Many people are now interested in anti-aging therapies. One of the elements of anti-aging medicine is the restoration of growth hormone, using pharmaceutical injectable growth hormone. The following information is from the book "Resetting the Clock" by Elmer Cranton M.D. It is a great overview for anyone interested in Anti-aging therapy using injectable growth hormone. The book can be ordered by visiting Dr. Cranton’s site at www.bestvitamins.com/BestVitamins/resettin.htm

I heard from a doctor in Texas who treated his ninety-five-year-old mother with HGH. Over the previous year she had grown exceedingly weak and despondent and had finally become bedridden. The doctor couldn't find any precise constitutional reason for her state; she simply didn't seem to have the strength to live anymore. Within two months of starting replacement doses of HGH, his mom was walking again. Within three months she was happy to be alive. If the illness that doctor was treating wasn't aging, I don't know what to call it.

This is interesting because, certain as I am that human growth hormone will be increasingly used in coming decades to treat such medical conditions as heart disease and Alzheimer's, I'm well aware that its use in the control of aging is another matter.

Our own Food and Drug Administration is very specific about the fact that it does not regard aging as an illness. A reasonable view to them, no doubt, even if many gerontologists tend toward the opposite opinion and speak of aging as the ultimate illness. Unfortunately in such disputes there is a good deal more at stake than verbal hairsplitting. The FDA's choice of a definition is done with a purpose. If aging is no illness, then clearly any medicine created for the purpose of slowing or reversing aging is not medically sound and not appropriate for government approval. And drug companies are well aware of this. They know that if they wish to have a drug approved, they must demonstrate its effectiveness against a "real" illness—a definite "disease." Even when applying for approval to treat a recognized disease, such as Alzheimer's, arthritis, or Parkinson's, aging need not—and should not—be mentioned in their submission to the FDA.

Click here for Cautions about So-called or Compounded Generic HGH

Thus the development of HGH as an anti-aging therapy is going to be left largely to the initiative of doctors and patients. I believe this movement will ultimately be consumer driven by aging baby boomers. That is what's occurring, still slowly but more and more noticeably, nationwide. This fundamentally unusual and significantly unregulated situation is advantageous in one sense. As the price comes down, which is slowly happening, I predict that the use of growth hormone to reverse and slow aging will proceed with an astonishing speed that would never occur in the normal development of a significant new medical treatment. The same situation is disadvantageous in that quicker development implies less testing to determine side effects and hazards. And clearly nothing as potent as human growth hormone can be entirely without some potential risk.

Let’s look at any potential risks involved in using low, replacement doses of HGH. Then we'll consider who's making growth hormone, how it's being made, how reliable the suppliers are, how it's being brought into this country, and how you'll go about getting it, should you and your physician decide this is the therapy for you. Finally, we'll take a peek into the future.

THE PRUDENT APPROACH

I have two strong opinions about growth hormone, which I hold with equal vehemence. One is that restoration of youthful levels of HGH is a potentially powerful and beneficial aid to a vital long life. The other is that this is not a substance that an individual man or woman should consider taking independently of the advice and guidance of a knowledgeable health care practitioner.

It is true that the relative safety and infrequency of side effects caused by growth hormone is genuinely reassuring; it can only be explained by the fact that HGH is a natural product of our own endocrine glands and safe and prudent treatment involves simply restoring it to the levels that were present, necessary, and well tolerated in young adulthood. That this is the true explanation for its impressive safety record receives support from the fact that almost all recorded adverse effects have occurred when the hormone is given at doses significantly higher than what the human body normally produces in its youthful prime.

In replacing hormones it has become increasingly clear that we are wise to follow nature. In medicine this is called giving physiological doses—amounts that a healthy, youthful body naturally produces. The opposite approach is to give pharmacological doses—amounts in excess of what any healthy human body would produce for itself. Unless a strong series of medical studies eventually shows that some compelling advantage can be had from such an approach, I definitely advise against pharmacological doses of HGH. The commonly held belief that if a little is good, more is better, does not apply.

The Range of Side Effects

Now let's look at every conceivable side effect that the several dozen growth hormone studies conducted so far have identified.

First off, I would like to mention, only in order to dismiss, one grotesque and fearful side effect of overdosage. In the early days of giving HGH, there was some apprehension that acromegaly might result. Acromegaly is a rare disease of giantism or abnormal bone growth that occurs when a tumor in the pituitary gland secretes vastly excessive levels of growth hormone over a long period. A childhood occurrence of acromegaly causes giantism, as in the case of Robert Wadlow, the tallest documented human, who reached eight feet eleven inches before his early death. In cases where the excessive secretion of growth hormone occurs after adulthood, increase in overall body size occurs somewhat differently. There is little increase in height and only limited growth in the bones of the extremities and of the face (causing facial deformity). Fortunately, acromegaly has never occurred in a planned program of growth hormone replacement, even at doses far higher than I would recommend.

The side effects that have been reported, usually with excessive doses, include:

• edema (water retention)
• occasional carpal tunnel syndrome
• slightly increased blood pressure
• slightly increased blood glucose levels

When growth hormone is supplemented at too high a level, these are, indeed, very natural consequences of its action. Consider edema. It is a basic medical maxim that body water content decreases with age. Tissues become slightly dehydrated. In fact, by the time young men and women become senior citizens, the percentage of water by weight in their bodies has declined by 10 percent. When HGH levels are brought up, tissue water content is restored to a younger level. I have not seen abnormal edema in any of my own growth hormone patients, merely that that skin texture improves with more normal hydration.

The important point to note is that when a sudden increase in HGH has resulted in symptomatic edema, this has only occurred when patients were given doses higher than the body would naturally produce. In the early studies of growth hormone, the doctors conducting the experiments were not at all certain what a normal dose would be. Even Daniel Rudman, in his famous 1990 study of HGH administered to elderly men, used sixteen units of HGH weekly. That's three to four times the amount needed to bring substantial improvement in the average sixty-five-year-old. In other words, I and most physicians prescribing HGH replacement today seldom prescribe more than seven units a week, and as little as four units week can be quite beneficial (one unit daily for four days per week). As it happened, none of Rudman's patients suffered significant edema (although there was one case of carpal tunnel syndrome). In other experimental studies using even higher dosages, edema has been a problem. If you look at the dosages in the table below, you can see the levels of HGH administered in eleven well-regarded studies of human growth hormone. At the higher doses, some edema was noted.

My advice to patients is first, of course, to supplement at a safe physiological dose, which is usually one unit four units per week. When a patient already has a problem with water retention, I watch his or her progress more closely. So far, problems have not occurred. If they did, I would naturally lower the dose or stop for a while, and then follow the patient closely to see if the problem gradually abated. I believe that the body soon adjusts to a more normal level of HGH. Patients who required diuretics (water pills) for a valid medical reason before beginning HGH will naturally need to continue them afterward.

Any significant increase in fluid retention raises blood pressure, and this is undoubtedly the reason why hypertensive patients have experienced blood pressure increases in some studies of the hormone. Nevertheless, if a person's hypertension is being controlled by diet or medication, I do not regard high blood pressure as a reason for not enjoying all the other major health advantages supplied by HGH.

Dosages of HGH in Eleven Major Studies of Human Growth Hormone

Once again, problems do not appear to arise when a person is taking a physiological dose—four to seven units per weeky—and wisdom counsels close consultation with a knowledgeable health care practitioner.

Carpal Tunnel Syndrome

The side effect most commonly seen in studies using large doses of human growth hormone is carpal tunnel syndrome. The carpal tunnel is a channel under the ligament crossing the front of your wrist through which major nerves pass to your hand. Pressure on those nerves can cause numbness, tingling, or weakness in the hand. This is a fairly common syndrome, especially in middle age and especially in women, not infrequently among people who spend a good deal of time working at a typewriter or computer keyboard and who suffer the effects of what has been dubbed "repetitive motion injury." The effects can be fairly unpleasant. Supplemental multi-vitamins, especially containing B6 (pyridoxine), may help or prevent this condition. Vitamin deficiency may be one cause.

Increases in levels of growth hormone speed tissue repair and protein synthesis in the body. This can create a greater demand for all nutrients, which may therefore aggravate any preexisting vitamin deficiency. If one adds to this two other effects that HGH may cause, namely increase in body water content and slight increases in the bone mass of the forearm and wrist, it's easy to see that HGH could trigger carpal tunnel syndrome if it was on the verge of occurring anyway. Rehydrated tissues can bulk back to normal within a carpal tunnel that was already narrowing with age. Both those effects, incidentally—increased hydration and stronger bones—are beneficial to the body as a whole.

I believe from my own experience and that of others that an aggravation or sudden onset of carpal tunnel syndrome after the commencement of growth hormone supplementation is going to be rare at the doses we currently use for anti-aging. Your health care practitioner should be aware of the possibility, however, and, if you already have a tendency toward carpal tunnel syndrome, he or she should take you into a supplement program that includes a spectrum of vitamins, minerals, and trace elements, including an insurance dose of B6.

It is important to also consider overall nutritional status. As tissue repair, healing, and cell replacement are speeded up by growth hormone replacement, the need for nutrients of all types also increases. Protein intake must be adequate to build up new tissues. Vitamins, minerals, and trace elements are all utilized in higher amounts as the metabolic rate returns to normal and cells are replaced and repaired. If the body is deficient or borderline in essential nutrients, an increase in cell growth can aggravate or create deficiencies that might not have been apparent otherwise. It is certainly wise to seek out a health care practitioner skilled in clinical nutrition and preventive medicine to help you manage your use of growth hormone therapy. Elsewhere on the Internet website I’ve outlined a typical program of diet and nutritional supplementation to go along with anti-aging hormones.

If you improve your nutritional status as you begin hormone replacement therapy, you will be far likelier to receive significant benefits and be better protected against side effects. I have observed that regular exercise, even just a brisk walk several times per week, will also increase benefits.

Risky for Diabetics ?

Once again the major consideration seems to be dosage. Growth hormone—administered in amounts considerably higher than necessary for reaching a young person's levels—has been shown to raise blood-sugar levels by antagonizing insulin. But in normal clinical practice, my own and that of many other physicians, increases in blood-sugar levels are miniscule to nonexistent. From a practical point of view therefore, growth hormone replacement ought to pose no sort of threat to people with diabetes or borderline diabetes. As with all administration of growth hormone, it is essential that individuals consult their health care practitioners, undergo lab tests, and tailor their anti-aging health plans to the requirements of their bodies.

What About Cancer?

Since growth hormone stimulates the growth of many different sorts of tissues, there has been speculation that it might increase the risk of cancer. All the evidence so far would indicate that HGH is not a risk factor. One published report of growth hormone research stated that in 16,604 person-years of treatment—a person- year is one person receiving a therapy for one year—there was no increase in the reported levels of cancer.

An even more convincing indicator that cancer risk from HGH is low, if it exists at all, is the overall experience of growth hormone administration to growth-deficient children over the course of the past twenty years. During this period tens of thousands of children have received growth hormone for periods as long as ten consecutive years. Recent reviews have shown that the incidence of leukemia and lymphoma, the most common pediatric malignancies, did not increase.

A smaller study was done in England on young brain-tumor patients.2 Because the radiation given in brain cancer therapy often damages the pituitary gland, a significant percentage of these patients are supplemented with growth hormone in the years following their treatment. The records kept by the British physicians showed that among 207 young brain-tumor patients, the individuals who later received growth hormone did not have any higher rate of tumor recurrence than those who did not receive HGH.

A more recent study in 2004 was reported by Mark L. Hartman, M.D., at the 12th International Congress of Endocrinology. A group of 2,429 patients was followed for more than years. 1,988 patients were treated with injectable human growth hormone (rHGH) replacement. They were compared to 441 similar patients who did not receive HGH. Statistical analysis did not reveal any significant difference in tumor growth, cancer or any other adverse events between the treated and untreated groups.

At one time there was a suspicion that HGH-related IGF-1 correlated with prostate cancer. Dr. L. Cass Terry published strong evidence that blood IGF1 levels have no relationship with PSA levels or prostate cancer. He measured IGF-1 from 749 men receiving HGH replacement therapy and compared them with a control group of 544 men not receiving HGH. Overall, men with prostate cancer had lower levels of IGF-1.

The published evidence strongly indicates that HGH does not increase the risk of cancer, does not cause treated cancers to recur, and does not cause established cancers to grow more rapidly.

THE SOURCES OF HUMAN GROWTH HORMONE

Where does human growth hormone—the kind we now inject—come from? Who makes it, who wants to sell it, who's allowed to sell it, and—the bottom line—how can you obtain a safe and reliable supply if you eventually decide that it will be a part of your personal anti-aging regimen?

These are important questions and deserve serious discussion not only for their own sakes but because they relate to the chief drawback of HGH: its high cost. Depending upon the dose that an elderly patient and his or her health care practitioner decide to administer, the cost will usually be somewhere between $4,000 and $7,000 each year—more than $75 per week. Certainly a good bit more than the price of dinner at a good restaurant on a Saturday night. And regrettably, beyond the means of most people who could greatly benefit from growth hormone replacement.

The main reason for this high price is competition—or, in this case, the lack of it. Up until now, a handful of companies have maintained a monopoly on HGH in the American market, even though there are other reputable companies overseas who make the substance and are eager to import it at a much lower price. It appears that the monopoly beginning to crack. In the next few years the price is almost certainly going to come down, and then, willy-nilly, whether our government's bureaucracies like it or not, this new era of anti-aging medicine can be more widely utilized.

Up until now, growth hormone has remained tightly restricted in the United States because various forms of exclusivity have worked in conjunction with the wishes of the FDA. Although, as a natural substance, growth hormone would appear immune to patenting, in practice, things worked out differently. Genentech, a large biotechnology corporation in the San Francisco Bay area, developed four key patents in the 1980s protecting the processes and procedures whereby HGH is manufactured. Genentech's process involves giant culture vats filled with E. coli bacteria—yes, that's the same bacteria naturally found in your body. Recombinant DNA technology allows these bacterial cultures to produce natural growth hormone.

The actual process of making the growth hormone molecule itself is no longer a terribly difficult one, now that the code sequence has been worked out for the human gene that instructs the pituitary gland to string together growth hormone's 191-amino-acid chain. The gene, once made, is transplanted into an E. coli bacteria, which is then allowed to grow and multiply in a nutrient broth at approximately body temperature. After the E. coli has grown and multiplied sufficiently, a purification process is done to separate out the growth hormone. This is currently the most difficult and sophisticated portion of the manufacturing process. Without very gentle and delicate handling, many growth hormone molecules will be damaged. Growth hormone is not simply one long chain of amino acids—it is folded and twisted in a precise manner, with its branches connected at very specific points in cross-linkages.

Hormones work by precisely fitting into receptors on the surface of cells and cell membranes in the body. The process is very similar to fitting a key into a lock. All of the little twists, turns, and grooves on a key must be exactly right or the key will not open the lock. In the same way, the exact three-dimensional configuration of growth hormone must precisely fit into cell receptors or there will be no growth hormone activity. If purification and packaging of HGH is properly done, the molecule retains its shape and will do its job.

Genentech created procedures that successfully dealt with these problems and ensured that the final product would be exactly like pure growth hormone. In the 1980s Eli Lilly, the pharmaceutical giant, tried to make the hormone using somewhat similar procedures, and Genentech sued for patent violations. After some fierce legal tussles in the federal courts in Indianapolis, the smaller but feisty biotechnology company agreed to license its process patents to Lilly in return for approximately $145 million. At that stage, both companies had approval from the Food and Drug Administration to market the hormone for pituitary deficiencies in children. And, indeed, their exclusive marketing control was not only protected by Genentech's patents but by the fact that the FDA had declared HGH an "orphan drug" and under the law granted the two companies the exclusive right for several years to be the only ones to make marketing claims regarding HGH's effectiveness against growth deficiency in children. There seems to have been an unwritten understanding with the FDA that neither company would allow their growth hormone to be used for any other purpose.

However, in 1995 orphan drug exclusivity for marketing claims ran out, and several European firms poised themselves for entry. Two of the firms, Novo Nordisk, a Scandinavian biotechnology giant, and Biotechnology General, which manufactures in Israel, make HGH by an E. coli bacterial process similar to Genentech's. Both companies maintain, however, that their processes are sufficiently different that Genentech's patents do not apply. Genentech first filed a complaint with the International Trade Commission claiming patent violation. The suit was thrown out because the presiding judge ruled Genentech was withholding important documents relevant to the case. Novo Nordisk and Biotechnology General promptly started procedures to import HGH, and Genentech just as promptly filed a new suit against them in federal court, the Southern District Court in New York City. Following that battle, Novo-Nordisk now imports rHGH into the United States, but patents still apply, royalties are being paid and the price remains high.

Happily for all of us who would like to see the price of the hormone go down, the other two European firms seem to be protected from legal challenges by Genentech.

Ares Sorono, headquartered in Switzerland, uses mammalian cells instead of E. coli bacteria as the basis of its manufacturing process and therefore is free of any patent competition with Genentech. Consequently they have entered the American market at with FDA approval. They built a new plant in the United States, where manufacture growth hormone. That bit of competition lowered the price somewhat, but it is still too expensive for most elderly Americans.

In a very interesting further development, Ares Sorono has done some very sound scientific research on the use of HGH to treat advanced AIDS patients suffering with cachexia (massive weight loss and muscle wasting). The results of that research were very positive, and they received FDA approval to market growth hormone for that indication. The muscle wasting that takes place with AIDS has a certain similarity to the muscle wasting of age, and, of course, HGH reverses both forms of wasting by similar means.

Another company, which has recently entered the market is Pharmacia AB, located in Stockholm, Sweden.

Another growth hormone manufacturer has not yet attempted to enter the U .S. market but would clearly like to. BIOFA AB is a Lithuanian company that before the collapse of the Soviet Union was an important supplier of recombinant DNA products to the former Soviet bloc. After the Soviet collapse, BIOFA privatized and received the equivalent of FDA approval in a number of other countries.

BIOFA need not fear patent disputes because they developed a form of HGH that does not infringe on existing patents. Nature’s own HGH has 191 amino acids. BIOFA has taken advantage of the fact that only the front end of the molecule, so to speak, fits into cellular receptor sites. To understand this better, picture a key fitting into a lock. The front part of the key that actually turns the tumblers must be made with absolute precision, but the handle can be square or round or oval or solid or hollow or holed. It turns out that at the nitrogen end of the amino acid sequence—what we might call the back end of the growth hormone molecule or the handle on the key— very tiny changes to the sequence have no functional significance. Consequently BIOFA produces a 190-amino-acid sequence in their form of growth hormone, which bypasses earlier patents. This may be a case of the San Francisco company being hoisted with its own petard. It has been reported that in the 1980s, hoping to circumnavigate a University of California patent, Genentech added an extra amino acid molecule at the same position to produce a 192-amino-acid sequence. This would make it somewhat difficult for them to argue the unfairness of the Lithuanian company's move. HGH with one amino acid more or less at the inactive end of the hormone structure has been proven conclusively in clinical trials to be identical in its action. The FDA approved Genentech's earlier version, which is good evidence for safety and effectiveness. Unfortunately, the FDA will still not allow BIOFA to import its product into the United States.

As demand expands, other biotechnology companies around the world are beginning to manufacture HGH. At least one company in China makes a high quality product, but like BIOFA, they remain unable to get FDA approval for importation into the USA.

As a physician, my interest is to see the cost of growth hormone go down. It is essential, however, that the high quality that currently exists be maintained. But it's probably time for us to consider the question of quality, while describing the normal procedures for obtaining growth hormone that an older person must currently follow

Beware So-called "Generic" HGH

Many individuals who want to take human growth hormone to counter the effects of aging hesitate to do so because they assume that the FDA's attempts to restrict its use to growth-deficient children means that they and their physician will be involved in some sort of illegality if they use it for other purposes. That is absolutely not the case. It is a well-established legal principle in American medicine that a physician may use any approved drug for therapeutic purposes other than those for which it was designed, if that physician feels such a use is best for his patient. This is called "off-label" use and is, in fact, quite common. In spite of the FDA's earlier and successful attempts to coerce Genentech and Lilly into restricting sales of growth hormone purely for use in the treatment of growth deficiency and dwarfism in children, the "off-label" principle still applies, and, if a supply of the growth hormone can be obtained, the doctor and his patient are perfectly within their rights in using it.

The question, of course, is how to obtain that supply.

Most of it is manufactured in Europe, although Serono now has a factory to make its product Saizen® in the United States. Because of strict FDA controls and patent protection, prices remain high despite increasing competition.

There is a great advantage achieved from these ongoing FDA controls, despite the added cost. All brand-name HGH products marketed in the USA are manufactured using very strict quality control procedures. The FDA inspects the factories and protects the end-user in that regard.

The HGH molecule is fragile and must be produced and purified with great care to insure that the end-product is perfect—identical in every respect that that produced by the human pituitary gland. If the delicate folding or cross linkages are not precise, or if two molecules hook together (polymerize), a person injecting the defective product could become allergic to the own internally produced HGH, or have some other form of severe reaction. All impurities from the manufacturing process must be removed and sterility must be maintained to prevent infection following injection. Before shipping, very lengthy and expensive testing must be performed to protect the eventual users. For that reason, the cost will probably never be as low as we’d like.

There are now manufacturing facilities overseas that take short-cuts, producing HGH that is impure, damaged or otherwise contaminated. It is made in factories that are not inspected and is being smuggled into the USA as "generic" HGH. Some is counterfeit, and packaged to appear exactly like FDA approved products, including the holographic logo on the box. I would advise against the use of any product that is not FDA approved in the USA. You should ask for the chain of possession, from an FDA approved factory right down the line into your hands, so that you can be sure that it is not a counterfeit.

If your supplier is a health care practitioner, make sure that your HGH has come through a distributor that buys directly from the manufacturer, to protect against counterfeits that enter the market through undocumented middlemen. Pharmacies that buy in small amounts have at times been victimized by counterfeiters. Above all, do not trust any of the so-called generic HGH products now being touted as cut rate prices. Ask for the name and location of the factory, and for a certificate of analysis showing that all quality control testing, as required by the FDA, has been satisfied.

You should take note of what brand of growth hormone is being provided for your use, and the vials of growth hormone should have the original labels of the manufacturer. If you have any doubt about the source of the growth hormone, ask for a certificate of analysis conducted by an FDA licensed laboratory that shows acceptable purity.

There have been reported instances of growth hormone being diluted or replaced with chorionic gonadotropin—which is difficult to distinguish in the laboratory without expensive testing. I once received reports of a growth hormone product that came in through Mexico with a German company named on the label. Mexican authorities I talked with told me that such a German company does not exist, and the product actually came from Pakistan. Whether or not it contained any growth hormone was in doubt.

Until a wider distribution of growth hormone in the United States makes it easier to acquire, finding a knowledgeable health care practitioner you can trust is your best assurance that you will not be cheated.

Stability

When you receive a supply of growth hormone, you will want to keep it refrigerated. The hormone is shipped and sold in a freeze-dried form sealed in a sterile vial, to which a weak saline solution is added when it is prepared for injection. As long as it is kept in its freeze-dried form at a comfortable room temperature not more than 90 degrees Fahrenheit, Serono’s Saizen® brand will remain stable for up to eighteen months, as printed on the label. However, once water or diluent is added, it should be used within four weeks if kept refrigerated and within two or three days if unrefrigerated. Once diluted, it should also be protected from freezing.

It's important to keep growth hormone free of contaminants, especially once it's in its liquid form. Use a new syringe every time you inject yourself—otherwise any contamination on the needle of the used syringe may get into the vial carrying contaminants. Blood residues on a used needle may also contain proteolytic enzymes that can begin to digest the remaining growth hormone in the vial and cause bacteria to multiply inside the vial.

MORE RESEARCH IS IN THE WORKS

Growth hormone is going to remain in the news because the reverberations of Daniel Rudman's original clinical trial have certainly not died down. Under the sponsorship of the National Institute on Aging, a number of new studies on the effects of growth hormone administration to the elderly are being conducted at institutions as prestigious as Johns Hopkins School of Medicine and Stanford University Medical Center. Each study is different, but some of the areas being investigated include HGH's effects on cardiovascular function, on aerobic capacity, on bone density (a treatment for osteoporosis), and on mental function.

Benefits from HGH replacement are slow and gradual, taking 6 months or more to accrue. Increases in bone density with osteoporosis take 18 months. HGH is slow and subtle in its effect, but also gentle and safe. Those with more extreme deficiencies—with IGF-1 measured at 50 or less, as occurs in the very elderly—often experience faster and more profound benefits.

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