For an overview of the full treatment approach and benefits, please refer to our Testosterone Replacement Therapy treatment page.
Historical Context of Testosterone and TRT
Historically testosterone was associated with bodybuilders abusing vast quantities of anabolic substances often injected through large bore needles into muscle. Abuse of these drugs and without proper monitoring can result in life changing complications. It is no surprise therefore that the stigma associated with injecting testosterone into muscles remains, albeit to a lesser degree as we are starting to shift the connotations towards the health and wellbeing benefits of TRT.
Methods of Administering TRT
There are different ways of administering TRT from infrequent intramuscular injections to frequent injections using fine needles to oral preparations.
Intramuscular and Subcutaneous Injections
The goal for most people is to find a treatment plan that provides them with stability in how they feel. Whilst an injection into muscle, like nebido, every 8 to 12 weeks is certainly more convenient it has it’s drawbacks, primarily in that it does generate somewhat of a peak and a trough between injections. The ultimate route to stability of levels is regular injections of fast but long acting testosterone esters like cypionate or implantable pellets that slowly release testosterone, though there are also some practical difficulties with this method. Testosterone cypionate is suspended in low enough viscosity diluents to be injected and drawn up using fine needles and because of the lower viscosity it tends to be well tolerated when injected into the fat beneath the skin (not dissimilar to the way insulin is taken by patients with diabetes). This is often favoured by patients as they can use fine needles and inject in the abdomen quickly, safely and in a fairly pain free way. Whenever you inject there will be a degree of scarring and this applies to both muscle and fat. Scar tissue tends to be broken down and absorbed by the body, though this will happen at different rates from one person to another, as will the severity of scar that forms vary. What’s important is that when injecting into the fat, to give the body ample opportunity to clear the micro scar, rotating your injection site prevents repetitive trauma to the same piece of tissue. If the same tissue is repeatedly injected into scarring of the fat cells can become so marked that you can feel an area of hardness in your abdomen called lipohypertrophy. Subsequent injecting into such an area would result in very little of the medication being absorbed by the body as it tends to remain in this walled off ball of hardened fat.
As injecting is the most effective means of taking TRT, avoiding forming scar tissue is a key consideration. It’s not uncommon for patients who solely inject subcutaneously to develop some areas of scarring that they can feel; it can feel like areas of hard or lumpy tissue. My advice is to rotate as much as possible, not just between different sites for subcutaneous injecting but also between subcutaneous and intramuscular injecting. Injecting using fine needles into the muscle, whether the thigh or the glutes, is an entirely different proposition to the relatively barbaric large bore needle used by those abusing steroids.
For further guidance on alternative approaches and optimising your injection technique, you might find our Which TRT is Right for Me? page useful.
Shelf Life and Sterility of Multi-Use Vials
Testosterone cypionate is most often in a multi-use vial that tends to last around 3 months. Questions have been raised about the sterility of a vial from which medication is drawn up repeatedly over a 3 month period. Whilst some guidelines state a 28 day use of multi-use vials, this is a fairly arbitrary shelf life as there are multiple studies that have found multi-use vials to be safe for at least 6 months when being drawn from twice daily.
For insights into the Safety Profile of TRT, please refer to our dedicated page.
Alternative Formulations of TRT
Topical Preparations
Other formulations include creams, which are absorbed to a greater degree than gels. They can either be applied directly to the skin or via a patch. These are largish molecules that need to navigate the fairly robust barrier, the skin. The skin’s permeability also changes significantly depending on temperature, skin hydration, age, skin damage etc. Aside from absorption being an unpredictable variable, transference of the drug from the patient to family and friends through direct or indirect contact is another problem. I particularly advise patients with children in the household of this risk as it’s not uncommon for testosterone cream or gel to be found on bathroom surfaces or even transferred from shared towels.
Oral Formulations
The next area of interest is without a doubt testosterone in tablet form. Testosterone undecanoate has been developed as an oral version of TRT over many years, initially with liver issues when the drug would be metabolised. This has now been overcome and there are numerous branded agents available and whilst they’ve been used in the US for a few years, they are still fairly new to the UK market. The little research that’s been done shows good results with the oral forms, albeit they can take around a week to reach a stable level in the blood. Risk profiles of the oral forms are similar to that of injectables and creams. The main challenges with the oral formulations has been how well they can be absorbed by the gut and the individual variability in the extent to which they get broken down by the liver when they pass through.
For more on alternative approaches, our Alternatives to TRT page provides additional context.
Pellet Implants
Finally, pellets might be the most fuss-free option on a day to day basis, where a small pellet that slowly releases testosterone constantly is implanted just under the skin. It’s much more difficult with these to tweak protocols and if there are any concerns, whereas with the other forms you can simply pause treatment, it’s more of an undertaking to have to remove a pellet and then re-insert it.
For more detailed discussions on treatment options, including considerations when coming off TRT, please visit our Coming Off Testosterone Replacement Therapy (TRT) page.
Additional Resources
For further information and to expand your understanding of TRT and its benefits:
Learn more about the Benefits of Testosterone Replacement Therapy.
For a comprehensive overview of what TRT is, visit our What is TRT? page.
- To learn more about our TRT services, please have a look our TRT treatment clinic page.
