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.