT ALLERGY SYMPTOMS?
For mild allergic rhinitis, a nasal wash may be helpful to clear mucus from the nose. Decongestants can help dry up nasal congestion. They work by constricting the vessels in the nose. By reducing the blockage, they reduce the risk of developing sinusitis caused by viruses or bacteria. Many over-the-counter decongestants are available, either as tablets, nasal decongestants or inhaled decongestants that are applied directly to the airways as sprays, drops or vapors.
In cases of mild allergic rhinitis, a nasal wash may be helpful to clear mucus from the nose. A saline solution can be purchased at a pharmacy or prepared at home. One study showed that neither a homemade solution (a teaspoon of salt and a pinch of baking soda in a quart of warm water) nor a commercial hypertonic saline nasal wash had any effect on symptoms. Some doctors, however, defend the effectiveness of a traditional nasal wash, used for centuries, which does not use baking soda, but more liquid for each dose and less salt than the saline washes in the study. The process is as follows:
Lean over the sink, head down.
Pour a little solution into the palm of your hand and inhale it through your nose, one nostril at a time.
Spit out the rest of the solution.
Blow your nose gently.
The solution can also be introduced into the nose using a large rubber ear syringe, available in pharmacies. In this case, the process is as follows:
Lean over the sink, head down.
Insert only the tip of the syringe into one nostril.
Gently squeeze the ampoule several times to wash out the nasal passage.
Then press the ampoule down firmly enough that the solution passes into the mouth.
The process should be repeated in the other nostril.
Nasal washing should be done several times a day.
Nasal decongestants are applied directly to the nasal passages in the form of a spray, gel, drop or vapor. Nasal forms work faster than oral decongestants and have fewer side effects. They often require frequent administration, although long-acting forms are now available. The ingredients and brands of nasal decongestants are as follows:
Long-acting nasal decongestants. They are effective within minutes and remain effective for six to 12 hours. The ingredients are as follows:
Oxymetazoline: Brands include Vicks Sinex (12 hour brands), Afrin (12 hour brands), Dristan 12 hour, Good Sense, Nostrilla, Neo-Synephrine 12 hour.
Short-acting nasal decongestants. Effects usually last about four hours.
Phenylephrine: Neo-Synephrine (mild, regular, very potent), 4-Way, Dristan Mist Spray, Vicks Sinex).
Naphazoline (Naphcon Forte, Privine).
Addiction and rebound. The main danger of nasally administered decongestants, especially the long-acting forms, is a cycle of dependence and rebound effects. The 12-hour brands pose a particular risk for this effect. This effect works as follows:
With prolonged use (more than three to five days), nasal decongestants lose their effectiveness and even cause swelling of the nasal passages.
The patient then increases the frequency of use. The congestion worsens and the patient responds with even more frequent doses, in some cases up to every hour.
People then become dependent on these medications.
Tips for use. The following precautions are important for people who take nasal decongestants:
When using a nasal spray, spray each nostril once. Wait one minute to allow absorption by mucosal tissues, then spray again.
Keep nasal passages moist. All forms of nasal decongestants can cause irritation and stinging. They can also dry out the affected areas and damage the tissue.
Do not share droppers and inhalers with others.
Use decongestants only for conditions that require short-term use, such as before air travel or for a one-time allergy attack. Do not take them for more than three days at a time. With prolonged use, nasal decongestants become ineffective and lead to a rebound effect and addiction.
Discard sprays, inhalers or other decongestant delivery devices when you no longer need the medication. Over time, these devices can become reservoirs for bacteria.
Discard the medication if it becomes cloudy or unclear.
Oral decongestants also come in many brands, which are distinguished primarily by their ingredients. Common active ingredients include:
Pseudoephedrine: Sudafed, Actifed, Drixoral. Almost all decongestants and combination remedies now contain pseudoephedrine, since the alternative decongestant, phenylpropanolamine (PPA), has been withdrawn from the market [see below]. Some oral decongestants, such as Nature's Way and others, contain pseudoephedrine derived naturally from the Chinese herb ephedra. The side effects apply to these products as well.
Phenylpropanolamine (PPA). PPA was a common ingredient in many decongestants, but it has been removed from the U.S. market. See warning box, Decongestants and Phenylpropanolamine].
Side effects of decongestants
Some side effects are more likely to occur with oral decongestants than with nasal decongestants, including the following:
Restlessness and nervousness.
Drowsiness (especially with oral decongestants and in combination with alcohol).
Changes in heart rate and blood pressure.
Avoid combining oral decongestants with alcohol or certain medications, including monoamine oxidase inhibitors (MAOIs) and sedatives
People at risk for complications from decongestants. People at higher risk of complications are those with certain medical conditions, including conditions that make blood vessels very sensitive to constriction. These conditions include the following:
High blood pressure. (Oral medications containing pseudoephedrine have less effect on blood pressure than those containing phenylpropanolamine, but both should be avoided by anyone with high blood pressure.)
Prostate problems leading to urinary difficulties.
Strong sensitivity to cold.
Emphysema or chronic bronchitis (These people should especially avoid high-potency, short-acting nasal decongestants).
Anyone with these conditions should not use oral or nasal decongestants without the advice of a physician. Other groups who should also use these agents with caution are:
Anyone who is pregnant should not use these agents without consulting a physician.
Children seem to metabolize decongestants differently than adults. Decongestants should not be used at all in infants and young children, who are particularly susceptible to side effects that depress the central nervous system. These effects include changes in blood pressure, drowsiness, deep sleep and, rarely, coma.
Warning Box: Decongestants and Phenylpropanolamine (PPA)
In response to reports of an increased risk of stroke in young women taking products, including oral decongestants, containing phenylpropanolamine (PPA), the Food and Drug Administration (FDA) began taking steps to ban it from the U.S. market in November 2000.
Many agents contained this product. However, almost all of them have now been removed from the market or reformulated. A number of brands that previously contained PPA have now substituted other active ingredients (usually pseudoephedrine) and are safe to use. These include the following brands:
Alka-Seltzer Plus Cold Medicine.
Coricidin D Cold, flu and sinus tablets.
Dimetapp DM, Dimetapp Elixer.
Contac Day/Night Allergy & Sinus.
All Triaminic products.
Anyone with older forms of these medications or any decongestants should check the labels and discard them if they contain phenylpropanolamine.
It should be noted that the incidence of strokes tended to occur in people who took diet suppressants containing PPA rather than decongestants containing this ingredient. In all cases, serious events remained very rare. In addition, PPA has been used in dozens of medications for more than 50 years. Extreme concern is therefore not warranted.
Antihistamines and decongestants in combination
There are many prescription and over-the-counter products that combine antihistamines and decongestants. A small sample of these over-the-counter combinations includes Allerest, Sudafed Severe Cold Formula, Vicks DayQuil, Claritin-D, Allegra D, Benadryl Allergy/Sinus, Contac Day/Night Allergy & Sinus. They can be effective for all symptoms within 60 minutes, with the congestion going away first. As a general rule, children should not be given combination remedies, which can cause headaches, restlessness and loss of appetite.
HOW ARE ANTIHISTAMINES USED IN ALLERGIC RHINITIS?
Histamine is one of the chemicals released when antibodies overreact to allergens and is the cause of many symptoms of allergic rhinitis. Antihistamines have the following benefits:
They relieve itching, sneezing and runny nose.
They also relieve other allergy symptoms unrelated to rhinitis, including hives and some skin rashes.
Experts recommend that patients take them before an anticipated allergy attack if possible.
There are many antihistamines available, including short- and long-acting forms. They are available as tablets, nasal inhalers, eye drops and syrups. Antihistamines are generally classified as first- and second-generation, depending on whether they contain ingredients that cause more or less sedation.
There are a few caveats to taking any antihistamine, regardless of generation:
Antihistamines can thicken mucus secretions and may actually make bacterial sinusitis worse. People with rhinitis or bacterial sinusitis should not use antihistamines, even during allergy season.
Antihistamines can lose their effectiveness over time and it may be necessary to try a different one.
Ingredients and brand names of first-generation antihistamines. The older, so-called first-generation antihistamines include:
First-generation antihistamines contain compounds called anticholinergics, which tend to produce the side effects that differentiate this group from second-generation antihistamines.
Side effects. Side effects include the following.
Drowsiness and thought disorders. These are serious side effects in adults. There is some evidence that they have a higher risk of workplace and traffic accidents than alcohol, narcotics or prescription sedatives. Interestingly, however, a 2001 study suggests that first-generation antihistamines do not have the same effect on children. In this study, children who took Benedryl did not have more impairment of alertness or learning than children who did not take the antihistamine.
Insomnia or nightmares.
Rapid heartbeat and tightness in the chest (uncommon and should be reported).
Men with an enlarged prostate may have difficulty urinating.
Tips for using first-generation antihistamines. To offset the sedative effect, the following tips may be helpful:
Take the medication at home a few hours before bedtime.
Avoid alcohol and tranquilizers, which increase drowsiness.
Avoid driving or operating heavy machinery.
Note that sedation decreases over time.
Second generation antihistamines
Ingredients and brand names of second-generation antihistamines. The second-generation medications are as follows:
Norethmizole, levocabastine and mizolastine are other unique and promising second-generation antihistamines that are being investigated in the United States and Europe.
The newer second-generation antihistamines do not contain anticholinergics and therefore generally do not cause sedation at recommended doses. In fact, a 2000 study showed that fexofenadine (i.e., Allegra) caused less impairment of driving performance than first-generation diphenhydramine (i.e., Benadryl).
Side effects and precautions.
Common side effects may include headache, dry mouth and nose (these are often only temporary and go away during treatment).
Rapid heartbeat and tightness in the chest (uncommon and should be reported).
Some patients taking Claritin-D 24-hour extended-release tablets have reported upper gastrointestinal tract obstruction, including difficulty swallowing. It is not known whether this is common or typical of all second-generation agents.
Women who are pregnant or breastfeeding should avoid taking these medications unless recommended by a physician. The FDA has approved Claritin for children aged two to five years and Allegra for children aged six to 11 years.
Antihistamine nasal sprays
Azelastine is the first antihistamine available in nasal spray form (Astelin) and, according to one study, is more cost-effective than other seasonal allergy remedies. It can reduce nasal congestion as well as allergy symptoms. In a 2000 study, it reduced nasal congestion and improved sleep in patients with perennial allergic rhinitis, but it did not appear to improve congestion or daytime sleepiness. Disadvantages include a bitter taste, drowsiness and cost.
Problems with previous second-generation antihistamines
Two earlier second-generation drugs, terfenadine (Seldane) and astemizole (Hismanal), have, in rare cases, caused dangerous heart rhythm abnormalities, especially at high doses or in people with liver disease or taking certain other medications. Seldane and Hismanal have been withdrawn from the market. Allegra, Zyrtec and Claritin do not appear to pose the same dangers as Seldane. However, anyone taking a second-generation antihistamine should probably avoid or cautiously use combinations with drugs that have caused problems with Seldane and Hismanal. These drugs include the following:
The antibiotics clarithromycin (Biaxin) and troleandomycin.
Some HIV protease inhibitors.
Serotonin reuptake inhibitor antidepressants (e.g., Prozac, Paxil and Serzone).
Asthma medications, leukotriene antagonists, such as zileuton (Zyflo).
WHEN ARE CORTICOSTEROIDS AND OTHER ANTI-INFLAMMATORY MEDICATIONS USED FOR ALLERGIC RHINITIS?
A number of agents are available to reduce the inflammatory response in allergy and thus prevent an attack in the first place.
Corticosteroid nasal sprays
Benefits of corticosteroid nasal sprays. The most important anti-inflammatory agents are corticosteroids, also called glucocorticoids or, more commonly, steroids. Steroid nasal sprays are safe and have the following benefits:
They reduce inflammation and mucus production and are the most effective agents for relieving symptoms of allergic rhinitis.
They can improve nighttime sleep and daytime alertness in patients with perennial allergic rhinitis.
They can also be helpful in treating polyps.
Some experts even recommend that patients now use a steroid nasal spray as their primary treatment for allergic rhinitis and an antihistamine if the steroid spray is not effective. These medications are generally not useful for non-allergic rhinitis. Corticosteroids do not provide immediate relief of symptoms but may take several hours to take effect.
Nasal spray brands. Corticosteroids available in nasal spray form include:
Beclomethasone (Beconase, Vancenase).
Triamcinolone acetonide (Nasacort, Tri-Nasal).
Budesonide (Rhinocort). Rhinocort Aqua is approved for children over six years of age and requires only one daily dose.
Mometasone Furoate (Nasonex). Approved for use in patients as young as three years of age.
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 the risk of widespread side effects is very low unless the medication is used excessively.
Headache and nosebleeds. These side effects are rare but should be reported to your doctor immediately.
Effect on growth. The main concern for children is whether these medications will have a negative effect on growth. Two large studies done in 2000, which confirm previous studies, report a slight early effect on growth (about half an inch), which also appears to be temporary. It is not yet known, however, whether inhaled steroids have an effect on lung growth in very young children.
Effect on the eyes. Of concern is the possible risk of adverse effects on the eyes, particularly glaucoma, which is a known side effect of oral steroids. Some ophthalmologists have observed increased pressure in the eye (a sign of glaucoma) in some patients taking steroid nasal sprays. (Studies have not found an increased risk of cataracts in young people taking intranasal steroids.) All of these conditions resolve after the steroid is stopped, although periodic eye examinations are advised.
Use during pregnancy. These agents are most likely safe during pregnancy, but pregnant women should carefully discuss all options before taking them.
Nasal passage injury. Steroid sprays can injure the nasal septum (the bony area that separates the nasal passage) if the spray is directed at it. This complication is very rare.
Reduced resistance to infection. People who have an infectious disease or injury to the nose should not take these medications until the disease or injury has been treated and healed. People who have not been vaccinated should avoid steroids (note: vaccines can cause irreversible brain and body damage, and the risks far outweigh the benefits. See SPECIAL REPORTS on vaccines. Please review all evidence about vaccines before deciding to vaccinate yourself or your children) or who have had chickenpox or measles.
Cromolyn is both an anti-inflammatory and an allergen-specific blocking agent. The standard cromolyn nasal spray (Nasalcrom) is not as effective as steroid nasal sprays but it is effective for many people with mild allergies. It is one of the preferred first-line treatments for pregnant women with mild allergic rhinitis. It can take up to three weeks for a person to feel the full benefit.
Side effects. Cromolyn has no major side effects, but minor effects include nasal congestion, coughing, sneezing, wheezing, nausea, nosebleeds and dry throat. The spray may cause burning or irritation.
Leukotriene antagonists are oral medications that block leukotrienes, powerful immune system factors that play an important role in airway constriction and mucus production in allergic asthma. These agents are currently used in the treatment of asthma. However, several studies have reported that montelukast (Singular) significantly reduces hay fever symptoms in children. A 2000 study also showed that zafirlukast (Accolate) helps relieve nasal symptoms of cat allergies. More research is needed.
WHAT IS IMMUNOTHERAPY (ALLERGY SHOTS)?
Benefits of immunotherapy
Immunotherapy (allergy shots) is a very effective treatment for patients with allergies. It is based on the principle that people who receive injections of a specific allergen lose their sensitivity to it. The most common allergens for which injections are given are house dust, cat dander, grass pollen and molds.
Immunotherapy has many advantages:
It targets the specific allergen.
It can reduce sensitivity in the airways of the lungs as well as in the upper respiratory tract.
It can help prevent the development of new allergies in children.
It can help prevent the development of asthma in allergic children.
Candidates for immunotherapy. Immunotherapy (allergy shots) can be given to anyone over the age of seven whose allergies are severe and do not respond to medication. At an international conference in 2000, many experts agreed that immunotherapy should be considered as early as possible for children with asthma and allergies. Immunotherapy is safe for pregnant women with allergies, although the dose should not be increased during pregnancy.
People at risk for complications. People who should probably avoid immunotherapy include the following:
People who have an extreme response to skin tests. This may be a sign of an allergic reaction.
People who are actively wheezing.
Patients with severe uncontrolled asthma or lung disease.
Patients taking certain medications (such as beta-blockers).
The medical condition of any person should be determined before starting treatment.
Administration of the treatment
The main drawback of immunotherapy is that it requires a prolonged course of weekly injections. The process is as follows:
Injections of diluted extracts of the allergen are given at regular intervals, usually twice a week at first, and then in increasing doses until a maintenance dose is reached.
At that point, the intervals between injections may be two to four weeks, and treatment is continued for up to three to five years.
It usually takes several months and may take up to three years to reach a maintenance dose.
Patients may experience some relief within three to six months; if there is no benefit within 12 to 18 months, the injections should be discontinued.
After immunotherapy is stopped, about one-third of allergy sufferers are symptom-free, one-third have improved symptoms and one-third relapse completely.
Side effects and complications of immunotherapy
Ragweed injections, and possibly excessive doses of dust mites, carry a higher risk of side effects than other allergy injections. If complications or allergic reactions develop, they usually occur within 20 minutes, although some can develop up to two hours after the injection.
Side effects of immunotherapy include
General itching, swelling, red eyes, hives, pain at the injection site.
Rarely, a drop in blood pressure, exacerbation of asthma or difficulty breathing. This is due to an extreme hypersensitivity reaction called anaphylaxis. This can also occur if excessive doses are given.
In rare cases, especially with excessive doses or if a patient has a serious lung condition, severe, potentially life-threatening reactions can occur.
Premedication of patients with antihistamines and corticosteroids may help reduce the risk of reactions to immunotherapy, although this may mask early warning signs. This option should be used only after discussion with the physician.
It should be noted that in a 10-year study, the incidence of any adverse event was less than two-tenths of one percent, and the vast majority of events were mild. The risk of a fatal reaction is estimated at one per 63 million injections. (By comparison, the risk of a fatal reaction to penicillin is much higher, at one per 7.5 million injections.)
Investigative Methods to Improve Patient Compliance
The use of a series of injections is effective, but patients often do not adhere to the treatment regimens. Alternative schedules and methods of administration are being investigated that may make the program easier and less burdensome.
Rapid immunotherapy. Researchers are studying so-called "rush" immunotherapy, in which patients get the full maintenance dose by taking several injections a day over a period of three to five days. Rush immunotherapy uses modifications that reduce the risk of severe reactions to excessive doses. Studies suggest that it is effective and safe, with few side effects other than itching. However, patients should be closely monitored during this time to avoid serious reactions.
Oral forms. Trials are underway to test a method that uses an oral gelcap to deliver hay fever immunotherapy. (Previously, taking a pill was not an option because digestive enzymes in the gut made the therapy useless.) Small studies are promising, but larger studies are needed to determine the safety and effectiveness of this method.
Vaccines. Of particular interest is the development of vaccines that make the immune system insensitive to allergens. One such vaccine uses a small protein of the allergen, which is injected into the patient. Other vaccines under study are those that use the genetic material of the allergen (its DNA) to promote tolerance to the allergen.
HOW CAN ALLERGIC RHINITIS BE PREVENTED?
The main irritants or allergens that should be avoided are:
Dust mites, specifically dust mite droppings, which are coated with enzymes containing a potent allergen. (In one study, dust mite allergies did not appear to affect hospitalization, although they are capable of triggering asthma attacks.)
Dander (skin flakes) and animal hair, especially from cats, house mice and dogs. Cats pose the greatest risk of all common pets. House mice have been shown to be important sources of allergens, especially for urban children.
Cockroaches are major asthma triggers and can reduce lung function even in people with no history of asthma.
Studies that report no change in asthma symptoms after control of cat or dust mite allergens are concerning. More research is needed to identify the reasons for this phenomenon.
If families of allergic children, especially if they have asthma, choose to keep pets, the following precautions may be helpful in reducing the risk:
Pets should be kept outside or, if this is not possible, confined to carpet-free areas outside the bedroom.
Cigarette smoke and damp houses increase the risk of allergy reactions in cats.
Washing cats and dogs once a week can reduce allergens. There are dry shampoos, such as Allerpet, for cats and dogs that remove allergens from the skin and fur and are easier to administer than wet shampoos.
It should be noted that cat allergens can be carried on clothing.
For young children, stuffed animals can serve as a comforting substitute, although they may harbor dust mites. Putting stuffed animals in the freezer for 24 hours before washing them kills the mites. For best effect, this process should be done weekly.
Air filters and vacuum cleaners
Air purifiers, Air conditioner filters and vacuum cleaners with HEPA filters can help remove indoor particles and small allergens. Air cleaners have little or no effect on cat allergens or dust mite droppings that lodge in carpets and bedding. HEPA vacuums appear to be effective in reducing second-hand smoke levels and preventing cat allergens from being released into the air. Neither vacuuming nor the use of a carpet dust mite shampoo is effective in removing dust mites; in fact, vacuuming wakes them up. It is best to avoid carpets if possible. Studies that report no change in asthma symptoms after control of cat or dust mite allergens are concerning. More research is needed to determine the reasons for this.
Bedding and curtains
Using semi-permeable covers to completely encase mattresses and pillows is the most effective step in reducing dust mite levels. (Vinyl mattress covers restrict airflow and can also exacerbate or even cause asthma in children. Synthetic pillows may have a significantly higher risk of severe asthma attacks in children than feather or featherless pillows.) Curtains should be replaced with blinds or shades and bedding should be washed using the highest temperature setting. A 1999 study found that children sleeping in lower bunk beds are significantly more likely to develop asthma than their siblings in upper beds. Families with asthmatic children should avoid bunk beds or make sure that asthmatic children sleep in the top bunk. Even with standard beds, it may be helpful to have them sleep as high off the floor as possible.
A 1999 study reported lung irritation in mice exposed to chemical emissions from several brands of disposable diapers. The researchers in this study recommend that children with asthma or other respiratory diseases use cloth diapers and avoid disposable diapers until further research is conducted.
Cockroach and Mouse Extermination
Cockroaches should be eliminated by professional exterminators, although one study reported that ridding a home of cockroaches and cleaning it using standard cleaning techniques did not eliminate the cockroach allergens themselves. Mice must be eliminated, and attempts should be made to remove all dust, which may contain mouse urine and dander.
Camping and hiking trips should not be scheduled during periods of high pollen counts (in northern states, May and June for grass pollen and mid-August through October for ragweed). Patients should avoid strenuous activity when ozone levels are highest, which is usually in the early afternoon, especially on hot, hazy summer days. Levels are lowest in the early morning and at dusk. Patients who are allergic to mold should avoid barns, hay, raking leaves and mowing grass. Exposure to car exhaust can make asthma worse. Fungus in car air conditioners can also be a problem.
Other recommendations for the home
Reducing indoor humidity can decrease dust mite populations. Permanent humidifiers may therefore be counterproductive, because dust mites thrive in humidity, and because they can develop mold if not cleaned daily with a vinegar solution; humidity levels should not exceed 40%. Asthma patients should choose electric ovens over gas ovens, which release nitrogen dioxide, a substance that can worsen asthma symptoms.