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Eustachian Tube Dysfunction and Allergies

The Eustachian tube is a small tubular passageway that connects the middle ear with the junction of the back of the nose and upper throat. It is approximately 1.5 inches long and 3 mm. (0.12 inches) in diameter. It is the structure in the ear that pops when one goes to high altitudes or descends deep in the water. The tube helps to regulate pressure in the middle ear, shield the ear from hearing its own body noises, and drain fluid from the middle ear. The Eustachian tube has a valve that opens and closes. If the tube stays open too much, one may get a constant feeling of increased pressure in one’s ear. In addition, one may hear their own body noises such as hearing one’s voice too loudly or hearing one’s own breathing. On the other hand, if the Eustachian tube stays closed, there may be a buildup of fluid which may result in a feeling of increased pressure and/or pain in the ear as well as a decrease in hearing.

Eustachian tube dysfunction occurs when the tube fails to open and gets stuck closed during swallowing or yawning. This results in a difference in the air pressure between the inside and outside of the middle ear.

The most common cause of Eustachian tube dysfunction is an upper respiratory infection (URI) such as the common cold, flu, or a sinus infection. Other causes of Eustachian tube dysfunction may include allergies (i.e., allergic rhinitis), enlarged tonsils/adenoids, nasal polyps, cigarette smoke, pollution, nasal tumors, cleft palate, and/or tumor at base of the skull. Note that the last 3 causes mentioned are fairly rare causes of Eustachian tube dysfunction.

We will focus on allergies as a cause for Eustachian tube dysfunction. Allergic rhinitis (i.e., hay fever) is a very common condition and accounts for a fair amount of Eustachian tube dysfunction. The classic symptoms of allergic rhinitis may include runny nose, nasal congestion, sneezing, post-nasal drip, snoring, itchy eyes, watery eyes, redness of the eyes, sinus pain/pressure, itchy nose, and itchy throat. As a result of a post-nasal drip, some individuals may experience hoarseness and a sore throat. Others may develop asthma symptoms such as chest tightness, coughing, wheezing, and/or shortness of breath.

Still others, however, may develop symptoms of Eustachian tube dysfunction. These symptoms may include clogged ears, hearing loss, increased ear pressure/pain, popping of the ears, vertigo/dizziness, and/or ringing of the ears (i.e., tinnitus). Allergies may cause a narrowing of the Eustachian tube opening or its passageway resulting in the symptoms described above.

The diagnosis of an allergic cause of Eustachian tube dysfunction begins with a comprehensive history and physical examination. If an allergy is suspected, allergy skin testing or blood tests may be performed. A CT scan of the sinuses may be ordered for individuals who present with recurrent or chronic sinus infections.

The management of the underlying allergies in patients with allergy-induced Eustachian tube dysfunction is the goal of treatment. Treating the underlying allergy may help to reduce the swelling in the lining of the Eustachian tube. Nasal corticosteroids are often effective in reducing the symptoms of Eustachian tube dysfunction. Oral or nasal decongestants may also be beneficial. Oral and nasal antihistamines have also proven beneficial in the treatment of allergic rhinitis. Allergy immunotherapy (i.e., allergy shots, allergy injections, allergy desensitization, allergy hyposensitization) is a very effective tool to treat allergic rhinitis as it works in 80-85% of patients on this therapy.

The board certified allergy doctors at Black & Kletz Allergy have been treating Eustachian tube dysfunction as well as allergies, sinus problems, and asthma. We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. We have been serving the Washington, DC, Northern Virginia, and Maryland metropolitan area for over 50 years and treat both adult and pediatric patients. All 3 offices at Black & Kletz Allergy offer on-site parking and the Washington, DC and McLean, VA offices are Metro accessible. There is a free shuttle that runs between our McLean, VA office and the Spring Hill metro station on the silver line. If you are concerned that you may have Eustachian tube dysfunction, allergies, sinus problems, asthma, hives, eczema (atopic dermatitis), or immune system problems, please call us to schedule an appointment. You may also click Request an Appointment and we will reply within 24 hours by the next business day. At Black & Kletz Allergy, we strive to improve the quality of life in allergic individuals in a professional and compassionate setting.

Seasonal Flu and Asthma

Viruses cause a variety of illnesses in humans ranging from mild upper respiratory infections (URIs) to life-threatening pulmonary and extra-pulmonary diseases. Rhinoviruses, adenoviruses, respiratory syncytial virus (RSV), coronaviruses, and influenza viruses are the most common viruses infecting the respiratory tract. Among these rhinoviruses, RSV, and influenza viruses are common causes of wheezing in children. Recurrent infections with these viruses may play a role in the development of asthma.

Patients with asthma are more susceptible to contracting infections with the influenza virus. In addition, they are also more likely to develop serious complications from influenza. In fact, more than 75% of acute flare-ups of asthma are triggered by infections from influenza, RSV, or rhinovirus.

Infections typically occur in the United States between October and November with a peak infection rate between January and March. There are 3 strains of influenza viruses that cause human infections; influenza A, influenza B and influenza C.

Influenza A and B are typically associated with seasonal disease but also have been associated with several pandemics during the 20th century. For example, in 1918, the Spanish influenza (i.e., Spanish flu), a strain of H1N1 of influenza A, caused between 50 and 100 million deaths worldwide with a mortality rate of 2.5 to 3%. Most of the deaths occurred in adults between the ages of 20 and 40 years old. In 1957, the Asian influenza or Asian flu of the H2N2 strain of influenza A, caused between 1.5 and 2 million deaths. In 1968, the Hong Kong influenza (i.e., Hong Kong flu), a strain of H3N2 influenza A, caused over 1 million deaths.

Currently circulating influenza A viruses of the H1N1 variety are related to the 2009 H1N1 pandemic that emerged in the Spring of 2009 and caused a flu pandemic.

Influenza infection begins with invasion of the respiratory epithelium by the virus. This site in the respiratory system serves as a place for both viral replication and the resulting host’s immune response. Destruction of normal airway tissue and a pro-inflammatory immune response are the primary causes of symptoms associated with influenza infection.

The immune response of the host causes many of the symptoms associated with a viral respiratory infection and those associated with exacerbations of underlying asthma. Certain individuals seem to be at a higher risk for developing infections in the lower airway (i.e. lungs). For example, age less than 6 months old, second-hand smoke exposure, and genetic factors play a role in increasing the risk of infection. Allergic subjects are also more susceptible to infections due to an impaired immune response.


  • Runny nose, stuffy nose, post-nasal drip
  • Sore throat
  • Cough
  • Fever, chills
  • Achiness
  • Vomiting, diarrhea
  • Fatigue


  • Pneumonia
  • Exacerbation of asthma symptoms
  • Inflammation of the heart muscle
  • Inflammation of the brain


Most cases of influenza are mild and symptoms usually resolve within 7 to 10 days. Symptomatic relief can be given by over-the-counter medications such as Tylenol (i.e., acetaminophen) in order to reduce fevers, chills and/or achiness. Inhaled medications such as albuterol (i.e., ProAir, Ventolin) are given to help relieve asthma-like symptoms which may include wheezing, chest tightness, coughing and/or shortness of breath. Rest and increased oral fluids may hasten the recovery process.

The indications for antiviral medications include patients that are at high risk of influenza-related complications including pregnant women, adults over 65 years of age, immunocompromised individuals, and those with chronic medical conditions such as asthma, chronic obstructive pulmonary disease (COPD), and diabetes. Antiviral medications should be used if an individual requires hospitalization, during severe or complicated infection, and during pregnancy. Many primary care physicians recommend antiviral therapy for other scenarios and individuals should check with their physician to see what they recommend.

Antiviral treatment works the best when begun soon after flu-like symptoms begin.  When treatment is started within 2 days of developing flu-like symptoms, antiviral drugs can reduce fever and flu symptoms and shorten the duration of the illness.  They also may decrease the risk of complications such as ear infections in children, respiratory complications requiring antibiotics, and hospitalizations in adults. Some of the antiviral medications used for the treatment of the flu are as follows:

  • Tamiflu (i.e., oseltamivir) is available as a pill or liquid suspension and is FDA approved for the early treatment of the flu in individuals over the age of 2 weeks.
  • Relenza (i.e., zanamivir) is a powder that is inhaled and approved for the early treatment of the flu in individuals 7 years of age and older.  Relenza is administered using an inhaler device and is not recommended for individuals with breathing problems such as asthma or COPD.)
  • Oseltamivir and zanamivir are given twice a day for 5 days.
  • Xofluza (i.e., baloxavir) is a pill given as a single dose by mouth and is approved for early treatment of flu in people 12 years and older.  Xofluza is not recommended for pregnant women, breastfeeding mothers, and outpatients with complicated or progressive illness.
  • Rapivab (i.e., peramivir) is given intravenously by a primary care physician and is approved for the early treatment of flu in individuals 6 months of age and older.


Staying home as much as possible and avoiding contact with others will reduce the risk of acquiring an influenza infection.

Routine annual influenza vaccination (i.e., flu shots) is recommended for all persons 6 months of age and older.  Many types of flu vaccines are licensed by the FDA this year with varying indications based on one’s age group and health status.  Please see the following link for more information.


The board certified allergists at Black & Kletz Allergy treats both adults and children and will gladly answer any questions you have concerning the flu as well as any allergy/immunology topic. Black & Kletz Allergy has 3 offices in the Washington, DC, northern Virginia, and Maryland metropolitan area with locations in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. We offer on-site parking at each location and our Washington, DC and McLean offices are also Metro accessible. There is a free shuttle that runs between our McLean office and the Spring Hill metro station on the silver line. If you would like to make an appointment with an allergy specialist, please call us. Alternatively, you can click Request an Appointment and we will respond within 24 hours by the next business day. Black & Kletz Allergy has been providing quality allergy, asthma, sinus, and immunological services to the DC metro area for more than 5 decades

Churg-Strauss Syndrome


Asthma usually coexists with other allergic disorders such as hay fever (i.e., allergic rhinitis) and/or atopic dermatitis (i.e., eczema). Less commonly, asthma is associated with chronic inflammatory/immunological disorders such as Churg-Strauss syndrome.

Churg-Strauss syndrome is characterized by abnormal and excessive accumulation of types of white blood cells called eosinophils in the blood and tissues leading to tissue damage. Any organ can be affected but the lungs and the blood vessels are most commonly affected. Chronic inflammation of the blood vessels is termed vasculitis or angiitis. Accumulation of eosinophils in tissues may also cause nodular swellings called granulomas. These features give Churg-Strauss syndrome a more descriptive name. Thus Churg-Strauss syndrome is also known as eosinophilic granulomatosis with polyangiitis (EGPA), a type of vasculitis.

The initial clinical manifestations are usually due to from lung involvement resulting in asthma-like symptoms such as coughing, chest tightness, shortness of breath and/or wheezing. These are often followed by generalized systemic symptoms, which take the form of a flu-like illness with fever, fatigue, malaise, loss of appetite, and/or muscle aches (i.e., myalgias).

Vasculitis may cause narrowing of the affected blood vessels, which may result in the blocking or slowing of the flow of blood to various organs and tissues of the body. Inflamed blood vessels may also become thin and fragile, potentially rupturing and bleeding into the surrounding tissues. In addition, the blood vessels may become stretched out causing the development of a bulge in the vessel wall (i.e., aneurysm).

As Churg-Strauss syndrome can affect multiple organ systems, the presentation varies widely from person to person. Involvement of the upper airways is very common, causing rhinitis and chronic or recurrent sinus infections. Excessive tissue growth may result in polyps in the nose and sinuses. Fluid may accumulate in the middle ear causing serous otitis media. Inflammation of the membrane covering the eyeballs is called conjunctivitis and leads to itchy, red eyes and occasionally blurry vision.

Approximately 75% of patients experience nervous system involvement. The neurological symptoms may include chronic pain, the feeling of tingling and numbness, muscle weakness, and/or loss of motor function resulting in paralysis. Blood clots in the blood vessels of the brain and/or bleeding may cause strokes. Gastrointestinal involvement may result in abdominal pain, nausea, vomiting, diarrhea, blood in the stools, and/or inflammation of the membrane lining the large intestine.

Skin lesions develop in about half the patients with Churg-Strauss syndrome and may include purplish spots due to bleeding into skin (i.e., purpura), hives (i.e., urticaria) and/or nodules. Heart abnormalities are caused by inflammation of the blood vessels and the development of nodular lesions within the heart tissue. Symptoms associated with heart disease may include fatigue, shortness of breath, palpitations, chest pain, and/or fainting (i.e., syncope) episodes. Involvement of kidneys is rare however if involved, it may lead to high blood pressure and/or renal failure.


The exact cause of Churg-Strauss syndrome is not clearly established. Most researchers believe that several different factors such as genetic, environmental, and immunological abnormalities may play a role in the development of the disorder. It is classified as an autoimmune disorder. Autoimmune disorders are caused when the body’s natural defenses against “foreign” or invading organisms begin to attack healthy tissue for unknown reasons.

The disorder can affect individuals of almost any age and but generally ranges from 15 to 70 years of age. The incidence in males is slightly higher than in females. It is more commonly seen in families who also have history of other allergic disorders.


An individual is classified as having Churg-Strauss syndrome if 4 of the following 6 findings are identified:

  • Asthma
  • Fleeting lung infiltrates consistent with imitating pneumonia on chest X-rays or CT scans
  • Neuropathy – Nerve damage
  • Abnormality of the sinuses – Recurrent or chronic sinus infections is common
  • Eosinophilia – Defined as greater than 10% eosinophils in the circulating blood
  • Eosinophils outside the blood vessels such as in tissues and organs

In approximately 50% of the patients, blood tests reveal the presence of a specific type of proteins called antineutrophil cytoplasmic antibodies (ANCA). Chest X-rays, sinus X-rays, CT scans and/or tissue biopsies may be needed to confirm the diagnosis.


Initial treatment may include oral or injectable corticosteroids (e.g., prednisone) in order to control excessive inflammation in the blood vessels and other tissues. High doses of corticosteroids are usually used in the beginning with a gradual taper to minimize the risk of side effects. Side effects of corticosteroids may include elevated blood sugars, weight gain, bone problems due to bone loss, cataracts, ulcers of the stomach, depression, and an increase in infections.

Patients who do not respond to corticosteroid medications may need immunosuppressive and/or cytotoxic medications (e.g., methotrexate, cyclophosphamide). Some patients may need monthly infusions of immunoglobulins either intravenously or under the skin (subcutaneously).
In 2017, Nucala (mepolizumab) was approved by the U.S. Food and Drug Administration (FDA) to treat adult patients with Churg-Strauss syndrome. It is a biologic medication that is injected under the skin every 4 weeks. It works by blocking a cytokine called IL-5 (i.e., interleukin-5) which is needed for growth and differentiation of eosinophils. In 2018, the FDA granted orphan drug designation ODD for Fasenra (benralizumab), another biologic medication used to treat Churg-Strauss syndrome.

Early initiation of treatments as soon as the diagnosis is made, can help prevent tissue damage and long-term complications.

The board certified allergists at Black & Kletz Allergy have 3 offices in the Washington, DC, Northern Virginia, and Maryland metropolitan area and treat both adults and children with asthma, Churg-Straus syndrome, sinus disease, hay fever (i.e., allergic rhinitis), nasal polyps, other allergic and immunologic disorders. We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. Black & Kletz Allergy offers on-site parking at each of their 3 convenient office locations and the Washington, DC and McLean, VA offices are also Metro accessible. There is a free shuttle that runs between our McLean, VA office and the Spring Hill metro station on the silver line. To make an appointment, please call any of our offices or you can click Request an Appointment and we will respond within 24 hours on the next business day. Black & Kletz Allergy has been serving the asthma and allergy needs of the Washington, DC metropolitan area for more than 50 years. We strive to provide high quality allergy and asthma care in a caring professional environment.

Oak Mites

If you have been doing yardwork this Summer, you may have noticed a multitude of red swollen itchy hive-like marks that seem like some sort of bug bite all over your body. You may be correct and these bug bites may well be caused by oak mites. Other names for oak mites include oak leaf gall mites, oak tree mites, and itch mites. Oak mites probably originated in Europe but have been in North America since the early 2000’s. They have increased in frequency in the U.S. ever since. They tend to be more of a nuisance in the Summer and Fall. Oak mites are microscopic and contain 8 legs. Since they have 8 legs, they are considered arachnids, like a spider or a tick. They are technically not insects because insects have 6 legs.

Normally, oak mites tend to hide in oak galls. Oak galls are unusual deformities (i.e., swellings) of plant growth comprised of plant tissue commonly on foliage caused by chemicals that regulate plant growth which are produced by insects or arthropods. Oak mites usually feed on midge fly larvae in these oak galls. This year, however, oak mites have also feasted on cicada eggs. The oak mites fall out of oak trees while eating cicada eggs, land on humans, and then bite them. Keep in mind that oak mites can fall out of trees in very large numbers, sometimes more than hundreds of thousands at a time. Oak mites are also carried off by the wind and can spread to other trees in this manner.

As mentioned above, this year in particular, the number of oak mites have increased almost exponentially in certain areas of the U.S. including the Washington DC, Maryland, and Virginia region. This Summer brought the reemergence of the 17-year Brood X cicadas, and as a result, oak mites have come out in full force in the Washington, DC metropolitan area in hopes to thrive on the plentiful cicada eggs. The good news is that once that food source (i.e., cicada eggs) is gone, the numbers of oak mites will diminish greatly.

Since oak mites are microscopic and cannot be seen with the naked eye, the bites are even more frustrating since they appear on the skin almost like magic. The bites can be numerous and overwhelming. In addition to biting exposed skin (e.g., arms, neck, face), oak mites can bite under loose clothing and/or between the hairs on the head.

You may wonder what you can do in order to avoid oak mite bites. Some avoidance measures may include the following:

  • Avoid congregating under trees, especially in the Summer and Fall
  • Wear protective clothing including hat and gloves when in the woods or under a tree
  • Wash clothes and put dryer on medium temperature after being near trees
  • Keep house doors and windows closed
  • Shower after being outside near trees

The treatment of oak mite bites is pretty basic and involves some common sense remedies. The use of over-the-counter antihistamines (e.g., Benadryl, Claritin, Allegra, Zyrtec) may be beneficial to help with associated itching and swelling. Over-the-counter Hydrocortisone creams may also help the itching as well as reduce the size and duration of the hive-like reactions from the bites. It may also be advantageous to apply a cold compress to the oak mite bites to help prevent swelling, if possible.

The board certified allergy doctors at Black & Kletz Allergy treats both adults and children and will gladly answer any questions you have concerning oak mite and insect bites. Black & Kletz Allergy has 3 offices in the Washington, DC, northern Virginia, and Maryland metropolitan area with locations in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. We offer on-site parking at each location and the Washington, DC and McLean offices are also Metro accessible. There is a free shuttle that runs between our McLean office and the Spring Hill metro station on the silver line. If you would like to make an appointment with our allergy specialist, please call us or alternatively, you can click Request an Appointment and we will respond within 24 hours by the next business day. Black & Kletz Allergy has been providing quality allergy, asthma, sinus, and immunological services to the Washington, DC metro area for more than 50 years.

Common Variable Immunodeficiency

Our immune system defends us against microorganisms that cause infections. It also protects us from certain cancers. Thus when the immune system functions sub-optimally, we are more susceptible to infections and cancers.

Common variable immunodeficiency (CVID) is one of the most common conditions where the immune system is deficient or less functional.


It is thought that genetic defects are most likely the underlying cause for this condition, although specific gene defects were identified in only 10% of the cases. Common variable immunodeficiency is known to occur more commonly in certain families which also suggests a genetic cause.
Males and females are equally affected in CVID. Common variable immunodeficiency occurs in approximately 1 out of every 25,000 individuals. Even though the condition is present from early childhood, it is most commonly diagnosed in the second or third decades of life.


The most common presentation of CVID involves recurrent infections involving various organ systems. The infections are typically as specified below:

  • Upper respiratory and/or sinus infections
  • Ear and/or throat infections
  • Bronchitis and/or pneumonia
  • Gastrointestinal infections
  • Neurological infections
  • Fatigue, joint pains (i.e., arthralgias), and/or muscle pains (i.e., myalgias)

The infections can vary in severity from mild to severe. Many patients require emergency room visits and/or hospitalizations for the management of severe infections.

Physical examination sometimes reveals enlarged lymph nodes and rarely skin rashes.


The diagnosis of common variable immunodeficiency is initially suspected on the basis of a history of recurrent infections for a number of years, often with unusual or rare organisms.

Confirmation of the diagnosis is completed by blood tests which reveal lower numbers of lymphocytes and antibodies (i.e., proteins that fight infections) compared to normal reference levels. Measuring antibody levels before and after vaccinations is also helpful in testing the ability of the immune system to manufacture specific antibodies. It should be noted that CVID patients cannot respond to immunizations adequately and thus do not mount a good immune response to vaccinations.


  • Antibiotic treatment for infections: Patients need prolonged courses of antibiotics in order to adequately treat severe bacterial infections.
  • Prophylactic antibiotics: Patients require prophylactic antibiotics in order to prevent infections prior to surgical and/or dental procedures.
  • Antibody supplementation: Most patients need regular infusions of antibodies, which are pooled from donors, either through a vein (i.e., intravenous) or under the skin (i.e., subcutaneous) on a regular basis. This treatment maintains the integrity of the immune system and helps prevent frequent and repeated infections. This treatment, known as gamma globulin therapy (i.e., immunoglobulin therapy, antibody replacement therapy), needs to be continued lifelong, as there is no cure for common variable immunodeficiency.


Patients with CVID are more likely to develop autoimmune disorders affecting the thyroid gland, liver, and connective tissues. Autoimmune conditions may also attack blood cells resulting in anemia and/or low platelet counts. Low platelet counts usually manifests itself as easy bruisability and/or increased bleeding.

Individuals with common variable immunodeficiency are also more susceptible for certain types of cancers and granulomas (i.e., inflammatory swellings) in the skin, lymph nodes, stomach, and/or liver. For this reason, patients need regular monitoring, surveillance, and screening for these type of cancers. It is recommended that all individuals with this disorder follow up with their primary care physician on a routine basis in order to be diligent in this regard.


With regular antibody replacement therapy, prophylactic and curative antibiotic regimens, and close monitoring for complications, most individuals with CVID can lead long and fulfilling lives.

The board certified allergy doctors at Black & Kletz Allergy have 3 convenient office locations in the Washington, DC, Northern Virginia, and Maryland metropolitan area and are very experienced in the diagnosis and treatment of immunodeficiency disorders such as common variable immunodeficiency. Black & Kletz Allergy treat both adults and children and have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. We offer on-site parking at each location and the Washington, DC and McLean, VA offices are Metro accessible. There is a free shuttle that runs between the McLean, VA office and the Spring Hill metro station on the silver line. Please call our office to make an appointment or alternatively, you can click Request an Appointment and we will respond within 24 hours by the next business day. The allergy specialists at Black & Kletz Allergy have been serving the Washington, DC metropolitan area for more than 5 decades. We pride ourselves in providing excellent immunological care as well as exceptional allergy and asthma care in a professional and friendly setting.

Reactions to Food Additives

The food we consume everyday contains many natural and artificial additives. Most of these additives to food are chemicals and biological substances. In most of the cases, they are usually either preservatives or coloring substances.

Though additives have been used for hundreds of years, there has been an increase in the number and variety of substances added to food in the past few decades. The Food and Drug Administration (FDA) lists more than 4,000 different additives on their Food Additive and Color Additive lists.

Some of us can be “intolerant” to food additives, however, food additives may cause both immediate (i.e., symptoms beginning within a few minutes of eating food) and/or delayed (i.e., symptoms beginning several hours after eating food) hypersensitivity reactions. Immediate reactions are mediated by an antibody called IgE and delayed reactions are usually caused by T-lymphocytes (i.e., T-cells). The exact mechanism of reactivity however, may be unknown in a number of reactions caused by the additives.

Two common additives found in food in the U.S. that need special mention include sulfites and food dyes.


Sulfites are one of the most commonly used preservatives for foods. They reduce spoilage and prevent fruit and vegetable browning. They also have some beneficial anti-oxidant properties. Sulfites are present in dried fruits in high quantities. They are also usually added to baked goods, shrimp, and condiments. Sulfites are also present in several varieties of wines and beers.

There are many case reports of sulfites causing hives (i.e., urticaria), angioedema (i.e., soft tissue swellings), and flare-ups of asthma. The FDA now requires that most preservatives, including sulfites, be cleared mentioned in the food labels. Sulfites can appear as alternate verbiage on product labels and can be written as potassium bisulfite, potassium metabisulfite, sodium bisulfite, sodium metabisulfite, or sodium sulfite.

Sulfite, sulfa, sulfate, and sulfur are 4 terms that sound very similar but are very different when it comes down to their allergy profile. Sulfa drugs contain the sulfonamide molecule and are typically broken down to sulfonamide antimicrobials (i.e., antibiotics) and sulfonamide non-microbials. The chemical structures are different between the sulfonamide antimicrobials and the sulfonamide non-microbials and thus individuals who have allergic reactions to one group should not have allergic reactions to the other group of sulfonamides. It should be noted that approximately 3% of individuals are allergic or have adverse effects from sulfonamide antimicrobials. The sulfonamide antibiotics may include sulfamethoxazole (i.e., Bactrim, Septra), sulfafurazole, sulfisoxazole (i.e., Pediazole), and sulfadiazine. The non-microbial sulfonamides may include Celebrex (i.e., celecoxib), Lasix (i.e., furosemide), Microzide (i.e., hydrochlorothiazide), Imitrex (i.e., sumatriptan), Amaryl (i.e., glimepiride), and Diabeta (i.e., Glyburide).

Sulfates are present in many medications (i.e., magnesium sulfate, ferrous sulfate), supplements (i.e., glucosamine sulfate), and personal care products (toothpaste, shaving foam, shampoo). Sulfates are different chemically from sulfites and sulfa drugs and are unlikely to cause allergic reactions.

Sulfur is a chemical element and omnipresent. It is thus practically impossible to have an allergy to sulfur.

Food Dyes:

Carmine is a coloring agent present in red-colored foods. It is extracted from the insect known as the cochineal. It is known as “cochineal extract” or “natural red 4.” It has been shown to cause facial swelling, rashes, wheezing, and/or anaphylaxis.

Saffron, annatto, and yellow dye # 5 are added to foods to color them yellow. Saffron is a spice that has been around for thousands of years. It can be toxic in larger quantities. An allergy to saffron is known to cause itching, skin irritation, rashes, redness of the skin, and hives. Annato comes from the seeds of the achiote tree and can be found in some cereals, drinks, cheeses, and snack foods. It has been shown to cause rashes and anaphylaxis is some individuals. Yellow dye # 5 (i.e., tartrazine) is known to cause hives and angioedema is selected individuals. It is also known to trigger asthma in some individuals.

It is important to note that any food dye may cause allergic reactions in susceptible individuals. Although food dye allergies are not too common, it is important to be aware that reactions such as itchy skin, redness of the skin, hives, angioedema, and anaphylaxis may occur.


If one experiences untoward reactions to many different unrelated foods or if reactions occur only after eating commercially packaged foods, sensitivity to the additives should be suspected. Maintaining a food and symptom diary can be helpful in narrowing down the additive in question by establishing a temporal relationship between exposure and the onset of adverse effects.

Skin prick testing or blood testing are not useful in the diagnosis of food additive sensitivity; however, they may be useful in ruling out specific foods. Oral food challenges are usually helpful in the diagnosis. In this procedure, foods are eaten in small increments at regular intervals, beginning with a tiny quantity, while closely monitoring for adverse reactions under controlled circumstances with standardized protocols to treat an allergic reaction.


Avoidance of the foods containing the suspected or confirmed sensitizing additive is essential in order to prevent untoward reactions. Careful reading of labels before eating is essential in reducing the likelihood of reactions. Enquiring about the specific ingredients of a dish in restaurants will go a long way in preventing untoward symptoms.

Patients with a history of anaphylaxis triggered by either known or unknown substances should always carry a self-injectable epinephrine device (e.g., EpiPen, Auvi-Q, Adrenaclick) at all times. If the device is used, the patient must go immediately to the closest emergency room.

More and more natural and artificial chemicals are being added to our food as preservatives, flavor enhancers, and coloring agents.  The U.S. Food and Drug Administration (FDA) lists close to 4,000 substances as food additives.

Despite widespread use of these chemicals in food, adverse reactions are fortunately uncommon.  Most cases are described in the literature as single case reports or reports of a small cluster of patients.


Sulfites:  These chemicals in the gaseous form can cause lung irritation and may trigger asthma in sensitive asthmatics.  They are commonly found in liquid form in processed cold drinks and fruit juice concentrates in order to extend their shelf lives.  Sulfites are also added to most wines and sprayed onto cut foods in order to keep them fresh and prevent discoloration or browning. They are used to preserve smoked and processed meats, dried fruit (e.g., apricots), and salads.  In its solid form, sulfites can cause hives when ingested.

Benzoic acid (i.e., benzoate) and Parabens:  Benzoates and parabens have antibacterial and anti-fungal properties in order to help with the prevention of food spoilage.  These agents are added to pharmaceutical and food products such as drinks (e.g., sugar-free cola). They occur naturally in prunes, cinnamon, tea, and berries.  These substances may cause urticaria (i.e., hives), asthma and angioedema (i.e., swelling) in sensitive individuals.

Antioxidants:  Synthetic phenolic antioxidants [e.g., BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene)] are typically added to processed foods such as dry cereals and potato flakes in order to prevent the fats and oils in these foods from turning rancid when exposed to air.  Unfortunately these antioxidants may trigger asthma, rhinitis, and urticarial in some sensitive individuals.

Flavor Enhancers:

Aspartame (e.g., NutraSweet, Equal), a low-calorie sweetener, can occasionally trigger itchy hives and swelling of the body.  It is also important to note that individuals with genetic condition phenylketonuria should avoid aspartame. Aspartame breaks down into an essential amino acid called phenyalanine which is toxic to individuals with phenylketonuria since these patients are unable to metabolize phenyalanine.


Azo dyes [e.g., tartrazine (i.e., yellow dye #5)] and Non-azo dyes (e.g., erythrocine) can trigger hives, asthma, and generalized allergic reactions.

Nitrates and Nitrites give meat a pink color to look more attractive.  These food colorings are typically found in bacon, salami, and frankfurters.

Monosodium Glutamate (MSG) may trigger the “Chinese Restaurant Syndrome” which causes individuals to experience headaches as well as burning and/or tightening of the chest, neck, and face.  MSG may be found in soups, pot noodles, and instant drinks, among other foods.

Naturally Occurring Substances:

Vasoactive amines: Natural histamine, serotonin, and tyramine occur in some ripe cheeses, fish, cured sausage, red wine, chocolate, and pickled vegetables and may induce cramping, flushing, headache, and palpitations in a dose-related manner.  Of note, there is a condition known as “scombroid poisoning” which occurs in individuals who eat spoiled fish. In this condition, there are abnormally high quantities of histamine in the fish due to improper storage or processing.  The typical fish affected may include tuna, mackerel, herring, sardine, anchovy, marlin, and bluefish. The symptoms may include flushing, headache, generalized itching, blurred vision, abdominal cramps, and/or diarrhea. Scombroid poisoning is often wrongly diagnosed as a fish allergy since similar symptoms may be associated with a true fish allergy.  One key factor to look for is to see if other individuals eating the same piece of fish exhibited symptoms. If so, it is more likely to be scombroid poisoning due to eating spoiled fish as opposed to a fish allergy.

Caffeine found in foods, medication, tea, coffee, and carbonated beverages induces dose-dependent agitation, palpitations, nausea, and/or tremors.

Salicylates (i.e., aspirin-like naturally occurring chemicals) may induce urticaria, asthma, and/or nasal polyp growth.  They are found in curry powder, paprika, oranges, apricots, ginger, honey, berries, fruit skins, tea, and almonds.  Salicylate sensitive individuals also tend to have adverse reactions to benzoates and tartrazine.


The precise mechanism how food additives cause reactions is not well understood in many instances.  The IgE antibody, which plays a crucial role in immediate-type (i.e., Type I) allergic reactions to food, is usually not involved in adverse reactions caused by food additives.

Skin prick tests and allergy blood tests are not helpful in identifying the food additive culprit in most cases.  Careful observation and maintaining food and symptom diaries are sometimes useful in narrowing down the offending additive. Oral challenges under close monitoring in controlled environments may be needed to arrive at a specific diagnosis.


Avoidance of the suspected food additive is the only certain way of preventing adverse effects.  One should be vigilant about reading food labels and asking restaurants about ingredients and cooking methods.

If there is a history of anaphylaxis, carrying an epinephrine auto-injector (e.g., EpiPen, Auvi-Q, Adrenaclick) is extremely helpful in emergency treatment.  It is important to emphasize that if a self-injectable epinephrine device is used, one should go immediately to the closest emergency room.

The board certified allergy doctors at Black & Kletz Allergy have 3 locations in the Washington, Northern Virginia, and Maryland metropolitan area. We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA. Our 3 office locations have on-site parking and the Washington, DC and McLean, VA offices are Metro accessible. Our McLean office has a free shuttle that runs between our office and the Spring Hill metro station on the silver line. The allergy doctors at Black & Kletz Allergy diagnose and treat both adult and pediatric patients. To schedule an appointment, please call our office directly or alternatively, you can click Request an Appointment and we will respond within 24 hours by the next business day. The allergy doctors at Black & Kletz Allergy have been serving patients with food additive allergies, food allergies, hay fever (i.e., allergic rhinitis), asthma, sinus disease, hives, eczema, insect sting allergies, medication allergies, and immunological disorders for more than 50 years. If you are bothered from allergies, it is our mission to improve your quality of life by reducing or preventing your unwanted and bothersome allergy symptoms.

Pregnancy and Allergies


Asthma and allergies are quite common in pregnancy. Although complications from asthma and allergies are much less common, approximately 1% of pregnant women suffer from asthma during their pregnancy. Many more suffer from allergic rhinitis (i.e., hay fever) and other allergies (e.g., food, medication). Allergy symptoms due to allergies tend to be worse in pregnancy for approximately one-third of women, better in another one-third, and about the same as before pregnancy for the other one-third. It is important to note that it is also possible to develop new allergies during pregnancy.

Many women without a previous history of allergies complain of allergy symptoms during pregnancy. In some of these women, they indeed have developed allergies. In others, the allergy symptoms are present, but there is no definitive allergy. In these latter women, their elevated estrogen and progesterone levels are responsible for the typical nasal congestion that they may be experiencing. The increased hormone levels cause one’s mucus membranes to swell. When this swelling affects the nose, nasal congestion is the result. The diagnosis of hormone-induced nasal congestion of pregnancy is then justified if the hormonal elevation alone is responsible for the nasal congestion. Note that in addition to the nasal congestion, some nonallergic pregnant women who have hormone-induced nasal congestion of pregnancy may also experience a post-nasal drip and an associated cough due to the post-nasal drip.

The most common allergies during pregnancy are not any different than in non-pregnant women. Allergic rhinitis symptoms during pregnancy are still due to the same common allergens which usually include pollens, dust mites, molds, pets (e.g., cats, dogs), and cockroaches. The classic symptoms still may include sneezing, runny nose, itchy nose, nasal congestion, post-nasal drip, itchy throat, sinus congestion, sinus headaches, itchy eyes, watery eyes, puffy eyes, and/or redness of the eyes. In asthmatic individuals, wheezing, chest tightness, coughing, and/or shortness of breath may also occur. It should be emphasized that the lack of sneezing and itching in a pregnant woman with nasal congestion should be a red flag to consider a diagnosis of hormone-induced nasal congestion of pregnancy, as opposed to the classic allergic rhinitis in a pregnant individual.

The diagnosis of allergic rhinitis and/or asthma while pregnant begins with a comprehensive history and physical examination history performed by a board certified allergist, like the ones at Black & Kletz Allergy. Allergy blood tests may be ordered to diagnose a pregnant patient. Allergy skin testing is generally not performed on pregnant women.

Once the diagnosis is made, the focus turns to treatment. Treatment of allergic pregnant women is similar to non-pregnant women however the medications used to treat pregnant women are more limited. Only medications that have a Category B pregnancy rating and occasionally a Category C pregnancy rating (if needed) are generally used. There are antihistamines, nasal sprays, leukotriene antagonists, and asthma inhalers that are Category B which are utilized first in the treatment of allergic rhinitis and asthma. Most of the time, improvement can be obtained by using just Category B pregnancy medications. Pregnant women should be cautious before using any medication while pregnant, particularly during the first trimester. Pregnant women should get approval from their Ob/Gyn physician before using any medication, even if prescribed by another physician.

Allergy immunotherapy (i.e., allergy shots, allergy injections, allergy desensitization, allergy hyposensitization) can be continued in pregnant women. Individuals however are not started on allergy immunotherapy if one is already pregnant.

One other important caveat regarding the treating allergies in both allergic and nonallergic patients is the concept of avoidance. It is always recommended to avoid the offending allergen whether it is in the environment (e.g., pollens, molds, dust mites, pets), in the food (e.g., peanuts, shellfish, nuts, fish), or anywhere else. Avoiding what one is allergic to is always the best alternative if possible.

The board certified allergists at Black & Kletz Allergy have been treating pregnant and lactating women for many years. Black &Kletz Allergy has 3 convenient locations in the Washington, DC, Northern Virginia, and Maryland metropolitan area. We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA which all offer on-site parking. The Washington, DC and McLean, VA locations are Metro assessable. We offer a free shuttle that runs between our McLean, VA office and the Spring Hill metro station on the silver line. Please call us to schedule an appointment or you can click Request an Appointment and we will reply within 24 hours by the next business day. The allergy specialists of Black & Kletz Allergy are eager to help you with your allergy, asthma, and immunology needs. We are dedicated to providing exceptional care and service to you as we have been doing in the Washington, DC metro area for more than 50 years.

Pork-Cat Syndrome

Pork-cat syndrome is a condition in which individuals become allergic to pork following exposure and sensitivity to cats.  It almost always occurs in individuals who have or have had cats.

Typically, if one is sensitized to cat allergen, the allergic symptoms one may develop are generally triggered by exposure to the cat allergen from the air.  These allergic rhinitis (i.e., hay fever) symptoms may include itchy eyes, red eyes, watery eyes, sneezing, nasal congestion, runny nose, post-nasal drip, itchy throat, sinus pressure, and/or sinus headaches.  Cat allergen may also trigger and/or aggravate asthma symptoms in some individuals and cause coughing, wheezing, chest tightness, and/or shortness of breath.  The treatment for classic cat allergies includes avoiding exposure to cats, medications to relieve the symptoms, and/or allergy immunotherapy (i.e., allergy injections, allergy shots, allergy desensitization, allergy hyposensitization).  Medications may include oral antihistamines, oral decongestants, leukotriene antagonists, nasal corticosteroids, nasal antihistamines, nasal anticholinergics, nasal mast cell stabilizers, ocular antihistamines, and/or ocular mast cell stabilizers.  The use of oral corticosteroids, nasal decongestants, ocular corticosteroids, and ocular decongestants are discouraged due to their side effects and/or “addictive” qualities.

What is common between cat and pork allergies?

Cat-allergic individuals are also more likely to develop food allergies, particularly to meat, than that of the general population.  The most common type of food allergy related to a history of a cat allergy is that of an allergic reaction to pork.  The symptoms generally begin within an hour after the ingestion of pork.  The usual symptoms may include generalized itching (i.e., pruritus) and/or breaking out in hives (urticaria).  These symptoms can be followed by abdominal cramping, nausea, and diarrhea.  Rarely, more severe reactions such as a sudden drop in blood pressure or throat swelling, which can cause a difficulty in swallowing or breathing, or life-threatening anaphylaxis may occur.  Needless to say, allergic reactions need to be quickly identified and treated with medications in order to stop them from progressing to anaphylaxis.  As meat allergies cannot be desensitized at this time, sensitized individuals should avoid exposure to meat at all times.

The reason that some cat-sensitized individuals are susceptible to pork allergies is that some individuals are not only allergic to the cat dander, but are also allergic to a protein found in cats called albumin.  Albumin is also found in meat from pigs and other animals.  The albumins share several common amino acid sequences.  This phenomenon is termed cross species cross-reactivity.  When albumin is consumed after eating pork meat, an allergic reaction may occur in some cat-sensitive individuals (i.e., in patients that are allergic to cat albumin).

The diagnosis is suspected when a person with a history of allergies to cat also reacts to pork.  It is confirmed by the demonstration of the presence of specific antibodies to both cat and pork allergens.  This is accomplished by skin prick testing and/or laboratory tests.  Skin tests with raw pork are usually positive but with baked meat can be negative since the heat often denatures the protein.  An oral food challenge to pork may sometimes be needed to establish the diagnosis.

This condition should be distinguished from the more common allergies to mammalian meat caused by antibodies to a carbohydrate called alpha-gal.  This condition, which is known as mammalian meat allergy, usually follows a tick bite which introduces the allergen into humans.  In this condition, the symptoms usually begin several hours after ingestion of mammal meat (e.g., beef, pork, lamb, venison) as a “delayed anaphylaxis.”  The diagnosis is confirmed by the detection of specific IgE antibodies to alpha-gal in a blood test.  Some individuals with this condition will have their sensitivity reduced after several years of avoiding the ingestion of mammalian meat.

The management of pork-cat syndrome entails reducing exposure to cats as well as avoiding of pork at all times.  Some individuals will be able to tolerate well-cooked pork, as high temperatures can denature the offending protein and render it less harmful.  Most patients with this condition also need to carry self-injectable epinephrine for emergency use in case of a severe reaction after the accidental exposure to pork.

The board certified allergy doctors at Black & Kletz Allergy have 3 office locations in the Washington, Northern Virginia, and Maryland metropolitan area.  The allergy specialists at Black & Kletz Allergy treat both pediatric and adult patients.  We have offices in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA.  All 3 of our offices have on-site parking and both the Washington, DC and McLean, VA offices are Metro accessible.  In addition, the McLean, VA office has a complementary shuttle that runs between our office and the Spring Hill metro station on the silver line.   For an appointment, please call our office or alternatively, you can click Request an Appointment and we will respond within 24 hours by the next business day.  The allergists at Black & Kletz Allergy have been helping patients with food allergies, hay fever, asthma, eczema, sinus disease, hives, insect sting allergies, immunological disorders, and medication allergies for over a half a century.  If you suffer from any allergy, whether unusual or not, it is our mission to improve your quality of life by reducing or preventing your unwanted and bothersome allergy symptoms.