I know this isn’t particularly related to Alaskan aviation, but the topic of space tourism is increasingly coming up on my radar screen, and I find it an incredibly interesting subject. I recently attended a “Humans in Space” conference in Austria, and it brought out the space groupie in me again. I promise to come back next time to an aeromedical topic more likely to be useful to the GA pilot. In the meantime, I hope you find this article interesting.

Within the next handful of years, commercial space travel, at least at a suborbital level, will open up for nearly any individual who has the financial means to purchase a ticket to ride. So far the only commercial space tourists have been adult men who had undergone extremely extensive medical evaluations by the Russian space agency prior to selection. Two men have flown, and a third is currently being evaluated. * Among those that have been turned down is the rock singer Lance Bass, of N’Sinc.

Subsequently these 2 men spent the next few months engaged in intensive physiological and operational training in Star City (the Russian equivalent of Johnson Space Center in Houston) and were being turned into cosmonauts. They were being prepared for several days in microgravity on board the Russian segment of the International Space Station. They would be subjected up to 7 G’s, possibly endure severe space motion sickness, and be expected to perform some tasks. Mostly, though, there were required to stay out of the way of the “real” astronauts. (It was purported that NASA required Dennis Tito to sign a breakage agreement and to agree to stay away from the US segment of the ISS.) The Russians rely so heavily on the income from these super wealthy space tourists that some cosmonauts actually threatened to boycott their NASA training if Mr Tito was not allowed to fly. It seems somewhat ironic that the former communists are now heavily involved in the commercial side of space, yet our own capitalist country has been very slow to embrace such an expression of the American dream. To be able to be counted among the elite 600 or so astronauts and cosmonauts around the world is worth $20 million to a select few.

Certainly the future of commercial space travel does not lie long the same path. This next generation of space tourists will consist primarily of upper income middle-aged men (and to a lesser extent, women) with substantial disposable income but little time for preparatory training. Many will come with a list of medical problems, some of which they do not yet even know they have. If the price of a flight and the time involved in training would come down, then there would be many more people who would sign up.

Presently there are a number of small companies involved in developing suborbital flight infrastructures for commercial space tourism. These companies are toying with various flight profiles which are the basis from which potential medical guidelines need to be considered. In general these flights at first will be of relatively short duration, most likely under an hour with only a few minutes’ exposure to microgravity. Passengers will be exposed to relatively low G-forces, on the order of 2-4.5 and sea level (or at least departure ambient) cabin pressures. There will be little, if any, requirements to act independently such as emergency egress activities. Some companies might offer a flotation experience, which would require additional training in removing and then re-attaching the seat restraints. There should not be any need for personal protective equipment, although some companies are developing spacesuits as part of their program.

Further down the road will be designs for longer vacations such as orbiting hotels. We are still a few of generations away from long-distant space flight for tourists, such as to Mars. There have been some publications in the aerospace medical literature on this topic, but only by giving rough guidelines and suggestions.

What, then, should the medical standards for these new up-and-coming space tourists be, and who should oversee this activity? Currently the state of understanding of the medical aspects of space flight is limited to the study of incredibly healthy and strong adults. Nothing is really known about the effects of space flight of any kind on people with significant medical problems, nor such normal physiological states such as pregenancy. Scientists really don’t know much about the effects of the space environment on the ordinary person.

In order to make decisions about potential space passengers’ health, some assumptions need to be made based on the state of the industry. For the foreseeable future, these flights will be similar to the recent flights of SpaceShipOne: low G’s gentle ride up, a few minutes of weightlessness up at the top at 100 km, an incredible view of earth, probably some nausea and maybe vomiting, a fast return flight, and a firm landing back where you started from. For the healthy adult, a few days of orientation including gentle centrifuge training and a brief health check should be all that is needed to prepare for such flights. In such a profile, even people with a significant physical disability, such as paralysis or blindness, should not be excluded from this trip as long as they can physically safely occupy a seat. However, individuals with a serious medical or psychiatric illness that is not stable, should be excluded. Cases like this would include people with uncontrolled siezures, unstable heart disease, or severe anxiety. On the other hand, individuals with terminal illnesses should be allowed to fly, as long as they are otherwise fit to fly, and not likely to succumb of their illness during the flight. Of course, a myriad of psycho-social problems related to isolation need to be solved before any long term flights can be engineered.

That actually leaves a lot of people out there who can fly. Within the parameters of such simple and short “shirt-sleeve” suborbital flights, it seems that most adults who are healthy enough to drive should be able to be space tourists.

Whether or not the future of commercial space travel will extend to the realm of long duration flight, such as to Mars, depends entirely of course on the economic environment at the time, but also requires a real understanding of what happens to normal people, not just physically fit astronauts, during such extended flights. For the long haul traveler, many serious physiological problems must be overcome, such as dealing with the considerable amount of muscle and bone lost due to the lack of gravity. There are a lot of fluids in the body that are shifted about as well which can create havoc in people with circulatory problems. Space engineering has not yet been able to provide a viable spacecraft that creates its own artificial gravity.

As far as regulation, the FAA is actually staying out of it for now. They have requested input from professional organizations such as the Aerospace Medical Association, which has made some very general recommendations. It is hoped that the industry will regulate itself in this regard, with each individual company setting up its own medical guidelines and screening procedures, dictated by current knowledge and good common sense. What is not regulated will be managed by the attorneys. It is to the companies’ advantage to have some sort of reasonable medical screening and physiological training program for their customers.

When space tourists start flying regularly, we will learn more about how the normal, relatively untrained human responds to various levels of space conditions. We will be able to learn whether it is safe for people in special medical situations to fly, such as pregnant women, and what, if any, the limits of age on either end should be. I believe that the legal community will develop more stringent standards than the government would, and the industry will need to support the kind of research needed to increase and refine our understanding.

Virgin Galactic is planning to be flying by 2008, and is already taking deposits. Are you ready to be a Space Cowboy?

* Dennis Tito (USA) age 60,Soyuz TM-32, April 2001

Mark Shuttleworth (S. Africa) age 27, Soyuz TM-34, April 2002

Life is sweet, especially when one lives in Alaska and has an opportunity to fly wonderful airplanes to incredible places. However, when sweetness affects your body, not only is your health in jeopardy, but so is your Medical Certificate. As an Aviation Medical Examiner, I have encountered many diabetic pilots in my 20 plus years of performing flight physicals, and it is always disconcerting (mostly to the pilot, of course) when this diagnosis is made during a flight physical examination. As with other medical problems, there are 2 sides to this coin…that of one’s health, and that of one’s Medical Certificate. I would like to take this opportunity to describe briefly what diabetes is, why it is becoming an increasingly frequent problem, and what can be done about it….for one’s health, and one’s Medical.

There are basically 2 types of diabetes, insulin-dependent (Type I) and non-insulin dependent (Type II.) In order to understand the difference, bear with me a short review of the biology involved. This will help you understand how these diseases operate, how treatment works, and then how the FAA deals with it.

It is important to understand a couple basic premises. First, every cell in your body needs fuel, and that fuel is glucose and glucose only. Glucose is like avgas for your plane….without it, no work can be performed. It is the basic building block of all forms of carbohydrates, which are eventually broken down into glucose for each of your body’s cells to use. However, the cell cannot recognize glucose floating in the bloodstream by itself. It must be informed that it is available for use, and this signal is insulin. Each cell of our bodies has insulin receptors attached to it, and when insulin comes into contact with these receptors it activates them and signals to the cell that glucose is available. This action opens up the cell to glucose and brings it in, so that it can now be used by the cell for fuel. Without either insulin or these receptors, cells could literally be swimming in a sea of glucose and not know it!

Secondly, there are potential problems with insulin production, and there are potential problems with insulin receptors. This is where Type I and Type II diabetes differ. In insulin-dependent diabetics, the body (for whatever reason) has quit making sufficient amounts of insulin. Such a person can eat carbohydrates, break them down into glucose units, and yet the cells can starve because there isn’t enough insulin to tell them that glucose is right outside waiting to come in. Insulin is produced by the pancreas, and under normal circumstances the amount of insulin secreted exactly matches the amount of glucose rising in the blood stream. This occurs rapidly and from moment to moment.

Type I diabetics need to receive insulin in the form of injections (science has not yet perfected a form of insulin that one can swallow) and of course it is important to match the amount of insulin as closely as possible to the amount of carbohydrates ingested. Because it is difficult, if not impossible, to duplicate this exact and rapid matching of insulin to glucose levels in the blood with injections, insulin-dependent diabetics can have high and low swings of blood sugar. If too high too often, critical cells in blood vessels are injured and the long-lasting complications of diabetes will ensue: infections, loss of circulation, kidney disease, blindness, and early death. If too low, the brain can’t get the food it needs to remain conscious, and disorientation or fainting can result. If not quickly resuscitated with supplemental glucose, the hypoglycemia brain can have permanent damage, and the person can die.

Non-insulin dependant diabetes, on the other hand, results from receptor failure. If the cell’s insulin receptors do not work properly, more and more insulin is produced by the pancreas in response to rising blood sugars. Although these people can have very high levels of insulin in their bodies, their cells cannot recognize it, and therefore don’t respond by taking the glucose in. These people need to be treated with methods that increase the receptors’ sensitivity to insulin, so that they can “wake up” to the fact that there is sugar out there to be taken in. Here is where it gets interesting, just bear with me!

There are people who have a genetic predisposition to insulin receptor dysfunction or, in more common terms, insulin resistance. They need to be treated with careful attention to proper diet (limiting caloric intake) and perhaps medications that increase their receptors’ sensitivity to insulin. Once these receptors “wake up” they can again recognize the naturally secreted insulin and take in the glucose. Please understand that this is not a cure, but a treatment that will probably be lifelong.

On the other hand there are people who develop insulin receptor resistance because of obesity and sedentary lifestyle. It is a known fact that being overweight somehow interferes with the sensitivity of the insulin receptors, and that the fatter one gets, the more resistant these receptors become. These people can frequently get rid of their diabetes by losing weight and exercising, and getting down to a normal body mass index (between 18-25 % body fat.) So, knowing that obesity can directly cause diabetes, it is not surprising that this disease has become an epidemic in this country, as 60 % of Americans are now overweight. The treatment is simple….eat less and exercise more!

Note that nowhere in this article have I stated that sugar causes diabetes. It definitely does not. What causes diabetes is a complex interplay between one’s genetics and one’s lifestyle. The more genetic predisposition one has for developing diabetes the easier it is for an individual to develop it if he or she is overweight. Eventually it seems that most people who are obese develop problems with the internal signals for proper glucose metabolism. It should be noted that being obese shorten one’s lifespan in other ways such as increasing one’s risk of high blood pressure, cancer, physical injuries, and psychological problems such as depression.

There seem to be very few people who develop diabetes purely from genetic reasons or purely from bad lifestyle choices, as in most cases there is an interplay between both causes. Whatever mechanisms are involved in producing an individual’s diabetes, one can still improve one’s life and lifespan by getting regular exercise and keeping weight to normal, as this reduces the risk of all those other nasty problems mentioned in the previous paragraph.

So, how does an airman first get identified as having a problem with sugar metabolism on his or her flight physical? By having glucose in their urine on examination. Granted, even “normal” people can, under extreme circumstances, have glucose in their urine if they had ingested a HUGE amount of sugar just prior to their examination. But the emphasis is on HUGE. Under normal circumstances, there should not be any sugar in the urine, because the kidneys are able to handle normal sugar loads and prevent it from spilling over into the urine from the bloodstream. If an individual exceeds his or her kidney’s ability to handle this load by ingesting a very large amount of glucose, some glucose might end up in the urine. The question of whether or not such a person has diabetes can then be answered by a couple simple blood tests, such as measuring their blood sugar and their “glycosylated” hemoglobin. The blood sugar can determine the amount of glucose in the blood at the time it was drawn (but not where it has been or where it goes in relationship to a meal) and the glycosylated hemoglobin (also known as a hemoglobin A1C) can determine how high it has been in the past 2 months or so. The FAA of course has its limits of what it will accept, but for the purpose of this article I won’t go into that kind of detail.

OK, so what about your Medical Certificate? Basically, diabetes is one of the 15 disqualifying medical conditions that have been identified by the FAA. That doesn’t mean that one cannot fly! The FAA has several categories of Special Issuance for diabetics who are well-controlled, and here are the rules:

1.) For insulin dependent diabetics, only Class III Special Issuance is allowed. Because it is so difficult even with today’s technology for these diabetics to perfectly regulate their blood sugars, especially to avoid hypoglycemia, the FAA only allows certification for Class III. However, not every insulin dependant diabetic will get a favorable review by the FAA, only what I call the “cream of the crop” diabetics. These are people who have demonstrated excellent control of their diabetes, are meticulous in their insulin and dietary management, have no episodes of hypoglycemia, and have no other significant medical problems that would interfere with their disease management. The FAA also has rules about checking blood sugars prior and during flight, and prior to landing. It gets complicated, but seems to work OK. Currently there are about 300 or so such insulin-dependent diabetics flying in the USA…and nowhere else in the world are they granted this privilege!

2.) For non-insulin dependent diabetics who are able to control their blood sugar by diet and exercise without medications, they are considered eligible for all classes of medical certificates, provided they have no evidence of associated disqualifying heart, circulatory, kidney, neurological, or eye diseases or complications. They do not need any additional specific testing unless it is indicated by their history or examination. No Special Issuance is required as long as they remain purely diet and exercise controlled.

3.) Airman with a diagnosis of diabetes controlled by use of an oral medication may be considered for Special Issuance for all three classes of Medical Certification. Per the FAA protocol, “following initiation of such oral medication, a minimum 60-day period must elapse prior to certification to assure stabilization, adequate control, and the absence of side effects or complications from the medication.” It is important to note that the FAA has to make the initial certification decision, not the AME. Recertification decisions will be made on the basis of reports from the treating physician, and these reports basically have to have the same information as the initial report. Usually for airman under good control, the FAA will issue a 6 -year Special Issuance Authorization, with each Medical Certificate being valid for only one year at a time. As long as the Special Issuance Authorization is in effect and the annual reports from the treating physician are favorable, the AME may issue a time-limited certificate of one year (for all Classes), while future medicals must be based on continuation of good control. This information is forwarded to the FAA and reviewed for correct handling by the AME. Recertification by the FAA occurs when the Special Issuance Authorization has expired, or the airman’s diabetes management has changed.

To learn more about Special Issuance processes, even for other disqualifying conditions other than diabetes, there are a variety of good web sites available to you:

FAA: www.FAA.gov and go to Aerospace Medicine under Quickfind, and poke around. It’s a little cumbersome, but you can find the information.

AOPA: www.aopa.org, and click on “medical”

ALPA Aeromedical (this is the web site for the doctors for the Airline Pilot Association, who call themselves the Virtual Flight Surgeons here…and I believe this is the best web site for all aeromedical problems) at www.aviationmedicine.com

Or you are welcome to contact me directly if you prefer. I can be reached at:

Aviation Medicine Services of Alaska
5011 Spenard Rd. #102
Anchorage, AK 9957
(907) 245-4359
email: This email address is being protected from spambots. You need JavaScript enabled to view it.
web site: www.AirSpaceDoc.com

So, it is obvious that most cases of diabetes are eligible to fly under Special Issuance, but also clear that it requires commitment by the airman to manage this very serious health problem. Remember, the priority is to your health, and your Medical Certificate will follow you wherever you go!

Last week, one of my “regulars” came in for his Class I flight physical. I was glad to see him, as I knew him to be young and healthy. It was a busy Friday and I was already a bit behind. I was looking forward to an “easy” case to catch up. However, this was not to be. To both our surprise, his blood pressure was very high! I was surprised because his past pressures, as recently as 6 months ago, had always been nice and low. He was surprised because he couldn’t think of anything that had happened to cause this, and besides, he felt perfectly fine. I questioned him about the usual: family history, severe stress, new medications, espresso coffee ingestion, over-the-counter cold medications, diet pills, and the like. He denied everything. His pressure was so high that I was considering sending him to the emergency room.

Finally he told me that the only thing different since his last flight physical was a new vitamin product which he had been taking for the last couple months. Because it was “just vitamins” he didn’t think to mention it. Further questioning revealed that these were not “just vitamins,” as there were additional ingredients to “enhance male energy.” He had no idea what all was in this product, but because it was “organic and natural” and from a reputable company, he assumed it was perfectly safe.

I asked him to stop taking this product and that he continue to measure his blood pressure over the weekend. He was to recheck with me on Monday, and bring the container so that I could read the ingredients. Although still not down to normal, his pressure was much improved from a couple days later. Of great relief to him, it was now at least low enough to pass FAA standards.

So, what was in this seemingly harmless concoction from a very reputable and nationally known company? Other than the standard vitamins (which one can purchase for pennies a day) this expensive product contained the following ingredients, among others:

Damiana (for sexual enhancement)

Gingko Biloba (for mental enhancement)

DHEA, or dehydroepiandrosterone (for muscle building)

Ginseng (for general energy)

Ephedra, also known as Huang Ma (for energy and heightened metabolism)

I am not sure if Damiana and Gingko Biloba have effects on blood pressure, but certainly DHEA, Ginseng and ephedra can. DHEA, which is a type of anabolic steroid, can also be dangerous to the kidneys. This is an ingredient found in many body-building products. Gingko Biloba and Ginseng, although quite popular within the natural supplement community, have not been found to be effective (more than placebo) in controlled scientific studies. Ephedra (Huang Ma) on the other hand, is a form of “speed” and is related to substances such as pseudoephedrine, which is found in over-the-counter decongestants and is a main ingredient for making methamphetamine and diet pills. These chemicals can have profoundly deleterious effects on the cardiovascular system by provoking hypertension, rapid heart rates, and narrowing of important small blood vessels….such as in the heart and brain. Additionally they can produce adverse psychological symptoms such as anxiety and even panic attacks. In healthy younger people these effects might be well tolerated, but in older individuals with underlying circulatory disease these products can precipitate heart attacks and strokes.

Plants produce thousands, perhaps millions of different chemicals that are used a variety of purposes. Biologists have only scratched the surface in learning about these compounds, but many have been known to mankind for thousands of years for their medicinal purposes. Some medications in use today are direct derivatives of these substances, and are indispensable in treating acute and chronic diseases. These drugs are purified versions of plant extracts, and are prepared under carefully controlled conditions ensuring accurate concentrations and purity. Some can be purchased over-the-counter (such as aspirin) but most require a doctor’s prescription. That is not the case in the health food industry. In the USA, powerful interest groups have prevented these “food supplements” from being regulated by the Food and Drug Administration. This has created a totally unregulated industry, meaning that there is no governmental agency ensuring that these products are actually what they are labeled to be. The purity and dosage of the products are not assured.

The purpose of this column is not to describe in detail all the possible side-effects of various health food substances on the market, but rather to alert the reader to the potential health hazards in this unregulated industry. The science behind the claims these companies make is usually very weak, and relies on testimonials rather than on properly conducted double-blind studies. The buyer must be aware, as there is no regulatory agency overseeing quality inspections or monitoring.

The FAA requires pilots to disclose the prescription and non-prescription medications they take on the medical certificate application 8500-8. However, because the FDA classifies these substances as food supplements and not as medications, the pilot is not required to disclose these products to the FAA. This further strengthens the fallacy in many minds that these products are safe.

So if you are taking more than just appropriate vitamins, please make sure that you follow the primary rule of healers, which is TO DO NO HARM. Make sure you really need this stuff, that you are not just succumbing to media hype feeding on your fears of aging. Even if the evidence for its benefit is weak, make sure that at least it is not going to hurt you……or your medical!

Ophthalmologists have come a long way in the past 20 years since they began reshaping corneas for improving vision. Initially this was performed by actually cutting slices into the cornea by hand, like spokes on a wheel, in a procedure known as radial keratotomy (RK). Now much more highly sophisticated technical equipment is used, such as lasers, making the procedures easier on both patient and eye doctor, as well as safer and more precise. Before all pilots who are getting good vision by relying on harmless pieces of curved glass start lining up for these procedures, they should put these surgeries into perspective, both from the point of view of their general visual health as well as their FAA medical certificates.

Briefly, the concept of refractive surgery involves changing the shape of the interface of the cornea and the outside air. If you remember your high school physics, you will recall that light bends when it travels from one density to another. This is what happens when you look at your feet while standing in a swimming pool…your legs look bent. When light traveling through air meets the curved surface of the cornea (water density), the shape of the cornea determines where in the back or your eyeball it will focus, relative to the length of your eyeball. In people with perfect vision, that point occurs on a small spot on the retina, and minor adjustments are made by the lens to fine-tune that focus for the differences in distances of the object being viewed. Most of us have corneas that are not perfectly shaped. Some corneas are too flat, resulting in far-sightedness (hyperopia) while others are too pointy, causing near-sightedness (myopia). Others are curved irregularly, causing a condition called astigmatism. It should be noted that the age-related problem of close-up vision difficulties (called presbyopia) has nothing to do with the shape of the cornea, as it is the lens that becomes less pliable over time. This condition therefore is not treatable by refractive surgery, unless one considers having one eye corrected for near vision and the other for distant vision. More on that later.

Nowadays, the 2 most commonly offered surgeries are photorefractive keratectomy (PRK) and laser assisted in situ keratomileusis (LASIK). The former involves literally vaporizing the outermost layer of corneal cells with a laser, the latter involves slicing a thin flap (but still attached by a hinge piece) off the central cornea and then reshaping the layer of cornea underneath with a laser. When the desired shape is obtained, the flap is placed back onto the cornea and allowed to heal in place. PRK is done less than LASIK these days, as the latter is the newer technique and offers a number of advantages over the older procedure. For example, the “recovery time”(which means time one can see well enough to go back to work in a regular job, not necessarily to return to flying…will go over that later) can be as short as 2-3 days…in fact some eye doctors feel comfortable enough to do both eyes at the same time.

It must be pointed out that as in any surgical procedure, complications can happen to anyone, and for a pilot, even some of the more minor complications can interfere with qualifying for a medical certificate.

Occasionally potential vision-threatening complications occur, such as infection, development of haze in the vision, scarring, night glare, perforation of the eye, and prolonged post-operative steroid drop use which can result in cataracts or glaucoma. Less devastating but problematic complications of LASIK include detachment or movement of the flap resulting in double vision, growth of corneal tissue into the flap, bleeding into the white part of the eye, and technical problems associated with the instruments. Also somewhat common, but usually temporary, are problems with mild irritation, dryness, sensitivity to bright lights, and tearing.

In order to have the best results from LASIK, certain selection criteria should be kept in mind. First and foremost is the health of the patient and their eyes. People with corneal diseases, collagen vascular diseases, pregnancy, or side effects from steroid medications should not undergo these procedures. Patients should be older than 18 years of age, and should have “stable” refractive errors to begin with. Without giving you the

meaningless formula, this means people who can be expected to have good result with refractive surgery, not individuals whose corneas are so severely misshapen that they cannot obtain reasonable results. Pupil size must be small enough that when in the dark, the edge of the pupil does not expand beyond the edge of the corneal flap, resulting in a condition where night glare would occur. Most importantly, the patient should have realistic expectations. Although these techniques have become extremely precise these past few years, no one should undergo these procedures with the expectation that they will obtain perfect vision. Some folks can only get improvement, and may still need to rely on glasses for perfection. It is also important to reiterate that the loss of clear close-up vision that comes with age cannot be altered by surgery, and that such patients undergoing this procedure may still need to wear reading glasses.

After surgery, one should not rub the eyes, and contact sports should be avoided at least 6 months, as it might dislodge the healing flap. For the pilot it is also important to know the FAA requirements to maintain their medical certification.

To date, because of the slight increased risk that a hard blow to the head could cause the post operative cornea to rupture, military pilots are not allowed to have refractive surgery done, either before or during their flying career. Corneal mapping is generally done on military applicant pilots to exclude those that have had these procedures, although the military is currently researching the feasibility of changing that rule. Most airlines do not have any such limitations as long as the pilot meets acceptable FAA standards. Let me now walk you through those standards for civilian airman, both private and commercial, because the guidelines are the same, and a waiver is no longer required.

The FAA’s requirements are based on 2 principles, the first being that the eye surgeon verifies complete healing has taken place and that vision has fully stabilized. For LASIK, visual stabilization usually occurs within 3 months, and residual night glare can be expected to diminish within 6 months. In some people, this can occur much more rapidly. The ophthalmologist needs to fill out an FAA form called “Report of Eye Evaluation” Form 8500-7, which must be submitted to the FAA. This can be done directly or through your AME. Secondly, as in any other situation, your vision must meet the standards for the class of medical certification requested, whether with or without corrective lenses. That part has not changed.

There is one interesting new opportunity worth mentioning for those of us who wear bifocals. Near the beginning of this article it was stated that corneal surgery is not useful to correct presbyopia, which is the situation where near vision is adversely affected due to the aging of the lens. For this common condition, some ophthalmologists are recommending surgery to correct one eye for near vision and the other for distant vision, rendering the person essentially monocular. In other words, one would use one eye to visualize objects far away, and the other for close vision. This same effect can be achieved with contact lenses, a situation which the FAA does not allow because it destroys depth perception. Despite this fact, the FAA does now allow this surgical procedure to be done on pilots. The reasoning is that, in contrast to contact lenses which are removed regularly, the surgery makes this a continuous and permanent condition and thereby allows the person to eventually learn depth perception by experience, just as an individual who physically loses one eye learns depth perception by integrating other visual clues. The FAA requires the pilot who has this done to use glasses or contacts that correct both eyes for near and distant vision while flying for six month period afterward, in order to allow time for this adjustment to occur. Thereafter, the pilot may apply for a Statement of Demonstrated Ability (SODA) and undergo a medical flight test with an FAA examiner in order to get the corrective lenses restriction removed from his or her medical certificate.

Now, with all the above information, is refractive surgery right for you? There are a variety of individual questions that must be answered, and they are all different for each and every pilot. Consideration should be given to the fact that most insurance companies do not cover this procedure, and can cost up to $2,500 per eye. Also, one must think about the sick-leave from work. In a non-flying job, this may be less of a problem, unless complications are encountered. In a flying-related job, consideration must be made that it make take several months for vision to stabilize enough for FAA approval. I frequently advise airline pilots to refrain from refractive surgery until they retire, as complications may permanently interfere with their careers. Unless the use of glasses or contacts presents a severe annoyance in the cockpit, or uncorrected vision is so terrible that suddenly being without one’s corrective lenses might produce a safety hazard, this surgery can be considered cosmetic and might best be done when one’s livelihood no longer depends on passing the FAA medical examination.

One final point…whether pilot or not, one should never be talked into this kind of surgery by an aggressive eye doctor. If you really are interested in this, carefully choose your ophthalmologist. Find out who performs the most procedures, has done them for the longest time, and who has had the best results in your community. Speak with former patients, and never hesitate to get second opinions from other ophthalmologists.

It is a common misconception that over-the-counter (OTC) drugs are not only safe, but are also FAA approved to use while on flight status. After all, if a medication were harmful, wouldn’t it require a prescription? Not necessarily so! Many OTC drugs can actually be quite dangerous, especially when used inappropriately in relation to flying. In my practice, I find that pilots frequently misuse certain OTC medications, not understanding the FAA restrictions, and more importantly, the potential dangers to flight safety. Some of these medications are marketed for both allergies and sleeping aides, so you can be sure there are not only FAA rules that go with their use, but more importantly, safety principles.

In the OTC world, the most commonly sold anti-allergy medications are made from “first-generation” antihistamines, such as diphenhydramine and chlorpheniramine. They help reduce the unpleasant symptoms of itching, watery eyes, runny noses, sneezing, and hives caused by seasonal or environmental allergies. Diphenhydramine (also known by the brand name Benadryl) can be a life-saving drug when used to treat severe allergic reactions, as can occur from bee stings or food allergies in highly sensitized individuals. However, these antihistamines also produce significant drowsiness in most people, and because adverse effects on mental functioning can last even longer than perceived drowsiness, the FAA warns that pilots should ground themselves for at least 5 times the drug’s half-life (or 5 times the maximum dosage interval if half-life information is not available).  For diphenhydramine, that means 60 hours!

Because these antihistamines are found in many OTC cough and cold remedies, pilots often take them inadvertently. An airman should always carefully review the ingredients of such multi-symptom formulas, making sure that they do not include any compounds to control itching, sneezing, or to induce sleep. Decongestants (pseudoephedrine) are generally OK to use during flight status, but first-generation antihistamines are not!

After several years as prescription medications, a few “second generation” antihistamines are now available over the counter. The nonsedating antihistamines loratidine (Claritin), desloratidine (Clarinex) and Fexofenadine (Allegra) may be used while flying if, after an adequate initial trial period, symptoms are controlled without adverse side effects. There are others of this category available by prescription, or OTC but not all are currently FAA approved.  Just because your personal physician prescribes it, doesn’t mean that the FAA considers it safe for flight. For example, cetirizine (Zyrtec) is not.

Whether OTC or prescription, the FAA requires waiting periods after taking medications that produce drowsiness. These waiting periods are based on how long the drug takes to be eliminated from the body – defined as “half life” – which is the time that half the drug is metabolized and eliminated by the body.  The longer the half-life, the longer the potential side effects. If the half-life is not available, the alternative is to determine the waiting period based on how often the drug is to be taken – or its dosing interval. The longer the half-life, the further apart the dosing interval.

According to the FAA, sedating medications should not be taken until:

• • At least five maximal dosing intervals have passed. For example, if the medication is taken every 4-6 hours, wait 30 hours (5×6) after the last dose to fly, or,
• • At least five times the maximum terminal elimination half-life has passed. For example, if the medication half-life is 6-8 hours, wait 40 hours (5×8) after the last dose to fly.
  • • At least five maximal dosing intervals* have passed. For example, if the medication is taken every 4-6 hours, wait 30 hours (5×6) after the last dose to fly, or,
  • • At least five times the maximum terminal elimination half-life has passed. For example, if the medication half-life* is 6-8 hours, wait 40 hours (5×8) after the last dose to fly.

Now, let’s get to the category of sleeping medications. In the OTC world, the drowsiness produced by these first-generation antihistamines is capitalized upon, and used as sleeping medications. When marketed as such, diphenhydramine is found in formulas such as Tylenol PM, Sominex, Excedrin PM, and the like. Not knowing this, pilots will often take these OTC sleep aides in ways that are not safe and certainly not FAA approved. Long-haul pilots who take these medications in an attempt to counteract jet lag might not realize that they will begin another flight before the required 60 hour waiting period is over. Cockpit crew members with heavy schedules and short layovers sometimes find themselves taking these antihistamines in order to get to sleep quickly for an early wake-up call, again before enough time has lapsed for the side effects to wear off.

It is noteworthy to mention that diphenhydramine is one of the most common OTC drugs found in the tissues of pilots involved in fatal airplane accidents. There is a reason for those warning labels recommending against operating dangerous machinery while “under the influence“!

There is another category of physiologically active compounds that are neither prescriptions nor OTC drugs. These are the dietary supplements; some are reported to help reduce sleep problems, such as melatonin. The FAA generally allows airmen to use any of these supplements if they do not suffer adverse side effects from them. However, claims about these dietary supplements’ benefits in treating insomnia and “jet lag” are often overstated, and have not been substantiated in scientific double-blind studies. Some individuals actually have significant side effects from these “natural” supplements, and in the case of melatonin can even produce nightmares and other sleep disturbances. There is also concern among some scientists that melatonin might adversely affect other basic body clocks, such as reproductive cycles in women, particularly because the dosages in these pills can create concentrations in body tissues much higher than what occurs naturally. Additionally, since the Food and Drug Administration does not regulate food supplements, it is not possible to ensure the purity and dosage of these substances. Buyer, beware!

Then there is alcohol. Aside from the 8 hour “bottle to throttle” rule, alcohol is not, in fact, a decent sleep-inducing chemical. It actually interferes with natural sleep cycles and impairs the brain’s ability to refresh itself. There are also some commonly prescribed sleep medications that are not allowed by the FAA, such as Halcion due to its long half-life and potentially addictive tendencies.

So, having said all this what can a pilot use to help get to sleep on those layovers, or to help re-adjust to a normal cycle when back home?

For the past couple years, the FAA has approved the use of one prescription sleep medication, Ambien (zolpidem), by virtue of its short half-life (2.5 hours) and safe side-effect profile. Its minimum “no fly” waiting time is 24 hours. More recently, the FAA has approved another ultra short-acting sleep aide that one may fly as soon as 6 hours after ingestion – Sonata.  Here is a chart showing the waiting times of various popular sleep aides.

As can be expected, there are some FAA regulations that pilots must be aware of when using these medications. First of all, they must wait the minimum time required before flying. Secondly, they should not be used more than once or twice a week in order to avoid habituation. It should go without saying that there are always a few individuals who will have unusual and unanticipated side effects to any medication, so a pilot should always “ground test” any new drug first during a few days that he or she will not be flying, in order to assure that unanticipated adverse effects will not occur. This rule actually applies to all OTC medications, “natural” supplements and prescriptions, which a pilot has never used before, as the time to discover unexpected side effects should not be in the cockpit! Bear in mind that no sleeping medications should be used on a regular basis to treat chronic insomnia, which is a medical condition where an individual has chronic sleep disturbance. In order to avoid habituation, these drugs should only be used intermittently for those circumstances where sleep is difficult to attain because of disrupted schedules.

Having said all this, none of the medications discussed in this article will show up on a DOT drug screen. For safety sake, you, the pilot, must be the judge!

There is some evidence that a moderate intake of alcohol offers some health benefits, although it is also a well-established fact that too much of a good thing, or a good thing at a bad time can be quite dangerous. Alcohol is a major factor in motor vehicle deaths, and still is a significant causative factor in aviation deaths.

There are two FAR’s that are important to know when it comes to drinking and flying. Most pilots are aware of the “8 hour” rule, that is, 8 hours from bottle to throttle, although many airlines have a more stringent 12 hour time limit. Most pilots do not know of the 0.04% FAR, which prohibits flying an aircraft with a blood alcohol concentration (BAC) of 0.04% or higher.

Let’s talk a bit about the physiology of alcohol metabolism, in order to understand these 2 different FAR’s, and what they mean to the pilot. The first one is quite clear. The FAA prohibits the ingestion of any alcohol within 8 hours of flying as a pilot crew member, be it general or commercial aviation. For most of us who are not heavy and regular drinkers, if we follow the 8 hours rule, we would assume that we should not generally be busting the 0.04% rule. However, because our bodies eliminate alcohol at a constant rate, it is quite possible to ingest enough alcohol, follow the 8 hour rule, and still be over the 0.04% limit. In comparison, most states set this limit for driving under the influence (DUI) at a higher level, generally about 0.08%.

The BAC at any given time depends mostly on the size (and to a lesser degree the sex)of the person, the amount ingested, and the amount of time passed since ingestion. It has nothing to do with the alcohol experience of the person, although habituation certainly leads to tolerance, meaning that higher BAC’s can be tolerated by the individual.

Pure alcohol is metabolized at a rate of about 0.015 mg% per hour. The concentration of a unit of ingested alcohol in a person depends on the size of that person, but the hourly rate of elimination is the same, regardless of size of the individual. Since a standard serving of any alcoholic beverage contains roughly the same amount of alcohol, the following formula can be used to approximate the BAC at any given time:

(Body weight per drink x number of drinks) – (elimination rate x number of hours since last drink)

To make this calculation, the following table shows the figures for the first variable (Body weight per drink) in the formula, for 3 different sizes of individuals:

0.04% per drink @110# 0.03% per drink @155# 0.02% per drink @200#

To illustrate how this is calculated, let’s take the middle person who weighs 155 pounds. A standard alcoholic beverage would result in a BAC immediately after consumption of 0.03%. If that person drank 6 drinks rather quickly, 8 hours later his BAC could be estimated by plugging in the numbers and doing the arithmetic like this:

(0.03 x 6) – (0.015 x 8) = 0.06%

Note that this exceeds the 0.04% rule!

From this discussion, it is easy to figure out that one could still be legally intoxicated even while complying with the 8 hour rule. Furthermore, there are important issues pertaining to alcohol abuse and alcoholism as it relates not only to flying, but to one’s general health.

While many of us have had occasion to overindulge and suffered the unpleasant, but rather short term consequences of that behavior, that is quite different from what is considered alcoholism. There are a variety of definitions of this disease, but in general they all contain these 2 important elements: that the need to drink becomes harmful to one’s relationships, and it adversely affects one’s activities of daily living, such as job performance. This frequently comes to light with behavior such as family quarrels, loss of reliability at work, and an accumulation of DUI’s. Since so much of one’s time and emotional energy is spent on working toward getting that next drink, the alcoholic’s judgment is impaired even when sober. Additionally, chronic alcoholism injures not only liver and heart tissue, but adversely affects the brain, and can therefore cause permanent cognitive impairment even long after sobriety is obtained.

Since it is not common for an alcoholic pilot to self report their problem to society, the FAA has 2 further regulations that are intended to identify pilots with potential alcohol problems. One requires that a pilot who is found guilty of a DUI report this to the FAA Civil Aviation Security within 60 days of this action. The other one is a mandatory report of DUI on their next Airman Medical Examination. It should be noted that when you sign this document, not only are you certifying your truthfulness but you are also authorizing the FAA to compare your statements with the National Driver Registry for verification. It should be emphasized here that the FAA does not consider a person to be an alcohol abuser with one DUI. However, the FAA can automatically revoke, suspend, or deny a medical certificate if there have been two or more DUI’s within a three year period. It should be obvious that it is by far more important to honestly document even one DUI action as hiding it would only increase the suspicion of alcohol abuse. Furthermore, any falsification of information on the FAA Form 8500 (the Airman Medical Examination form)can subject an individual to criminal penalties of a fine up to $250,000 or imprisonment for not more than five years, or both.

In the General Aviation world, the FAA will consider granting a Class III or even a Class II Medical Certificate to a pilot who has successfully undergone alcohol treatment. This usually requires some sort of recognized treatment center, either inpatient or outpatient, depending on the circumstances, and strong evidence of sobriety for a period of 2 years. This can include documentation of attendance of AA meetings, letters from employers or other reputable individuals who know the pilot well, or at best a letter from the treating counselor indicating successful treatment. The FAA takes a more difficult stance with individuals who relapse.

For professional Class I pilots, there is a special program developed several years ago called HIMS, which stands for Human Intervention and Motivation Study. This is an extraordinary program that brings together the FAA, ALPA (Airline Pilots Association) and the management sector of the airline industry. It sets the rules for bringing back successfully treated alcoholic pilots to the cockpit, and requires strict adherence to a sobriety program. In general, the pilot must undergo a 4week inpatient treatment program, and prove sobriety through a rigorous process that includes regular AA meetings, involvement with a peer group, regularly scheduled meetings with their medical sponsor (usually their AME)as well as a representative from their airline, and regular urine tests. They can be returned to the cockpit as soon as 3 months if it is felt that they are successful, but must remain in the program for monitoring for a minimum of 3 years. These programs have been shown to be highly successful, as these pilots are usually highly motivated to keep their jobs.