allergies
Introduction
Allergies may affect up to 40 million people in the United States every
year. The manifestations of allergies range from annoying symptoms of a
runny nose and sneezing to life threatening obstruction of breathing. Many
people may only have allergy symptoms for a few weeks out of the year,
while others are bothered by repeated sinus infections or asthma. For the
pilot, there are effective treatments for almost the entire spectrum of
allergic symptoms that will not ground the pilot, or are easily waiverable
after proper reporting.
Terminology
The most common manifestations of
allergies is the runny nose (rhinitis), sneezing and itching eyes. These
symptoms may be seasonal when certain grasses, flowers, trees or molds
shed pollen or spores (Seasonal Allergic Rhinitis or SAR). Some
individuals are plagued with these symptoms nearly continuously regardless
of the season (Perennial Allergic Rhinitis). These people may be sensitive
to dust, animal dander or other common materials.
Non-allergic rhinitis, also known as vasomotor rhinitis or irritant
rhinitis, may be caused by smoke, fumes, odors, chemicals or other unknown
sources, may cause symptoms year-round. Common colds, caused by rhino
viruses, may have similar symptoms of congestion and runny nose, but are
not usually associated with itching eyes. Colds usually resolve within
five to ten days and do not occur regularly with a particular season.
Immune System
and Allergic Responses
Allergies are caused by the body’s
reaction to outside proteins or particles (allergens). The immune system
releases chemicals from certain blood cells and tissues called histamines
that cause a reaction to the allergens. Generally, the mucus membranes
near the site where the allergen reaches the body react by swelling and
leaking clear fluid. The tissue is also irritated giving a scratching,
itching sensation.
There are a variety of methods for testing for allergies. They include
skin tests such as patch testing, intradermal testing and scratch/prick
testing. Blood testing is used to look for evidence of allergies in the
body. A complete description of each type of testing is found in the
August 15, 2002 issue of American Family Physician in Allergy Testing.
There is also a Patient information handout: "Allergy Testing"
If the sinus passages are constantly swollen and filled with fluid, an
excellent culture site is created for bacteria in the respiratory tract.
Sinusitis, ear blocks and sinus blocks may result, particularly with
repeated changes in atmospheric pressure. In more severe cases, the
histamines and other chemicals released by the body may act not only on
the local site of exposure, but on the entire body. The result may be an
asthma attack as the breathing airways swell, leak fluid and close down.
Allergies can also cause itching over the entire body.
Prevention by Avoidance
Allergies may be prevented or treated. The most effective prevention is
avoidance of the allergen. This is often not practical for the pilot who
flies all over the country or is based in a region filled with numerous
allergens. Ironically, many pilots note their allergies will improve when
they are flying since the cabin air at altitude is usually relatively free
of allergens. If someone is allergic to animals, such as cats, getting rid
of the animal may cure the symptoms. Many allergy suffers are unable to
avoid or even identify the cause of their symptoms.
Preventive
Medication- Nasal Steroids
Another method of prevention is
the use of medication to block the body’s reaction the allergens. The most
common symptoms of nasal stuffiness are effectively relieved by nasal
steroid sprays. These steroids act by stabilizing the cells in the body
exposed to allergens so they do not release histamines. They are not
immediately effective, but may take several days to weeks to reach their
full effect. If someone can anticipate their allergy season, using they
agents several weeks before the season starts may block most symptoms. The
steroid nasal sprays should not be confused with anabolic steroids, often
illegally used by body builders and athletes.
The nasal steroids are usually well tolerated and act on the nose and
upper respiratory tract. They are relatively safe for long term use and
the FAA will approve their use if they are effective. Reporting their use
to the FAA may be done at the airman’s next physical exam. Some of the
name brands for these effective products are Beconase, Vancenase, Flonase,
Nasalide, Nasacort, Nasonex, Nasarel and Rhinocort.
The Agency for Healthcare Research and Quality Review of Treatments for
Allergic and Nonallergic Rhinitis published in American Family Physician
indicates that nasal steroids are preferred over antihistamines treatment
for allergic rhinitis.
Non-steroid
Nasal Sprays
These nasal non-steroid sprays
should not be confused with nasal decongestant sprays such as Afrin and
Dristan which can not safely be used for more than several days and are
not permitted by the FAA, except as an emergency "get me down" for sinus
and ear blocks occurring in flight.
Cromolyn is an example of a FAA approved non-steroid medication for
control of allergic symptoms. It is most effective for relieving itchy
eyes when used as a eye dropper or nasal spray.
Atrovent nasal spray decreases nasal secretions in both allergic and
non-allergic rhinitis. The FAA will authorize its us when flying after an
appropriate observation period without side effects.
Preventive
Medication - Over-the Counter Antihistamines
Antihistamines work by a different
mechanism from nasal steroids, but also result in blocking the body’s
allergic response. Antihistamines are available over-the-counter (OTC) or
by prescription.
Very few OTC antihistamines are authorized by the FAA for pilots when
flying, if they have previously tested the medication and do not have any
side effects. The primary OTC antihistamine, Claritin, was formerly
available by prescription only. It is the same medication as the
prescription formulation Clarinex. See a summary of its effectiveness in
the American Family Physician article, Desloratadine for Allergic Rhinitis
(Nov 1, 2003).
The over-the-counter products such as chlorpheneramine (Clortrimaton, CTM)
and diphenhydramine (Benadryl) found in many commercial products cause
drowsiness. They are not permitted by the FAA and a pilot should wait at
least twice as long as the dosing recommendation after the last dose to
fly. For example, if the directions read take every six hours", the pilot
should wait at least twelve hours after the last dose before considering
flying. These medications may have subtle adverse effects for much longer
in some individuals. Chronic treatment with over the counter
antihistamines requires a 24 hour wait after the last dose before flying,
according to the FAA Guide for Aviation Medical Examiners.
A study published in the Annals of Internal Medicine on 7 March 2000
demonstrated that the effect of taking Benadryl, an OTC antihistamine,
impaired driving performance significantly more than a blood alcohol
concentration of 0.1% (legally intoxicated) or Allegra, a "non-sedating"
antihistamine. It also demonstrated that subjective drowsiness was not an
accurate measure of driving performance. Two of the study's authors are
consultants to the manufacturer of Allegra.
Preventive
Medication - Prescription Antihistamines
The non-sedating antihistamines
are available by prescription only. The FAA will allow a pilot to use some
of these medications and fly if they tolerate them without any side
effects after a ground testing period of several days. The currently
approved medications are Allegra, Clarinex and Claritin. Seldane and
Hismanal have been removed from the market by the manufacturer. Claritin
became available without a prescription in December 2002.
Zyrtec, another medication in this category, is not approved by the FAA. A
24 hour wait is required after the last dose of Zyrtec is required before
flying.
Astelin, a nasal spray form of antihistamine, is not approved for use when
flying. Just as with Zyrtec, a 24 hour wait after the last dose is
required before flying.
Like the nasal steroids, the use of the approved medications may be
reported at the airman’s next FAA physical. Those approved medications
that are combined with pseudoephedrine, the active ingredient in Sudafed,
are also approved by the FAA. They include Claritin-D, Clarinex-D and
Allegra-D.
Decongestants
Decongestants, such as Sudafed,
are often used with allergies to constrict blood vessels in the nose and
relieve the running nose. Pseudoephedrine, found in Sudafed, is approved
for use while flying. This medications acts throughout the entire body by
constricting blood vessels. Side effects may include an increased heart
rate, elevated blood pressure and difficulty urinating in men with
prostate problems. Because it frequently keeps individuals awake, it is
often combined with non-approved antihistamines sold over the counter.
These combinations of decongestants and OTC antihistamines are not
approved within twelve hours of flying.
Severe cases of allergies may cause asthma or other symptoms that require
treatment with oral steroids such as Prednisone or Medrol, or steroid
injections. Pilots having symptoms severe enough to require this type of
treatment should not fly until the condition is resolved.
Desensitization
- Shots - Immunotherapy
The FAA will approve pilots to fly
when undergoing treatment with allergy desensitization shots. Pilots
should be cautious flying immediately after receiving higher
strength/concentration serums to insure they do not have a delayed
allergic reaction. See the American Family Physician article on Allergen
Immunotherapy and a patient handout on the subject.
FAA Reporting
Requirements
The reporting of SAR or other
allergies controlled with approved medications should be done on FAA Form
8500-8. In block 17, Medications, list the medication used and dose. In
the physician visit section, list the name of the physician with date or
range of dates of visits. For reason for visit, list "Allergic Rhinitis-
treated and controlled. No side effects", assuming this is true. See the
AME Decision Making Guide.
Recently, some pilots who have listed Claritin, Clarinex or Allegra as
medications they are using to control allergic symptoms have received
letters from the FAA indicating the use of these medications are
prohibited within 48 hours of flight. These letters were sent because the
pilot or AME did not make comments on the FAA Form 8500-8, Airman Medical
Application, that the medication was tolerated without side effects. A
comment on the application regarding the absence of side effects would not
result in a restriction. Discussion with representatives of the FAA
confirm that pilots who do not have any side effects from Allegra,
Clarinex or Claritin may disregard these letters, but should note the
absence of side effects on their next physical.
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