The Allergy Clinic
Specialists in Allergy & Asthma Care
Specialists in Allergy & Asthma Care
Poiseuille's Law
In AnArmyOfPlacebos we talked about how it sometimes take a few tries to relieve a stuffy nose when we're not
allowed to use strong drugs like Sudafed (pseudoephedrine). That column failed to mention Breathe Right® nasal
strips as a helpful adjunctive treatment for stuffy nose. These adhesive strips stick to the outside of your nose, and pull
it open just a little bit to partially relieve the congestion.
congestion.
Poiseulle determined that the laminar flow rate of an incompressible fluid along a pipe is proportional to the fourth
power of the pipe's radius. In other words, you need sixteen tubes to pass as much fluid as one tube twice their
diameter. In the case of the Breathe Right nasal strip, we're not doubling the radius of your nasal passage; just
increasing it a bit.
But consider the example of a 7 mm passage that increases to 8 mm. 7 to the 4th power is 2401.
7x7x7x7=2401
8 to the 4th power is 4096!
8x8x8x8=4096
In other words, you almost doubled the amount of air that can flow through your congested nostril just by
increasing the diameter 1 millimeter.
Sorry for all that math, but I love to point out that staying awake in high school physics class does have a point, after all.
A few tips from veteran users of Breathe Right nasal strips. First, the adhesive is good, but not great. So clean the oil
off your nose well before application so the adhesive will stay put. Second, you need the strip sticky at its ends, but not
in the middle. Some patients put a little dab of Kleenex in the middle of the strip before application so it doesn't stick to
the bridge of your nose. Then, removing it doesn't peel off your skin. Ouch!
Here is a link from their web site on the mechanism of action. It is a 13 page paper to download with Adobe:
www.breatheright.com/whitepaper
In AnArmyOfPlacebos we talked about how it sometimes take a few tries to relieve a stuffy nose when we're not
allowed to use strong drugs like Sudafed (pseudoephedrine). That column failed to mention Breathe Right® nasal
strips as a helpful adjunctive treatment for stuffy nose. These adhesive strips stick to the outside of your nose, and pull
it open just a little bit to partially relieve the congestion.
congestion.
Poiseulle determined that the laminar flow rate of an incompressible fluid along a pipe is proportional to the fourth
power of the pipe's radius. In other words, you need sixteen tubes to pass as much fluid as one tube twice their
diameter. In the case of the Breathe Right nasal strip, we're not doubling the radius of your nasal passage; just
increasing it a bit.
But consider the example of a 7 mm passage that increases to 8 mm. 7 to the 4th power is 2401.
7x7x7x7=2401
8 to the 4th power is 4096!
8x8x8x8=4096
In other words, you almost doubled the amount of air that can flow through your congested nostril just by
increasing the diameter 1 millimeter.
Sorry for all that math, but I love to point out that staying awake in high school physics class does have a point, after all.
A few tips from veteran users of Breathe Right nasal strips. First, the adhesive is good, but not great. So clean the oil
off your nose well before application so the adhesive will stay put. Second, you need the strip sticky at its ends, but not
in the middle. Some patients put a little dab of Kleenex in the middle of the strip before application so it doesn't stick to
the bridge of your nose. Then, removing it doesn't peel off your skin. Ouch!
Here is a link from their web site on the mechanism of action. It is a 13 page paper to download with Adobe:
www.breatheright.com/whitepaper
