April 16, 2014
by Megan Stauffer

Stress and Allergies

We all know stress isn’t good for our health. It increases the risk of developing high blood pressure and diabetes and contributes to increased levels of anxiety and depression.

Now a study in the Annals of Allergy, Asthma and Immunology shows that people who are experiencing stress are more likely to have a flare of their allergies. Many of the patients in the study reported an allergic flare within days of the increased stress. Additionally, allergy suffers with more chronic stress experienced allergy flares more often.

The authors recommend ways to alleviate stress, such as meditating, making time for relaxing and adopting a healthy lifestyle. Certainly decreasing stress is good for your overall health, but be sure to see a board-certified allergist to get a comprehensive plan for managing your allergies.

-Dr. Megan


April 10, 2014
by johnoverholt

The Science of a Sneeze

I love science:  chemistry, physics, engineering, math. It’s a big reason I became a doctor. So when scientists at Massachusetts Institute of Technology published a paper in the Journal of Fluid Mechanics on sneezing, I got pretty excited. How nerdy is that? Anyway, regardless of your level of nerd-cred, the article had some important and interesting new findings — and it has a high-speed video of a sneeze.

What you’re seeing there is not just a simple sneeze, it’s a multiphase turbulent buoyant cloud. That means that when you sneeze, the gasses you emit mix with the surrounding air (“multiphase”) in a violent, roiling fashion (“turbulent”) that results in a floating (“buoyant”) cloud. We used to think that the distance a germ could travel in a sneeze was limited to the distance the large droplet particles could travel, essentially the spray that you can see and feel from a sneeze. We also thought that larger particles traveled the farthest due to their greater momentum. The new gas cloud model turns that understanding on its ear. It tells us that the smaller particles travel the farthest because the cloud keeps them suspended in the air while the larger particles fall out. In fact, these small particles can travel five to 200 times farther than we previously thought! Some very small particles even had the potential to reach air ventilation intakes that could then circulate them elsewhere in an indoor environment.

In practical terms, this might change the way ventilation systems are designed, especially for higher risk locales like hospitals, schools and airplanes. Better air systems with less germ transmission could result in real gains in public health:  fewer cases of hospital-acquired pneumonia, fewer influenza outbreaks in schools, and less anxiety about the guy three rows behind you on the plane coughing his head off. For now, though, the CDC still recommends that we sneeze into our elbow and wash our hands after sneezing — very good recommendations.

If you want to dig a little deeper and read about it from the people who really know what they are talking about, try this press release from MIT. If you read it, let me know what you think, and I’ll put your official nerd certificate in the mail.

Dr. O

April 8, 2014
by johnoverholt

A New Treatment For Hives

Chronic hives make people miserable. They affect all facets of life — work, sleep, relationships, mood — and they can be relentless. Most folks who suffer from persistent hives can get adequate relief with simple, long-acting antihistamines like cetirizine (Zyrtec) or fexofenadine (Allegra) if taken in adequate doses (sometimes two to three times the usual daily dose). If these don’t work, then super-potent antihistamines like hydroxyzine or doxepin are the next step, but both are very sedating.

Sometimes even these very strong medications don’t work or the side effects are just intolerable. In the past, severe patients had very limited treatment options, usually potent immune suppressants like cyclosporine; but now there’s a new option in the form of a not-so-new medication:  omalizumab (Xolair).

I’ve blogged about omalizumab a couple of times, and I gave a rundown of how it works way back in 2009. In simplest terms, it disarms the body’s allergy cells, making it nearly impossible for them to mount an allergic reaction. Because these cells are responsible in large part for causing hives, it makes sense that omalizumab would work in such cases, and now there are good studies to show that it is, indeed, effective when antihistamines fail.

So how effective is it? I would say moderately effective. Studies show that only about a third of folks who took omalizumab injections once a month got total relief and about two-thirds had a good response. It took up to two weeks to see improvement, and once they stopped taking omalizumab, the hives came back. On the good side, omalizumab is very well tolerated.

The important message here is this:  you needn’t be miserable from chronic hives. Numerous good treatment options exist. To find which is most appropriate for you, go see your local board-certified allergist and get better.

March 13, 2014
by johnoverholt

Allergies are Universal in the U.S.

No matter where you go, there you are. – Buckaroo Banzai

Spring allergy season is upon us, and in Middle Tennessee it’s the time of year with the most acute allergy misery. All the sneezy, itchy, runny noses drive many patients to the allergist where they often wonder aloud, “I never had problems like this until I moved here. Would it simply be better for me to move somewhere else?” One recent study suggests the answer to that question is “No.”

No one is born with allergies. Whether people develop them, like most medical problems, depends on the combination of genetics and environment, nature and nurture. Certain people are born with a tendency – the genetic component – to develop allergies.  At some point they become exposed to allergens like tree pollen, cat dander or peanuts – the environmental component. If a person’s genetic tendency is strong and the exposure has the right amount, timing and route of administration, then a clinical allergy may develop.

The genetic side of this formula is set in stone. You can’t pick your parents. The exposure side, however, is variable. Tennessee has more tree pollen than Phoenix. Humid areas (Mississippi) have more dust mites than arid climates (Colorado). Urban areas (Baltimore) have more cockroaches and cat dander than rural areas (Beaver Dam, KY).  So you would think that the prevalence of allergies would be higher in areas with a greater environmental allergy loads. But, you’d be wrong.

A recent study looked at the prevalence of positive allergy tests in all areas of the U.S. and found that the numbers were pretty much the same wherever you live. A whopping 44.6%(!) of U.S. adults are sensitive to at least one allergen. In kids ages 1-5, that number is 36%. Interestingly, the rates didn’t vary from region to region, though they were a little higher in urban areas, 50%, vs. rural areas, 40%. Rates of sensitization to individual allergens did differ. For example, the South had more dust mite allergy and the West had more pollen allergy, but the overall rates remained constant.

So what does this all mean? It suggests that the genetic component of allergies is much more important than the environment. If your body has an allergic tendency, it’s going to find an allergen to react to no matter where you live or what you try to avoid. You can avoid specific allergens, but you can’t avoid all of them, and you can’t run from your genetics.

This is where the allergist comes in. We actually have the tools to make you less allergic to your specific allergens. We can teach your immune system to ignore your triggers, which will shut off your allergies at the source and give you systemic relief, fewer symptoms and fewer complications while using fewer or no medications. So before you pack up for Denver, try giving you local, board-certified allergist a visit first.

Dr. O

March 5, 2014
by johnoverholt

Allergy Shots Reduce Sinus Infections, Sore Throats

Allergies are much more than just a runny nose. We all know they can cause  the acute misery of sneezing, itchy eyes and nasal congestion, but they affect people in numerous other ways. One of the most common complications of allergies is an increase in upper respiratory infections. URIs include sinusitis, pharyngitis (sore throat), tonsillitis, and the common cold.

Multiple studies have shown that allergy shots will reduce the direct symptoms of allergies, and now a recent study has helped quantify exactly how much we can expect them to help with the complications. Data presented at this year’s AAAAI meeting show that patients who take allergy shots are overall three times as likely to have fewer URIs than patients who do not. The study used a large Medicare database from Florida and compared several thousand allergy shot patients with matched controls. The study found that allergy shot patients were:

  • twice as likely to have fewer sinus infections
  • four times as likely to have fewer episodes of tonsillitis
  • eight times as likely to have fewer sore throats, and
  • 35 times as likely to have improvement in nasal polyps.

These findings confirm what we’ve been saying all along — If you’re having complications from allergies, you need to see a board certified allergist so you can get tested, get treated, and get better.


Dr. O

January 14, 2014
by Megan Stauffer

Preventing Food Allergy During Pregnancy

Can a pregnant woman do something to prevent her child from having food allergies? There has been much debate surrounding this question over the years. In the past, allergists recommended pregnant women try to avoid nuts during pregnancy; however, current recommendations are that maternal avoidance diets are unsucessful in preventing the development of an allergy and are therefore not recommended.

A new Harvard study published in JAMA Pediatrics provides some new insight. This study examined the association between maternal comsumption of nuts and the risk of having children with a nut allergy.  They found that mothers who were not allergic and who ate nut products more than five times per month were significantly less likely to have a child with a nut allergy. This finding is consistent with new recommendations about introducing highly allergenic foods earlier in life as a way to help prevent the development of food allergies, and it suggests that early exposure to allergens may help promote tolerance to these allergens.

Dr. Megan





December 18, 2013
by johnoverholt

FDA Advisory Committee Supports Two New Sublingual Grass Tablets

The FDA advisory committee has recommended approval of two new sublingual tablets for the treatment of grass allergy.  The FDA is not bound to follow the recommendation of the advisory committee, but it usually does. So, what does this mean for you, dear reader?

First off, the word sublingual means “under the tongue”. These new treatments are a form of sublingual immunotherapy, or SLIT. I’ve blogged about the pros and cons of SLIT before and they still hold true today. In short, subcutaneous immunotherapy, aka SCIT, aka allergy shots, is probably more effective, works quicker, lasts longer and is better at preventing new allergies and complications. SLIT is more convenient and safer. Compliance is pretty poor for both.

The big drawback for the new grass SLIT tablets is their lack of flexibility and their narrow focus. One tablet contains only Timothy grass – a representative pasture grass – and the other contains a mixture of pasture grasses. This is great if all you have is pasture grass allergy; but if you have hot-weather grass allergy, like Bermuda and Bahia, or if you’re allergic to any of the other myriad allergens, like trees, weeds, dust mites, cats, dogs, cockroaches or molds, then you’re out of luck. In my practice, I would estimate that less than 1% of my allergic rhinitis patients are sensitive to only pasture grass. Allergy is regional, so this might be different elsewhere.

Perhaps more important than the individual tablet approvals is the fact that the FDA might approve SLIT at all. Up until now, SLIT has been a strictly off-label practice in the U.S. and, because it lacks FDA approval, it has not been covered by insurance. This certainly won’t lead to wholesale SLIT approval across the board, but it does get a foot in the door. For SLIT to be a meaningful treatment for most allergy sufferers it will have to be individualized and the approval process for that will be more complicated.

Stay Tuned.

Dr. O

December 17, 2013
by johnoverholt

In a Lather Over Soaps

What is it she does now? Look how she rubs her hands.

It is an accustom’d action with her, to seem thus
washing her hands. I have known her continue in this a quarter of
an hour.

Lady Macbeth:
Yet here’s a spot.

Hark, she speaks. I will set down what comes from her, to
satisfy my remembrance the more strongly.

Lady Macbeth:
Out, damn’d spot! out, I say!

-Macbeth, Act V, Scene i

Germophobes rejoice! Or revolt! I’m not sure which, but the FDA is now going to require that manufacturers of anti-bacterial soaps prove that their products are safe over time and that they work better than plain soap and water. Your hand sanitizer is still safe, for now.  A bit more from Jeff Bezos’ Washington Post.

Dr. O