Is it Allergy or a Cold?

It’s winter and  the season for runny, stuffy noses, coughing and hacking, and scratchy, sore throats – but not necessarily from allergies.  A question that comes up a lot this time of year is  how to tell the difference between allergies, a sinus infection, and a cold? This is, of course a trick question because a cold IS a sinus infection, technically speaking.  Most cold viruses not only affect the nose and throat but also the sinuses.  What about telling the difference between an allergy attack and an infection?  This can be a challenge at times but there are clues. Typically, allergies cause more itching and rarely pain and mucous is usually clear.  With an upper respiratory infection, drainage can be discolored, the throat can be raw and sore, and you may have a fever.   Also, allergies are not contagious and the fact that 70% of your school or office is home sick with the very same awful symptoms you just came down with might suggest a bug rather than a pollen problem.

This time of year, the primary allergen in the air is pollen from evergreen trees such as Juniper.   So knowing what you are allergic can help us interpret your symptoms.  For example if you are not allergic to Juniper, then respiratory symptoms during the winter are not likely to be allergy related, unless of course your aunt came to visit for christmas and brought her six cats.

You might ask: If it is not an allergy but an infection, then an antibiotic is needed to get better right? Antibiotics are one of the most important discoveries of our modern era.  They have saved millions of lives and turned the nightmare of a devastating infection in a child to a routine affair easily treated by a prescription from the family doctor.  But as miraculous as antibiotics are, they are worthless in the treatment of viral infections, and viral infections are the most common cause of respiratory infection in children and adults.

This however, has not stopped antibiotics from being routinely prescribed for cold viruses.  But how do we know if it is a cold virus and not a bacterial infection and one that would respond to an antibiotic and make me feel better in hours rather than days?  For the most part, a cold causes a lot of uncomfortable symptoms for the first 2-3 days, symptoms plateau around day 4-5, and then slowly improve, usually resolving completely by day 7-10. A cold may lead to a bacterial sinus infection but this rarely occurs in the first week of symptoms. Therefore, the major consensus guidelines for doctors suggest that antibiotics are rarely helpful and not recommended for most patients with typical cases of upper respiratory infection lasting less than 4 weeks.

So how successful are prescribers at following these guidelines? A recent study reported in The Journal of Allergy & Clinical Immunology (JACI),  reviewed the overall national use of antibiotics for adults with sinus infections.  Study data were taken from the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey from 2006-2010, from the U.S. Department of Health and Human Services, and included antibiotic prescriptions associated with outpatient visits made by adults diagnosed with acute or chronic sinusitis. Over the five year study period, sinus infections  accounted for 11% of all primary diagnoses for ambulatory care visits  for which  antibiotics were  prescribed, more than any other diagnosis.  There were 21.4 million estimated visits associated with a primary diagnosis of acute sinus infection, and 47.9 million estimated visits associated with a primary diagnosis of chronic sinus infection.

Antibiotics were prescribed in 86% of acute sinusitis cases, in spite of established clinical practice guidelines recommending against the use of antibiotics for typical acute sinus infections.

No one wants to be sick and when we are ill with a cold we want to get better as soon as possible.  And although the approach: ”better to be safe than sorry and take an antibiotic at the first sign of symptoms rather than wait several weeks to see if it will get better on it’s own” may seem reasonable,  the potential consequences associated with excessive and unjustified use of antibiotics, including allergic reactions, severe adverse side effects, unnecessary costs, and increasing bacterial resistance, cannot be justified.

Both physicians, who want to help and may be afraid to say no, and patients, who may have unrealistic expectations, are to blame for the growing problem of inappropriate antibiotic use.   However, while most of us have grown up in the age of wonder drugs, we are now at risk of entering a new and very scary time called “the post antibiotic era”.    A place were no pill or shot will save us from foes that we have long thought vanquished.

So if you have a cold:  get plenty of rest, avoid public places when possible so that you don’t infect others, and give it time.  If you do not see any improvement in a week or so or if symptoms are getting significantly worse, see your doctor.

Arizona Cough

Cough is one of the most common symptoms prompting patients to see a doctor in the United States with an estimated 30 million trips to the doctor for this problem each year. More than 40% of the patients seen in our allergy and pulmonary practice between November and February complain of cough.

Cough is classified as acute, sub acute or chronic depending on how long the symptom has been present.   Acute cough lasts for less than three weeks and is most commonly the result of an acute respiratory tract infection. Other more serious causes of acute cough include pneumonia and in our clinic in Arizona, coccidiomycosis infection or valley fever.

A cough associated with typical cold symptoms may be called bronchitis, particularly when symptoms last for more than a week. Acute bronchitis is most often caused by a viral infection although other respiratory infections besides viruses, including Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Bordetella pertussis may be involved.  Although most viral infections cause symptoms lasting less than 2-3 weeks, some patients with viral or other upper respiratory tract infections will continue to cough for more than eight weeks after the acute infection.  This persistent cough may be the result of a type of airway injury.  Although the source of the infection is gone, the injury remains and takes time to heal.

Another important cause of acute cough in children in adults is pertussis (whooping cough).  Pertussis is a very contagious disease caused by the bacteria Bordetella pertussis. Before the advent of vaccinations in the 1940s, pertussis was a major cause of severe illness and death among infants and children.  Although cases of pertussis decreased by more than 99% after the introduction of pertussis vaccine, it remains a cause for concern, in part because of the incomplete protection provided by the vaccine and the increasing numbers of children that are never vaccinated.  In fact, pertussis is the only vaccine-preventable disease that is associated with increasing deaths in the United States.  In 2010, more than nine thousand cases of whooping cough were reported in California. At least ten infants died from the infection prompting the health authorities to declare a pertusis epidemic.

Pertusis infection usually begins with symptoms similar to the common cold although after several weeks, frequent and often violent coughing begins. The illness is most severe in infants and young children, particularly in those that have not been immunized. In adults, the only symptoms may be a persistent cough.

In a recent study published in The Journal of Allergy and Clinical Immunology (JACI), the risk of adults and children with asthma developing whooping cough was 1.7 times higher than those without asthma, suggesting that asthma significantly increased risk for whooping cough.

A cough lasting more than 4-6 weeks without a clear history of acute respiratory infection is considered chronic and is most likely the result of one of three conditions: asthma, rhinitis/sinusitis and gastroesophageal reflux disease.

Asthma and rhinitis/sinusitis are frequently the result of allergies and so a history of allergies or a positive allergy evaluation strengthens the likelihood that one of these conditions is behind the cough.

Gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux disease (LPR) are conditions associated with the leakage of stomach contents into the esophagus.  In GERD, stomach acid refluxes into the lower esophagus causing irritation and damage.  Exposed nerves in the esophagus can cause cough as well as pain (heartburn).  In LPR, stomach contents may reach to the top of the esophagus causing direct irritation of the throat and possible sinuses.  The throat and upper airway are lined with cells that produce mucous as well as cells that have hair-like projections or cilia that sweeps the mucous to the back of the throat where it is swallowed.  Acid and protein-destroying enzymes in the refluxed stomach contents inflame and  damage the hair cells, hindering the ability to clear mucous.  The result is pooling of mucous in the back of the throat and recurrent cough to clear it.  It is estimated that 50% of patients with LPR have no other symptom of their condition other than cough and is therefore frequently missed.   GERD and LPR should be suspected if an evaluation for allergies, asthma, and sinus disease is negative and the cough fails to respond to conventional treatment.

It it a Cold, Sinus Infection, or Allergy?

In Arizona, one of the challenges patients and physicians face during February and March is determining if that runny nose, scratchy throat, and sinus pain is the beginning of the spring allergy season, a late winter cold, or worse.  Here are a few clues to help sort it out.

  1. Allergy itches.  Most seasonal allergy attacks involve itching, either of the eyes, the nose, the throat, or skin.  When an allergic reaction occurs, histamine is released into the tissues causing redness, swelling, and itching.  Histamine is also released during a viral cold (which is why antihistamines are frequently prescribed for a cold) but this is not the primary chemical mediator causing symptoms.  If there is no itching, it probable isn’t allergy.
  2. Colds last about a week. Viral cold symptoms peak around day three, begin to level off by day five, and then begin to resolve.  You may not be well by the seventh day but you should be significantly better compared to how you felt on day three.  A sinus infection is usually a viral cold that becomes complicated by a bacterial infection.  It begins like a cold but rather than getting better by day seven, things are getting worse with increased discharge, pain, and possible fever.  You should see a doctor if cold symptoms persist or worsen beyond the seven day mark.  The allergy timeline is much less predictable with allergy symptoms coming and going throughout the season.
  3. Everyone else is sick.  If everyone in your cubicle, classroom, or home has the same deep cough or sore throat, it is likely a cold.  During a rough allergy season, a lot of people may be sneezing at the same time, but those affected do not cluster in a family, school,  or work-place the way a communicable virus does.
  4. Olive trees in winter.   If you know what you are allergic to (Olive trees, for example) and you know when they pollinate (Olive tree in April), it is unlikely that your February and early March symptoms are caused by allergies (if Olive is the only thing your allergic too).


Normal Sinus Function
The sinuses are cavities within the cheek bones, around the eyes and behind the nose. Although their precise function is not known, it has been suggested that they play an important role in warming, moistening and filtering the air in the nasal cavity, resonating vocalized sound, and keeping the weight of the skull at a manageable level. One thing is true, the sinuses are constantly at risk of attack from viruses, bacteria, and mold looking to move into the warm, dark, moist, and nutritious environment of the sinus cavity.

The sinuses primary defense against invasion is drainage. Seen under the microscope the sinuses are lined with a tall cell with waving, hair like projections called cilia. There are also numerous mucous glands that provide a constant layer of mucous that is kept in motion by the sweeping cilia. The mucous moves in a coordinated manner around the sinus lining eventually being swept out of small openings in the sinus called the ostia. The sinus ostia are located under wing-like bony structures in the nasal passage called the turbinates. Mucous draining from the sinus ostia is directed backwards toward the throat were it is swallowed. Normal sinus drainage occurs throughout the day and usually goes unnoticed. When the amount of the mucous increases significantly or the character of the mucous changes we may experience it as post nasal drainage.

The coordinated flow of mucous is critical to the health of the sinuses. The mucous not only contains enzymes and antibodies that kill specific pathogens, but the constant tide of flowing mucous prevents viruses and bacteria from infecting the cells lining the sinus causing disease. Oxygen is toxic to many harmful bacteria but necessary for the health of cilia. It is therefore important that the sinuses remain open to the air. When the sinus ostia become plugged – as can occur with allergy, anatomical narrowing or polyps- the mucous becomes thick and stagnant, the oxygen level in the sinus drops, the cilia cannot function normally and bacteria are given an opportunity to grow and cause infection To fight back the sinuses will try to flush out the invaders by producing more mucous. Without proper drainage, however, it is a difficult fight to win. As a secondary defense measure, the lining of the sinus may become thickened.

Inflammation of the sinuses is called sinusitis. This inflammation may be the result of infection, injury, and allergy and can be acute or chronic.

Acute sinusitis is characterized by symptoms lasting less than 4-6 weeks and is usually caused by infection. Symptoms of acute sinusitis are familiar and include pressure around the nose, eyes or forehead, stuffy nose, thick, discolored nasal drainage, post-nasal drip, cough, head congestion, and ear fullness. Some patients with acute sinusitis may also complain of a toothache and occasionally fever.

Acute sinus infections may be caused by viruses or bacteria. The common cold virus frequently infects the sinuses resulting in sinus pressure, discolored nasal discharge, and post nasal drainage. These symptoms will typically begin to improve after 5-7 days without treatment. When symptoms persist beyond a week, or worsen suddenly, it is often because a bacteria has moved in, taking advantage of the weakened condition of the sinuses caused by the cold virus. For many doctors and patients the term “sinus infection” refers to a bacterial infection of the sinus requiring an antibiotic. Because even the best doctor cannot tell the difference between a viral and a bacterial infection based on history of physical exam alone, it may be appropriate to reserve antibiotics for symptoms that have lasted 7-10 days without improvement.

Inflammation of the sinuses lasting for more than 4-6 weeks is called chronic sinusitis. The symptoms of chronic sinusitis may be subtle and limited to recurrent post nasal drainage, frequent throat clearing, recurrent cough, nasal congestion, poor sense of taste or smell, and stuffy ears. The cause of chronic sinusitis may be a bacterial infection that the body has not been able to completely clear, reaching a kind of “stale mate”: the infection is not progressing but the body isn’t getting rid of it either. As a result of the persistent infection, the lining of the sinus may become thickened and drainage less efficient. It is theorized that in some cases a bacterial infection will injure the lining of the sinuses to such a degree that even when the infection is eradicated, poorly functioning cilia, thickened sinus membranes, and inefficient drainage persists.

Some types and mold may find there way into the sinus cavities and begin to grow. Some researches feel that mold in the sinuses is an important causes of chronic sinusitis. Others feel that chronic sinusitis presents an opportunity for fungus to grow, and is therefore an innocent bystander in the disease process. Some mold varieties are highly allergenic and if you are allergic to mold that is growing in the sinuses, symptoms of severe sinusitis and asthma may develop.

Allergies to air-born allergens such as pollen, mold, and animal dander may increase the risk for developing sinusitis because allergies can cause swelling of the nasal tissues limiting normal sinus function. The sneezing, sniffling, and nasal congestion associated with hay fever may increase the chance of bacteria in the nasal cavity finding it’s way into the sinuses.

Management of allergy symptoms with medications and immunotherapy may reduce the likelihood of developing an infection.

In rare cases, immune problems that limit the bodies ability to fight common infections may present with chronic or recurrent sinusitis.

Structural abnormalities of the nasal cavity, such as narrow sinus ostia, tumors or a shifted nasal septum (the bone and cartilage that separate the right from the left nostrils), may also cause sinusitis. If the problem is structural then surgical correction may be curative, however, because many patients with recurring or chronic sinusitis have more than one factor that puts them at risk of infection. a proper evaluation and accurate diagnosis is essential. You cannot fix an allergy problem with surgery.

Sinusitis in a Desert Environment

Living in Phoenix presents unique problems for the sinuses. The sinuses need a constant flow of mucous to stay healthy. Individuals who grew up in a humid environment like Chicago, Portland, or Atlanta and then move to Ahwatukee, Chandler, or Maricopa, may suddenly find that the dry climate of their new home does not provide enough moisture to keep the sinuses functioning as usual. Like the excessive tearing associated with chronic dry eyes, the sinuses may respond to the dry conditions by producing too much mucous, leading to post nasal drip syndrome. In addition, the amount of suspended fine particles in the air such as quartz and diesel particles, is greater in the desert, and when breathed can damage the lining of the nose, sinuses, and airways leading to tissue injury and chronic inflammation. The inflaming effect of particulates and other air pollutants may heighten the effect of air-born pollen and mold. The result if more severe allergies, asthma, and sinus problems.

Sinusitis Versus Rhinitis

Symptoms of sinusitis and rhinitis are very similar. Rhinitis is a swelling of the mucous membranes of the nose while sinusitis includes swelling of the sinuses in addition to the nasal passages. For this reason, sinusitis is often called rhino-sinusitis.

Rhinitis may be allergic or non-allergic. Symptoms of allergic rhinitis often are a runny nose, sneezing, nasal congestion and itchy eyes, nose, throat and ears. People with non-allergic rhinitis may have a very stuffy or a very runny nose. It may be caused by irritants such as air pollution, dryness, smoke, changes in barometric pressure or temperature or overuse of over-the-counter decongestant nasal sprays.


The evaluation of sinusitis should include a detailed history and physical examination. Allergy testing is needed to differentiate allergic from non-allergic rhino-sinusitis. A sinus CT scan may be needed to look for evidence of infection or structural abnormalities. If in doubt, tests to insure that the immune system is in proper working order may be ordered.


Acute bacterial sinus infections are treated with antibiotics and if needed, agents to reduce inflammation and promote drainage Chronic sinusitis can be a challenge to treat for a number of reasons. The inflammation in chronic sinusitis is similar to that seen in chronic asthma. Although the inflammation is asthma is routinely treated successfully with inhaled steroids, we do not have a way to get topical steroids into the sinuses. In fact, the nasal passage and turbinates are designed to keep things from entering the sinuses from the nose. So although nasal steroids are frequently used to reduce nasal congestion, very little makes it into the sinuses. Oral steroids, can provide significant improvement in sinus symptoms but have significant side effects if taken for more than 1-2 weeks. Antihistamines are not helpful in chronic sinusitis for the same reason that they are not helpful in chronic asthma: the inflammation involves many different cells and chemicals besides histamine. Several non-drug treatments can be helpful including breathing warm, moist air and irrigating the nasal cavities with salt water.

For people with allergies, long-term treatment to control and reduce nasal congestion and other allergic symptoms can help in preventing sinusitis.