Pharmaceutical Name:  Testosterone

Chemical Structure: 17β-hydroxy-4-androsten-3-one

Delivery Method: Normally Injectable

Typical Vial/Tablet doses: Normal range 50mg/ml to 400mg/ml


You will no doubt be aware that testosterone is the primary male hormone which is produced predominantly in the testes, and to a much lesser degree, is also secreted from the adrenal cortex. The profound effects of testosterone in the human body are plain to see in boys who are progressing through the pubescent years with marked changes occurring including facial and body hair growth, deepening of the voice, muscular increases, increased sexual desire and competitive behaviour and the prevalence of oily skin and acne, amongst others. Testosterone is also indirectly responsible (through its conversion to oestrogen (estrogen)) for bone maturation and the subsequent closure of the epiphyseal plates which is ultimately responsible for bone length and thus overall height.

First isolated from bull testes in 1935, the next hurdle was to identify methods of administration of a synthetic variant. Nowadays, there are a host of options available, including transdermal, oral and injectable versions.

Transdermal testosterone administration is most commonly seen in legitimate Testosterone Replacement Therapy (TRT). Relatively small dosages are provided by a patch that is worn on the skin. This method is widely accepted for the intended medical use though offers little for the steroid using bodybuilder.

Orally, a user essentially has two choices. The first option is Methyltestosterone, which, as the name suggests, is simply a testosterone molecule with an added methyl group, which greatly increases its bioavailability by assisting the drug to survive the first pass in hepatic (liver) metabolism. However, there appears to be two problems with this drug: Being methylated, it will be liver toxic which in essence will limit the user both in terms of dosage and cycle length; and also the lack of esterification which not only necessitates frequent ingestion, but also causes sharp peaks in concentration levels, especially given the relatively high dosages necessary for meaningful muscular growth. This in turn encourages a host of typical side effects, most notably perhaps, an increased risk of gynecomastia since the aromatisation of methyltestosterone produces a particularly troublesome methylated estradiol.

There is, however, an alternative oral testosterone, namely Andriol / Restandol which are manufactured by Organon. This product has a novel administration method in that an oil based testosterone with an attached undecanoate ester is absorbed through the lymphatic system, thereby avoiding hepatic metabolism, the need for methylation and its inherent risks. Each crimson coloured capsule contains 40mg of the steroid plus its undecanoate ester, which means only around 25mg is actually testosterone. Designed for use with TRT patients, it appeared that a safe oral testosterone solution was found. However, there are issues that remain problematic: It has been shown that wide variances in steroid uptake are possible between different individuals using the drug, as well as variances in steroid uptake with the same user from each dose. This makes it difficult to determine with any level of certainty how much of the hormone is actually being delivered. For the bodybuilder, there are other concerns too, in that some claim that Andriol is much less likely to pose problematic side effects when compared to other injectable forms. This misconception is probably due to the fact that the actual amount of steroid delivered is low from such a suggested cycle. Relatively high daily dosages (upwards of 320mg) are required to provide comparable results to a modest injectable cycle, with incidences of side effects then appearing similar too. Furthermore, the high cost of maintaining a meaningful Andriol cycle makes this a poor choice from the options available. For the purposes of this article therefore, we shall concentrate solely on the injectable versions, and the choices that lay therein.

There are four main esterified, injectable testosterone preparations, differing only by the carbon ester chain attached to the steroid molecule. Simplified, the length of ester chain will determine the half life (time taken to metabolise half of the drug administered) of the parent hormone; the shorter the ester, the shorter the half life and therefore requiring frequent administration. The opposite is true for longer esters. Testosterone is universally considered the ‘King’ of all the steroids, and whilst most cycles will consist of testosterone by itself, or contain a testosterone as a base when stacking other steroids, it is not compulsory to do so.

Suggested Cycles/Uses

Testosterone Propionate (Test Prop) is the shortest ester variant which requires administration every day, or every second day. This can create issues for longer cycles, where the user may tire from frequent injections and naturally, this compound is not suited to the needle-shy. Furthermore, testosterones with a propionate ester are typically less concentrated than longer esterified variants. This means that there are lower amounts of hormone (measured in milligrams, mg) suspended in a given amount of oil carrier (measured in millilitres, ml). Typically, pharmaceutical grade versions will have a concentration of 50mg/ml, with underground labs tending to manufacture at 100mg/ml. Whilst this increase in concentration is desirable in terms of reducing the total volume of carrier oil that is injected, the result can be injection discomfort, experienced both at the time of administration and in some cases, for several days thereafter. This problem appears to stem from the fact that propionate is less soluble than longer esters, and is prone to ‘crashing’ out of the oil carrier and crystallizing, especially where a higher concentration of steroid is present.

Testosterone in any form is capable of contributing to large increases in mass and strength. Propionate is no different in this regard and users will find results coming rapidly due to the fast acting nature of the ester.

Many users have reported that test prop results in lower incidences of side effects (water retention, gynecomastia, etc) than other esters. This has prompted widespread use in ‘cutting’ cycles where the user wishes to avoid unnecessary bloating from typical ‘mass’ steroids. The user is able to continue their cardio efforts without hindrance and is able to maintain a relatively lean appearance which is important in gauging fat loss progress. Whilst these viewpoints are numerous and difficult to ignore, the phenomenon perhaps stems from more obvious factors; cutting cycles tend to be much smaller than mass cycles. The reason lies in that the user is not concerned with adding further muscle; their primary objective is to strip fat whilst maintaining existing muscle mass. Generally, the amount of anabolics required to help with this objective are much smaller than those needed for a priority of mass gain, which has obvious implications in terms of the severity of side effects.

(Novice cutting cycle)
Testosterone Propionate 100mg eod, weeks 1-8
Winstrol (oral) 50mg ed, weeks 4-8.5

(Intermediate mass cycle)
Testosterone Propionate 75mg ed (150mg eod), weeks 1-10
Nandrolone PhenylPropionate 75mg ed (150mg eod), weeks 1-10
Anadrol 100mg ed, weeks 1-5

(Intermediate/Advanced cutting cycle)
Testosterone Propionate 100mg ed, weeks 3-12
Trenbolone Acetate 50mg ed, weeks 3-12
HGH 5IU ed, weeks 1-12
T3 Taper, weeks 5-12 (see 8 & 6 week T3 Dosages)
Clenbuterol / Ephedrine, weeks 1-12

Testosterone Enanthate and Cypionate are almost identical with the only difference being an additional carbon in the ester chain for Cypionate. Distinguishing between them is almost impossible and are therefore considered identical in terms of both effect and results. In reality, all other variables being equal, enanthate is a slightly better value product due simply to the reduced ester weight. This accounts for 28mg of every 100mg of testosterone enanthate, in contrast to 30mg per 100mg for cypionate. Although we’re splitting hairs here, the difference only amounting to 20mg per week in a 1gram per week cycle, it is nevertheless worth noting.

These longer estered testosterones require infrequent injection and are therefore perfectly suited to longer, typically mass cycles, where levels of steroids used tend to be higher. In contrast to Propionate, these testosterones are manufactured with a much higher mg/ml ratio without any pain issues for the user. 200-250mg/ml are typical, and makes higher dosed cycles a much easier prospect in terms of reduced oil volume. Indeed, some underground manufacturers have taken this to the extreme, with some versions boasting concentrations of 400mg/ml though this practice is considered unnecessary and such a preparation is likely to cause substantial injection soreness.

When using either enanthate of cypionate, a weekly dosing regime is perfectly adequate, though splitting twice is usually preferred as steroid concentration levels drop significantly around day four, and by doing so will ensure better stabilisation. As you would expect from any variation of testosterone, mass and strength gains are very impressive, helping solidify testosterone’s dominance in the typical steroid user’s arsenal of available drugs. Examples of commonly seen cycles including these esters:

(Novice mass cycle)
Testosterone Enanthate/Cypionate 1000mg week 1
Testosterone Enanthate/Cypionate 500mg pw, weeks 2-10

(Advanced mass cycle)
Testosterone Enanthate/Cypionate 750mg-1250mg pw, weeks 1-12
Deca 600mg-800mg pw, weeks 1-10
Dianabol 40mg-50mg ed, weeks 1-4
Testosterone Propionate 100mg-150mg ed, weeks 12-15
Trenbolone Acetate 100mg-150mg ed, weeks 10-15

The final injectable testosterone option is actually a blend of esters, all contained in the same preparation. The most common of these testosterone blends include Sustanon and Omnadren, manufactured by Organon and Jelfa respectively. For example, Sustanon 250 contains the following in each 1ml ampoule:

30mg Testosterone Propionate
60mg Testosterone Phenylpropionate
60mg Testosterone Isocaproate
100mg Testosterone Decanoate

This type of steroid is often medically given to patients who opt for injectable testosterone therapy to treat their hypogonadism. It is favoured within the medical community for this purpose due to the fact that the blend of esters facilitates a much more uniform release and metabolism of the testosterone which in turn negates the need for frequent injections. This feature is apparent from the fact that some patients receive their injections as infrequently as fortnightly. Clearly, this form of testosterone is highly valued in the bodybuilding community, particularly by users who wish to limit injections and inject on a weekly basis.

It is thought by some that by avoiding a frequent administration schedule (such as every second day), a user will in some way ‘waste’ the benefit of the short prop and phenylprop esters. How they arrive at this conclusion is anyone’s guess! The short esters are metabolised and utilised by the body regardless of the frequency of administration and to suggest that they somehow disappear into thin air is ludicrous. The nature of the ester blend is designed in such as way that the average rate of ester release is relatively uniform, not too dissimilar in essence to that of a single ester of enanthate or cypionate. In view of this, the use of Sustanon/Omnadren is interchangeable with enanthate/cypionate when constructing cycles.

Novice users will often ask which of the long esterified testosterones is the best. The short answer is that they are as good as each other, the only real differences occurring due to poor manufacturing processes by certain labs which may affect the actual amount of steroid contained resulting in an under/overdosed product. Other factors that may give a user the perception that one type is better might have been a better diet or training routine which may have led to a better result than previously experienced from another type of ester.

Possible Side Effects

It will be of no surprise that steroids that can potentially lead to substantial results tend to have a greater risk of associated side effects, and in this regard testosterone is no different. Being both a considerable anabolic and androgenic hormone, the user should take necessary precautions when using testosterone to limit potential problems that may arise. Due to its profound effects on the hypothalamic pituitary testicular axis (HPTA) and subsequent suppression of endogenous testosterone production, the need for an adequate post cycle therapy (PCT) is paramount; see the MuscleTalk article: Clomid, Nolvadex and HCG in Post Cycle Recovery.

Testosterone interacts readily with the enzyme aromatase, which results in estrogen conversion. High circulatory levels of estrogen can lead to a number of issues including gynecomastia (the formation of male breast tissue, often referred to in slang terms as ‘gyno’ or ‘bitch tits’), water retention and fat deposition. It is clear that some users are much more sensitive to the effects of increased estrogen levels than others, and may notice typical early signs of the condition even from using a very modest dose of testosterone such as 500mg weekly. The user should recognise these early warning signs which can be just one or a culmination of: swollen, puffy, painful, lumpy, itchy or tender nipples. Should any of these symptoms become apparent, it would be prudent to control both existing circulating estrogen and the level of future estrogen conversion. This is achieved through the use of a Selective Estrogen Receptor Modulator (SERM) such as Tamoxifen (brand name Nolvadex) which, being a weak estrogen in itself will compete and occupy the breast tissue estrogen receptor rendering much of the troublesome circulating estrogen inert, and by the use of an anti-estrogen drug such as Proviron or Arimidex. These assist by binding and therefore blocking the effects of the enzyme responsible for estrogenic conversion, thereby reducing actual circulating estrogen levels. For more information see the article Combating Oestrogens and Progesterone.

As mentioned above, water retention (oedema) is commonplace when using testosterone, often resulting in bloatedness and a loss of definition. This may be undesirable in certain cycle situations so extra consideration should be given to both the dosage and whether other ancillary drugs may be necessary. Excessive oedema may give rise to a considerable increase in blood pressure and steps should be taken to control the elevation. Drinking plenty of fluids and reducing salt intake are straightforward examples which will help in this respect. Other methods occasionally employed would be the use of diuretics and/or anti-hypertensives such as Catapres (clonidine hydrochloride), though such measures are not without risk and should not be taken without due diligence.

Testosterone is also capable of reduction by the enzyme 5-α reductase (5-ar). This is responsible for the conversion into a dihydro metabolite. In the case of testosterone, 5-ar conversion results in dihydrotestosterone, more commonly known as DHT. It achieves this by removing the C4/C5 double bond on the A ring and by adding two atoms of hydrogen. DHT has a several fold increase in potency over testosterone, having a much greater affinity for the androgen receptor. Whilst this may appear beneficial, there are other considerations.


Unfortunately, removal of the C4/C5 double bond results in strong interaction with another enzyme, 3α hydroxysteroid dehydrogenase (3α-HSD). Found in abundance in muscle tissues, 3α-HSD reduces DHT to anabolically useless metabolites. At the same time, DHT (through conversion from testosterone) interacts very strongly with the androgen receptor in tissues where the 5-ar enzyme is found abundantly, namely in scalp, skin and prostate tissues. This has obvious implications for those who have a pre-disposition for male pattern baldness (MPB) or who are at risk of or have been diagnosed with benign prostate hypertrophy (BPH). Some users who are prone to the acceleration of their MPB condition opt to use the drug Finasteride (Proscar) which is an effective type II 5-ar inhibitor, thereby reducing DHT conversion in the scalp and prostate. It’s worth noting however, that although using finasteride largely negates DHT derived problems, it will not influence the androgenicity of testosterone itself, so hair loss in those prone, is still a very real risk.

Testosterone and its androgenically stronger metabolite DHT are also responsible for increases in the secretion of oils by the sebaceous glands of the skin. This often leads to unsightly acne, particularly prevalent on the chest, face, shoulders and upper back. Perhaps the most outwardly visual sign of a person using anabolic steroids, acne can range from mild, to truly disturbing, and a situation that may lead to permanent scarring. It may take several weeks particularly from longer esterified testosterones, for signs of acne to become apparent or troublesome due to delays in the build up of androgens, but conversely, the problem is likely to persist long after the cessation of a testosterone cycle.

Sustanon flu’ or ‘sus flu’ is a fairly common occurrence when using testosterone. The problem has been given this name by some users who experience flu-like symptoms upon commencing a testosterone cycle. It’s worth noting that this problem is primarily associated with short esterified testosterones such as Propionate (including Sustanon which include a Prop/Phenylprop ester), though is possible in reality from any testosterone ester. Although there are varying opinions which suggest a cause for this issue, the properties and effects of testosterone metabolite Etiocholanone make it appear particularly plausible. Etiocholanone is a pyrogen and elevations in circulatory levels are associated with feverish effects. Propionate as we know is a fast acting ester resulting in a rapid elevation in testosterone and thus etiocholanone levels. It’s certainly possible that this rapid increase results in some users experiencing flu-like symptoms during the early stages of a cycle.