What are the Typical Drugs used to Treat Low Testosterone and how do they Work?

There are three primary classes of drugs used to treat low testosterone and in each class several different options. The primary drug used to treat low testosterone is of course testosterone, and there are many different forms and options. However, while testosterone is primary, there are other medications that are often needed and essential to sound and proper therapy. It’s not always enough to simply increase testosterone levels; what’s more important is creating a balance between varying hormone levels, especially testosterone and estrogen. With this in mind, let’s take a look at the varying drugs used to treat low testosterone, how they work and when they are needed.


Testosterone, actual testosterone is the primary drug used to treat low testosterone, specifically exogenous testosterone. Exogenous testosterone refers to testosterone provided outside of the body rather than testosterone made by the body or endogenous. Regardless of where it came from, it is the same hormone and the body makes no distinguishing difference. The body simply sees all testosterone as testosterone, and it is one of the most essential hormones to the human body. When levels fall or become too low, the only thing that will remedy the situation is testosterone either by way of natural production or through exogenous administration. If your body no longer has the ability to produce enough on its own, exogenous administration is the only thing that will work. A good way to look at it is like gas in your car. There are things we can do to improve gas millage and we’re always looking for the best price we can get, but when the tank is low the only thing that will fill the tank back up is gasoline. The same can be said of low testosterone. There are things we can do to help prevent our testosterone levels from falling, at least to a degree, but once testosterone levels are low the only thing that will fill the tank is testosterone.

When choosing a testosterone to meet your needs, the first decision to make revolves around the form of administration. There are four specific forms of administration, and they all have positive attributes but they are far from equal when it comes to effectiveness. The four forms of testosterone administration include:

  • Transdermal
  • Oral
  • Pellets
  • Injectable 

Transdermal Testosterone – This is any type of testosterone that is applied to the skin and absorbed through the skin into the body. Transdermal testosterones include creams, gels and patches. The most well-known transdermal testosterone is AndroGel, which is simply a gel/cream that you rub on your inner-thighs, abdomen or upper-arms and shoulders. AndroGel itself is simply a brand name; there are numerous forms of testosterone gel/cream that are identical. This type of testosterone is easy to use, but it will not be affective for approximately 20% of all men. Some men simply cannot absorb transdermal testosterone creams. Of those who can absorb it, many will find it works very well, but as time goes by their body begins to adapt and they no longer receive the full benefit. Many men who respond very well often find that after a few months they have very little response left. Where you will fall is impossible to predict, but it is something to keep in mind.

Another popular transdermal testosterone is AndroDerm. AndroDerm is a patch that contains a reservoir of testosterone cream/gel that slowly releases into the body over the course of the day. Not as popular as it once was, testosterone patches can actually be more effective an efficient than testosterone gels or creams. AndroDerm will carry a bioavailability two times greater than AndroGel and is designed to mimic natural testosterone release. Unfortunately, as with transdermal creams and gels some men will not respond to the patch, but a positive note is that a patch limits the possibility of transferring the testosterone by touch to another individual.

Oral Testosterone – This is any type of testosterone taken by mouth and while many are somewhat effective, most are extremely toxic to the liver and rarely recommended. Most forms of oral testosterone are C17-alpha alkylated (C17-aa), which refers to a structural change to the hormone at the 17th carbon position. This structural change allows it to survive the first pass through the liver, but it also makes it extremely hepatotoxic. The exception to this rule would be Andriol Testocaps, which are an oral testosterone gel cap that has been esterified. This form of oral testosterone is in no way toxic to the liver; unfortunately, the drug only carries an approximate 7% bioavailability. It can take a large dose to reap the benefits and the cost of Andriol Testocaps is relatively expensive. Further, the compound has never been approved to treat low testosterone in the U.S. despite an extremely high safety rating.

Testosterone Pellets – This is a pellet comprised of nothing but testosterone and binders that are inserted through a small surgical procedure directly under the skin. The rate of absorption is very high and even, meaning it is very easy to maintain stable testosterone levels during therapy without unwanted highs or lows. Testosterone pellets, Testopel being the most well known, also carry the advantage of infrequent administration. Pellets can be inserted and the individual doesn’t have to think about his testosterone therapy until he needs pellets inserted again, which can be once every 3-5 months depending on need. Of course, the downside is the small surgical procedure. Some men have also reported discomfort at the area of insertion as they can feel the pellets the entire time they are inside the body.

Injectable Testosterone – This refers to any type of testosterone that is administered by injection. This is without question the number one way to treat low testosterone, and more importantly the best way. Although highs and lows in testosterone levels are possible, they are extremely easy to avoid with a proper injection protocol. How often the hormone needs to be injected is dependent on the type of testosterone being used. In the U.S. Testosterone Cypionate is the most commonly prescribed testosterone for the treatment of low testosterone. The second most common would be Testosterone Enanthate. Both forms are virtually identical in that the individual should not notice any difference in the effectiveness of one form over another.

Injectable testosterones are defined by the ester that is attached; in the case of the two aforementioned testosterones the esters are Cypionate and Enanthate. The ester attached to the testosterone hormone controls the release time of the hormone. Once the ester is detached from the hormone, the hormone becomes active in the body. Regardless of the ester that is attached, once the ester is removed you have the same identical testosterone hormone. The ester attached to the hormone does not affect the hormone.

Once Testosterone Cypionate or Testosterone Enanthate is injected, testosterone levels will peak 48-72 hours after injection. At approximately the one week mark post injection, testosterone levels will fall back close to baseline. For this reason, injectable Testosterone Cypionate or Testosterone Enanthate should be administered at minimum once per week in order to maintain stable levels. There will be a large dip in levels towards the end of the week, but another injection is shortly around the corner. In order to prevent any significant dip in levels, the best course of action is to split your weekly dose into two equal injections. For example, if you are prescribed to take 100mg per week, you could inject 50mg on Monday and another 50mg on Thursday.

Beyond Testosterone Cypionate and Testosterone Enanthate, other forms of injectable testosterone used include Testosterone Suspension, Testosterone Propionate and Testosterone Undecanoate. Testosterone Suspension is pure testosterone in that it has no ester attached and must be injected frequently. This form of testosterone is generally only prescribed in emergency cases. Testosterone Propionate, the original commercially available testosterone like Testosterone Suspension is rarely prescribed anymore. Some physicians will prescribe it short term in emergency cases as it is a rapid acting testosterone, but it is rarely needed. Then we have Testosterone Undecanoate, best known by the trade name Nebido. This is a very slow acting testosterone with a very large ester that only has to be injected once every 3-4 months. Highly effective and very appealing based on the infrequent injection schedule; unfortunately, it has yet to be approved for use in the U.S. despite enjoying approval and enormous success across most of the globe.

The final types of injectable testosterone include testosterone blends such as Sustanon 250. Testosterone blends like Sustanon are comprised of four testosterones, in this case Testosterone Propionate, Testosterone Pheynlpropionate, Testosterone Isocaproate and Testosterone Decanoate. A mixture of small and large esters, the idea is to provide fast acting benefits with long lasting results eliminating the need for frequent injections. Unfortunately, due to the small esters, in order to avoid peaks and valleys in levels, compounds like Sustanon 250 need to be injected at minimum 1-2 times per week. Further, as with Nebido, testosterone blends like Sustanon 250 and Omnadren are not U.S. approved, but are rather commonplace in many parts of the world, especially Sustanon 250.

Aromatase Inhibitors:

Aromatase Inhibitors (AI’s) are an often overlooked part of testosterone therapy. Not all men need an AI but approximately 70-75% of all men will. The use of an AI is often needed in an effort to control estrogen. Testosterone itself is the primary male hormone, but estrogen is important as it plays numerous roles in our body. However, if estrogen levels go too high, this can cause many problematic symptoms such as water retention and gynecomastia (male breast enlargement). It can also lead to the promotion of high blood pressure if water retention gets out of hand.

How it works – Our estrogen comes from testosterone. Testosterone converts to estrogen via the aromatase enzyme through the process of aromatization. Men who have high levels of body fat will typically aromatize testosterone at a higher rate. However, even at a low body fat some men metabolize testosterone with a lot of aromatase activity. Genetics will be the final determining factor of the rate of aromatization. Equally important is the amount of testosterone you’re taking; more testosterone means there is more to aromatize. For the low testosterone patient, he should never need a large amount of testosterone, but sensitivity will still play a role.

When we use an AI, by design it inhibits the aromatase process; it inhibits the conversion of testosterone to estrogen. Equally important, AI’s will lower estrogen levels. It is very possible to lower estrogen too much, and when levels fall below the optimal range symptoms that are often associated with low testosterone can abound; in fact, they can be even worse. For this reason, AI’s should only be used when needed, and it is extremely important that no more is used than necessary. Finding the proper balance of estrogen and testosterone is extremely important in any testosterone therapy plan. Where one individual needs to be can vary dramatically from one man to the next, but there are optimal ranges. Estradiol (estrogen) will be optimal at 20-30ng/dl while total testosterone will be optimal at 700-1100ng/dl and free testosterone optimal at 20-30ng/dl.

Human Chorionic Gonadotropin:

Human Chorionic Gonadotropin or hCG is a powerful polypeptide hormone that is found in pregnant women during the early months of conception. It is this specific hormone that is responsible for indicating a positive result on a pregnancy test. For the low testosterone patient, this hormone is beneficial as it mimics another naturally produced hormone in Luteinizing Hormone (LH). LH, along with Follicle Stimulating Hormone (FSH) is one of the hormones responsible for natural testosterone production with a strong emphasis on LH. By administering hCG, this provides the body more LH and stimulates the leydig cells in the testicles resulting in natural testosterone production. As a result, testosterone levels increase, which is the primary objective of a low testosterone patient.

By administering hCG along with exogenous testosterone, this will keep natural testosterone production going. With the use of exogenous testosterone, the brain tells the testicles to stop making testosterone as the body is receiving all it needs from outside sources. This idea bothers some men, but keep in mind, the low level individual isn’t producing enough testosterone on his own to begin with. However, with the inclusion of hCG, natural production stays online and will provide an approximate 20% boost in testosterone levels. More importantly, for the individual wishing to have children on therapy, hCG will ensure he remains potent; in fact, it will increase spermatogenesis and he will more than likely increase the odds of conception.

hCG is also extremely useful to the low testosterone patient in that it will help maintain stable testosterone levels. Many men find their levels go up and down in between injections of testosterone. This can occur even with a sound injection protocol. However, the use of hCG in between testosterone injections will provide a nice boost in testosterone and help to keep levels stable.

An important note – there are two types of low testosterone, primary hypogonadism and secondary hypogonadism. Primary means the testicles no longer have the ability to produce enough testosterone. Secondary means the testicles work fine but the signal from the pituitary, specifically LH isn’t strong enough. hCG will do very little for the man suffering from primary hypogonadism, but it will work very well for the secondary individual.

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Testosterone dose-response relationships in healthy young men.

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  • http://www.steroid.com/Testosterone-Cypionate.php
  • http://www.steroid.com/Testosterone-Enanthate.php
  • http://www.steroid.com/HCG.php

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