# Testosterone Types and Delivery



## Arnold (Apr 9, 2010)

*Testosterone Types and Delivery*

*Overview*
  In FTM testosterone therapy, testosterone (often called "T" for short)     can be administered into the body in a number of ways. The most common  method    is intramuscular (IM) injection with a syringe. Other delivery methods  include transdermal    application through gel, cream, or patch applied to the skin; orally  by swallowing    tablets (this method is uncommon as it has been shown to have negative  effects    on the liver); sublingually/buccally by dissolving a tablet under the  tongue    or against the gums; or by a pellet inserted under the skin. The  T-delivery    method used will depend on the type of medication available in the  country of    treatment, the health risks/benefits for the patient, personal  preference, and cost. Testosterone is not stored by the body for future use, so in order to  maintain    healthy levels, it must be administered in timed intervals and in  appropriate    dosages. Injectable and subcutaneous T pellets remain active in the  body the    longest. Injectable T is typically administered between once a week to  once    every three weeks, and subcutaneous T pellets are replaced every 3-4  months.    Transdermal T (patch, gel, or cream) is typically applied to the skin  in smaller    daily doses; oral and sublingual/buccal T are also typically taken  daily. 

*"Normal" testosterone Levels
*An individual's testosterone levels are usually confirmed through a  blood    test called a "serum total testosterone test." Testosterone exists    in your bloodstream in two forms-- "bound" testosterone and "free"    testosterone. The majority of bound testosterone in the body is  chemically bound    to a protein called "sex hormone binding globulin" (SHBG). The  remaining    bound testosterone in the system is mostly bound to albumin, another  protein.    Free testosterone is not chemically attached to any proteins and is  considered the "active" form of testosterone, as it is readily available     to bind to androgen receptor sites on cells.

 A serum total testosterone test measures the total of bound and free T  in the system. What is considered a normal test level of combined bound  and free testosterone    in male bodies can range anywhere from 300-1100 ng/dl (nanograms per  deciliter).    Levels will vary with age and individual factors.
 It is useful to also separately measure the level of free  testosterone in the system,    as this may be more indicative of how hormone therapy is progressing.  Levels    of free testosterone can range between 0.3%-5% of the total  testosterone count,    with about 2% considered an optimal level. Ask your doctor to check  for both    total and free levels of testosterone in your system.

  Remember that because everyone's bodies have differing sensitivities  to androgens,    T levels themselves will not necessarily indicate results in terms of  masculinization.    The levels are merely a guideline by which you and your doctor can  begin to    measure progress. Your results and your dosing should be guided by  your overall    health (especially the health of your heart and liver), your progress  in masculinization,    and how your body and moods react to different dosages. Testosterone  therapy    is not a one-size-fits-all approach-- be sure to monitor your health  and feelings    closely, and remember that even a small adjustment in dosage (either  increase or decrease)    can make a big difference.

*A note of caution about greatly increasing  your T    dosage*
  During the first months of T therapy, many trans men feel impatient  waiting for changes    to happen. Some may consider doubling or tripling their dose, thinking  that    the more they put in, the faster the changes will come. However, as  was mentioned    in the "FTM  Testosterone Therapy Basics"    section, dramatically increasing your dose might have the effect of _slowing_     your changes. This is because excess testosterone in your body can be  converted    into estrogen by an enzyme called "aromatase." This conversion is    part of the body's natural feedback system-- if there is an abundance  of testosterone    in the body, it is converted ("aromatized") to estrogen in order to    maintain a "normal" hormonal balance. Therefore, taking very large    doses of testosterone might not be a great idea. Be patient; if you  are not    seeing results in a reasonable period of time, and/or your T levels  are low,    discuss modifying your dosage with your doctor.
 To learn more about the side-effects and health issues around  testosterone    therapy, please see the "FTM Testosterone    Therapy and General Health" section.
http://www.ftmguide.org/ttypes.html#top
*Testosterone esters: what they are and how  they work*
  Much of the testosterone that is prescribed for the purposes of  hormone therapy    is in the form of testosterone "esters." An ester is simply a name for  a chemical    compound that is formed from reaction between a carboxylic acid and an  alcohol.    A simple chemical diagram of this reaction is shown below in Figure A.  Figure    B shows the chemical structure of free testosterone (chemical formula C19H28O2)  as well as two different    esters of testosterone (testosterone cypionate and testosterone  enanthate).









 There are a number of different esters of testosterone, including the  commonly    prescribed injectables of testosterone enanthate and testosterone  cypionate,    as well others such as acetate, propionate, phenylpropionate,  isocaproate,    caproate, decanoate, and undecanoate. Each of these different esters  is a molecular chain    composed of carbon, hydrogen, and oxygen atoms. The main difference  between the different esters   is how many carbon and hydrogen atoms make up the chain. For example,  the propionate    ester is composed of 3 carbons, 6 hydrogens, and 2 oxygens, whereas  the cypionate    ester is composed of 8 carbons, 14 hydrogens, and 2 oxygens.

 Esterification of testosterone is done in order to improve the  solubility of    testosterone in oil, which in turn slows the release of the  testosterone from    the site where it enters the body.

 Testosterone, in its free, non-esterified form, has poor solubility  in either    oil or water-- though it can be suspended in water. Non-esterified  
testosterone    is available in an aqueous injectable form with the drug name  "Aquaviron."    However, this form of testosterone stays active in the body for a very     short period of time (only a matter of hours).    Because of this, it must be injected on a daily basis in order to  maintain a    continuous level of testosterone in the blood. Therefore it is rarely  used for    testosterone replacement therapy as an injectable.

 Once you have added an ester group to testosterone, it becomes even  less soluble    in water and more soluble in oil. Additionally, as a general rule, the  more    carbon atoms there are in an ester, the more soluble the ester is in  oil. For    example, testosterone propionate (with 3 carbon atoms in the ester  group) is    less soluble in oil than testosterone cypionate (with 8 carbon atoms  in the    ester group). Remember, this is general, simplified rule; the  solubility of a molecule depends on structural factors that are beyond  the scope of this section.

 So generally, the more carbons the ester group has, the more soluble  in oil it becomes,    and the less soluble in water. The term for this ratio between oil and  water    solubility is called the "partition coefficient"-- the higher the    solubility in oil, the higher the partition coefficient.

 The partition coefficient of the ester in question is important  because is    effects how long the drug itself stays in the system. If the  testosterone transfers    too quickly from the oil to the blood, the result is a sudden spike in  testosterone    which then rapidly drops once the dose has been used up. In the  example of free testosterone injected into    the muscle from a water suspension (as in Aquiviron, mentioned above),  the testosterone    is essentially immediately available to the bloodstream due to its low  partition    coefficient, and thus there is an immediate spike of testosterone  which is used    up quickly in the body.

 Testosterone cypionate, on the other hand, has a high partition  coefficient.    When injected into the muscle, the drug remains in its esterified form  in a    deposit in the muscle tissue. From there, it will slowly enter the  circulation    as it is picked up in small quantities by the blood. Once the  esterified testosterone    is brought into the blood stream, "esterase enzymes" cleave off the    ester chain in a process known as "hydrolization," thus leaving the    testosterone in its free form to perform its various actions and  effects.
 When people speak of whether a particular testosterone    ester is "fast acting" or "slow acting," they are usually referring to  the partition coefficient/solubility in oil. As    described above, esters with more carbon atoms will generally be more  soluble in oil-- they are often referred to as "slow-acting"    esters (they stay active in the system longer). Esters that are less  soluble in oil are often referred to as "fast-acting"    forms of testosterone, referring to the fact that they are more  quickly available    and used up in the blood stream.

 For trans men who are using injectable testosterone, slow-acting  esters tend to be preferred, as fewer injections are needed over time to     keep the blood levels of T reasonably constant. Testosterone enanthate  (7 carbons)    and testosterone cypionate (8 carbons) both take about 8-10 days to be  fully released in the system,    and so they are typically injected once every 7-14 days. Testosterone  propionate    (3 carbons) takes about 3-4 days to be fully released in the system,  and must be injected in smaller doses at least    weekly if not twice weekly. For this reason it is not often prescribed  for men    in transition.

http://www.ftmguide.org/ttypes.html#top*
Testosterone delivery methods *

*Injectable testosterone 
*The dosage amount and timing for injectable testosterone will  depend largely    upon which ester is being used, as well as the individual's own  response to    the hormone. In general, dosages will vary between 50 mg and 300 mg  per injection,    depending on the ester and the dosing regimen. An average injectable  dose is    about 200-250 mg every two weeks, though many trans men inject 100 mg  every week or every 10 days,    or other variations depending on their own bodies' needs and  sensitivities.    Again, the exact dosage required will vary from person to person, and  health    and well-being should be carefully monitored while determining an  individual's    ideal dose.

 Some doctors recommend decreasing the dosage of injectables to  100-150 mg every    two weeks for those trans men whose ovaries are inactive, or who have  had their ovaries    removed. Again, this will vary from person to person.

 There are a number of different types of injectable testosterone;  those available    may differ depending on the country in which you reside. The drug  names for    the same ester of testosterone may also differ depending on the  company who    produces it. This is not an exhaustive list, though it does cover the  main injectable    forms of T which are used by trans men for testosterone therapy.

 Finally, testosterone esters are typically suspended in either  cottonseed oil    or sesame seed oil. Some people find that they may have an allergic or  skin reaction    to one of the oils. Certain brand-name testosterone esters    are mass produced using one oil or the other (as noted below), but by  using    a compounding pharmacy, you can have any testosterone ester suspended  in your    choice of oil (with a proper prescription). (For    more information about compounding pharmacies, click here.)


*Injectable esters commonly used by trans men for testosterone  therapy:**Testosterone enanthate: *Chemical  formula C26H40O3
    Testosterone enanthate is one of the main forms of testosterone  prescribed      to trans men in the United States. It is a slow-acting ester with a  release time      between 8-10 days. The name-brand of T-enanthate available in the  United      States is called "Delatestryl," which is suspended in sesame oil.      Testosterone enanthate is typically injected anywhere between once  every week      to once every three weeks. Generic testosterone enanthate can also  be obtained      through a compounding pharmacy; such pharmacies can mix T-enanthate  in sesame, cotton seed, or any other appropriate oil. (For more information      about compounding pharmacies, click here.)

*Testosterone cypionate: *Chemical  formula C27H40O3
    Testosterone cypionate is the other main injectable form of  testosterone prescribed      to trans men in the United States. It is a slow-acting ester with a  release time      between 8-10 days, similar to that of enanthate. The name-brand of  T-cypionate      available in the United States is called "Depo-Testosterone," which      is suspended in cottonseed oil. Testosterone cypionate is typically  injected      anywhere between once every week to once every three weeks. Generic  testosterone      cypionate can also be obtained through a compounding pharmacy; such  pharmacies      can mix T-cypionate in sesame, cotton seed, or any other appropriate  oil.(For      more information about compounding pharmacies, click here.)

*Sustanon 
* "Sustanon" is the brand name for two formulas of injectable  testosterone that contain  a blend of      esters. "Sustanon 100" contains three testosterone esters:  testosterone propionate (C22H32O3),  testosterone phenylpropionate (C28H36O3),  and      testosterone isocaproate (C25H3803).       "Sustanon 250" contains four testosterone esters: testosterone  propionate (C22H32O3), testosterone  phenylpropionate (C28H36O3),  testosterone isocaproate (C25H3803),  and testosterone decanoate (C29H4603).  Both formulas feature fast-acting and slow-acting esters, and can be  injected anywhere      from once every week to once every four weeks. Sustanon is  prescribed outside of      the United States.​*Other injectable esters of testosterone:**Testosterone propionate:* Chemical  formula      C22H32O3
    Testosterone propionate is a fast-acting ester with a release time  of 3-4      days. To keep blood levels from fluctuating greatly, propionate is  usually      injected between one to three times a week. It is for this reason  that it      is not usually prescribed for FTM hormone therapy. Some users also  report      that propionate is a more painful injection, with swelling and  noticeable      pain around the injection site. Brand names of testosterone  propionate include      "Testovis" and "Virormone."

*Testosterone phenylpropionate:*  Chemical      formula C28H36O3
    Testosterone phenylpropionate is a slow-acting ester, with a release  time      of 1-3 weeks. A popular name brand for T-phenylpropionate is  "Testolent."      Testosterone phenylpropionate is also one of the components of  Sustanon and      Omnadren.

*Omnadren*
    "Omnadren" is the brand name for a blend of four testosterone  esters:      testosterone propionate (C22H32O3),  testosterone phenylpropionate (C28H36O3),       testosterone isocaproate (C25H3803),  and testosterone decanoate (C29H4603).       In the past, Omnadren consisted of a blend of different esters, but  now is      essentially the same formula as Sustanon, mentioned above. It  features both      fast-acting and slow-acting esters, and can be injected anywhere  from once      every week to once every four weeks. It is sometimes prescribed in  parts of      Europe.

*Aqueous testosterone suspension
* In the United States, injectable aqueous (non-esterified)  testosterone      is available, but it is very short-acting (it is completely released  in the      system within a matter of hours). Therefore, it is not typically  used for      men in transition, as it would require constant re-injection to  maintain      regular blood levels. The brand name for aqueous testosterone  suspension is      "Aquaviron."​http://www.ftmguide.org/ttypes.html#top
*Transdermal testosterone*
  The term "transdermal" refers to topical delivery through    the skin, by the use of a patch, gel, or cream.

 Transdermal testosterone is usually applied to the skin daily in  small doses    in an effort to keep a steady level of testosterone in the system at  all times.    This approach avoids the "peaks and valleys" in T-levels sometimes    associated with injectable testosterone. With injectables, T levels  can reach    a low-point a few days before the next shot is due, which can cause  irritability,    hot flashes, and low energy in some users. Daily transdermal  application can    help alleviate such problems. Indeed, some trans men who regularly use  injectable    testosterone sometimes supplement with a gel or patch during the last  few days    of their dosing cycle to maintain their T levels.

 Transdermal application is also attractive to those individuals who  are not    comfortable with needles and injections.

 However, there are some disadvantages to transdermal delivery. Some  forms of    daily transdermal testosterone application, particularly the patch,  are substantially    more expensive than injectable testosterone. 
Testosterone patches  often cause    skin irritation and/or allergic reactions to users. They can fall off  with excessive    sweating, and they must be fully protected with plastic when swimming.  Testosterone    cream and gel can be transferred by direct skin contact with a  partner; special    care must be taken with female partners who wish to avoid potential  virilization.

*Testosterone patches
*There are currently two brand-name testosterone patches available  in the    United States: "Androderm" and "Testoderm." (Note that there    are two forms of Testoderm available: a scrotal patch and a  non-scrotal patch.    The non-scrotal patch, "Testoderm TTS," is described herein). Generic    testosterone patches are not yet available. Both Androderm and  Testoderm TTS    are very fast-acting once they have permeated the skin. The  testosterone in    the patches is suspended in an alcohol-based gel.
 In order to deliver testosterone efficiently into the body, chemical  enhancers    are added to the patch to increase permeability of the skin. It is  these enhancers    that are often the cause of skin irritation in many users. Some  individuals    find Testoderm TTS to be less irritating to the skin than Androderm,  but this    will vary from person to person.*Androderm
* Androderm patches come in two doses: 2.5 mg/patch and 5.0  mg/patch. The      actual amount of testosterone in the 2.5 mg patch is 12.2 mg, and  the actual      amount in the 5.0 mg patch is 24.3 mg. The reason is that much of  the testosterone      in the patch will not manage to get into the system. So, for  example, the      aim of the 2.5 mg patch is to get about 2.5 mg successfully into the  bloodstream      per day. Therefore, it is possible to absorb slightly more or  slightly less      than the 2.5 mg of the patch's ideal dosage (the same reasoning, of  course,      applies to the 5.0 mg patch as well).
   Androderm patches are usually applied on the back, abdomen, thighs,  or upper      arms. Because the active area of the patch is covered, the wearer  does not      have to worry about skin contact with a partner. Dosages will vary  between      2.5 mg - 10 mg daily, by applying a single patch or combination of  patches.      As with any form of testosterone, dosage should be determined by  your overall      health, your testosterone levels as checked by your doctor, and your  progress      in masculinization.

*Testoderm TTS
* There are two types of Testoderm patches: one is intended for  scrotal      application, and one for application on other areas of the body.  Testoderm      TTS refers to the non-scrotal version of the patch-- this is the  patch that      should be used by trans men.
    Testoderm TTS patches come in two doses: 4.0 mg/patch and 6.0  mg/patch.      As with Androderm, the actual amount of testosterone in these  patches is greater      than the listed dose. The reason is the same as explained above in  the Androderm      section. 

   Testoderm TTS patches are usually applied on the back, abdomen,  thighs, or      upper arms. Because the active area of the patch is covered, the  wearer does      not have to worry about skin contact with a partner. Dosages will  vary between      4.0 mg - 10 mg daily, by applying a single patch or combination of  patches.      As with any form of testosterone, dosage should be determined by  your overall      health, your testosterone levels as checked by your doctor, and your  progress      in masculinization.​*Testosterone gel and cream*
  There are currently two brand-name versions of testosterone gel  available in    the United States: Androgel and Testim. There are no brand-name  testosterone    creams at this time. Both cream and gel formulations of testosterone  can be    made by compounding pharmacies. (For more information    about compounding pharmacies, click here.) Gel formulations of  testosterone    are typically alcohol-based, whereas creams are typically safflower  oil-based.    The testosterone in creams and gels is typically very fast-acting once  absorbed    through the skin. Thus, it must be applied once or twice daily to  maintain  T levels.
 Creams and gels are applied directly onto the skin. Care must be  taken to avoid    skin-to-skin contact with a partner on the site of application.  Transfer of    the testosterone from the site can be prevented by keeping the area  covered.*Androgel
* Androgel is a clear, alcohol-based gel that contains 1%  non-esterified      testosterone. It is very fast-acting once it has been absorbed by  the skin,      and so must be applied 1-2 times daily to maintain T levels. It is  available      in either unit-dose packets or multiple-dose pumps. The unit dose  packets      contain either 25 mg or 50 mg of testosterone. Approximately 10% of  the applied      testosterone from the packets is absorbed into the system, resulting  in an      effective dose of 2.5 mg or 5.0 mg, respectively.
   Androgel should be applied to clean, dry skin and should not be  applied to      the genital area. Application sites should be allowed to dry for a  few minutes      prior to dressing. Hands should be washed thoroughly with soap and  water after      application. 
   In order to prevent transfer to another person, clothing should be  worn to      cover the application sites. If direct skin-to-skin contact with  another person      is anticipated, the application sites should be washed thoroughly  with soap      and water. Users should wait at least 2 hours after applying before  showering      or swimming; for optimal absorption, it may be best to wait 5-6  hours.

*Testim
* Testim, like Androgel, is a clear, alcohol-based gel that  contains 1%      non-esterified testosterone. It is very fast-acting once it has been  absorbed      by the skin, and so must be applied 1-2 times daily to maintain T  levels.      It is available in 5.0g unit-dose tubes. A 5.0g unit dose tube  contains 50      mg of testosterone. Approximately 10% of the applied testosterone  from the      tube is absorbed into the system, resulting in an effective dose of  5.0 mg.    

   Testim should be applied to clean, dry skin-- preferably to the  shoulders      and/or upper arms. It should not be applied to the genitals or to  the abdomen.      Application sites should be allowed to dry for a few minutes prior  to dressing.      Hands should be washed thoroughly with soap and water after  application. 
   In order to prevent transfer to another person, clothing should be  worn to      cover the application sites. If direct skin-to-skin contact with  another person      is anticipated, the application sites should be washed thoroughly  with soap      and water. Users should wait at least 2 hours after applying before  showering      or swimming; for optimal absorption, it may be best to wait 5-6  hours.

*Compounded creams and gels
* Compounded creams and gels can be mixed by compounding  pharmacies, and      are similar in dosing, application, and precautions to what is  described above      for Androgel and Testim.

   There are two advantages of using compounding pharmacies for  testosterone      gel or cream. The first is cost: until a generic version of the gel  is available,      compounded gel will usually be the cheaper alternative. The second  is customization:      your doctor can write a prescription of varying concentration for  gels or      creams. (For more  information about compounding      pharmacies, click here.)​http://www.ftmguide.org/ttypes.html#top
*Oral testosterone 
*Chemically unbound testosterone, if taken orally, is not effective  for masculinization    since it is immediately deactivated by the liver. However, two  chemically-modified    forms of testosterone have been successfully shown to induce masculine  secondary    sex characteristics when taken orally: methyltestosterone and  testosterone undecanoate.  *Methyltestosterone (C-17 alpha methylated testosterone)*
    Methyltestosterone is one of the earliest available oral  testosterones. Its      chemical structure is the hormone testosterone with an added methyl  group      at the c-17 alpha position of the molecule. The use of oral c-17  alpha methylated      testosterone for masculinization is obsolete due to its toxicity to  the liver.      As such, *methyltestosterone is not recommended for FTM hormone  therapy*.      Brand names include "Metesto," "Methitest," "Testred,"      "Oreton Methyl," and "Android."

*Testosterone undecanoate*
    Testosterone undecanoate is not a c-17 alpha alkylated hormone.  Therefore,      it is considered a safer oral form of testosterone. It is designed  to be absorbed      through the small intestine into the lymphatic system, posing less  burden      on the liver. Brand names for testosterone undecanoate include  "Andriol,"      "Androxon," "Understor," "Restandol," and "Restinsol."      It is not available in the United States.
   One disadvantage of orally administered undecanoate is that it is  eliminated      from the body very quickly, usually in 3-4 hours. Thus, frequent  administration      is necessary-- usually between 3-6 capsules a day. This can prove to  be expensive when compared to injectable testosterone.
   Finally, when used in FTM hormone therapy, it has been reported  that oral testosterone undecanoate has not      always been successful in suppression of menstruation.​http://www.ftmguide.org/ttypes.html#top
*Sublingual/buccal testosterone 
*Sublingual and buccal testosterone delivery works by either  placing a dissolving    tablet under your tongue (sublingual) or by placing a tablet against  the surface    of the gums (buccal). It is different from oral delivery in that very  little    of the substance is swallowed, avoiding potential liver toxicity.*Sublingual
* Sublingual testosterone can be obtained through compounding  pharmacies.      (For more  information about compounding pharmacies,      click here.) 

*Buccal
* In 2003, the FDA approved a sustained-release buccal  testosterone tablet      called "Striant." It acts by adhering to the buccal mucosa (the      small depression in the mouth where the gum meets the upper lip  above the      incisor teeth). Once applied, the tablet softens and delivers  testosterone      through the buccal mucosa, where it is then absorbed directly into  the bloodstream,      bypassing the gastrointestinal system and liver.
    The recommended dosage for Striant is to replace the tablet about  every      12 hours, though a different dosing schedule or number of tablets  might be      required depending on the needs of the patient.​http://www.ftmguide.org/ttypes.html#top
*Subcutaneous testosterone pellet 
* Another relatively new form of testosterone delivery is via a  pellet of    pure, crystalline testosterone implanted beneath the skin. The pellets  are about    the size of a grain of rice, and are typically placed in the buttocks  or abdomen.    The insertion of the pellets is a quick procedure, usually done under  local    anesthesia. Pellets are typically replaced after 3-4 months.  "Testopel"    is a brand name for testosterone pellets in the United States.
 A 200 mg testosterone pellet releases testosterone at a steady rate  of 1-3    mg per day. Several pellets can be inserted at the same time to  increase dosage.

 Some users have reported problems with the pellets working their way  out from    under the skin.

http://www.ftmguide.org/ttypes.html


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## weldingman (Apr 9, 2010)

Very nice study Robert. Very user friendly.


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## klc9100 (Apr 9, 2010)

good shit, man.  thanks.


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## Dark Geared God (Apr 9, 2010)

yep


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## heavyiron (Apr 9, 2010)

The trans men part is a little weird. Anything you want to tell us Robert?


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## weldingman (Apr 9, 2010)

lol


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## lucifuge (May 28, 2010)

Great info Prince! Thanks for taking the time.


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## MDR (May 28, 2010)

Nice read-thanks for posting this info.


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