Your prescribing doctor will rarely tell you how testosterone replacement therapy works. Here’s what you need to know.
There are many misconceptions about how long the effects take Testosterone replacement therapy (TRT) comes into play. Granted, most men realize that it takes longer than weeks or months for new muscle to appear and old fat to shed, but these men often have completely unrealistic expectations about how quickly their sexual performance needs to improve .
Many expected that their minds would immediately begin to be consumed by fantasies of women with stunning bodies, and that their previously moribund masculinity would rise like Nosferatu from the underpants grave to hunt their bounty of the flesh.
I think the latter misconception and other false ideas about TRT stem from sci-fi movies or series where someone swallows a pill or injects a green liquid into their neck and instantly transforms into something scary and scary, but TRT isn’t like that.
While its effects are many and notable, generally speaking each of its effects has its own timeline. Some, like unexpected bursts of energy, come quickly, but others, like libido, are more fickle and arrive in due time.
While there haven’t been any studies specifically dedicated to charting the timeline of TRT’s effects, as an aside or footnote, there’s plenty of research showing roughly how long it takes for testosterone to work its magic.
However, developing an accurate timetable is tricky. For one thing, people who are truly hypogonadal notice changes more quickly. This is in stark contrast to those who just want to boost their testosterone levels a little bit so they can be more manly, fit, and loving. In other words, the less hypogonadal you are before starting TRT, the smaller the increase in circulating T will be and the longer the duration of treatment will be required before changes are detected.
With this in mind, here is a general synopsis of some of the research reported by Saad et al. in the European Journal of Endocrinology.
Most effects on TRT and muscle mass/strength were dose-related. If you just sprayed testosterone instead of taking a testosterone bath, there wouldn’t be much noticeable change.
For example, if you look at the study subjects, you can see that muscle mass varies from 0.4 kg to 16.4 kg (the latter over the course of a year). Likewise, leg lift strength increases ranged from 11.6 kg to 76.5 kg.
Several studies have used doses between 50 mg. Testosterone gel 150 mg per day. On a daily basis, these individuals almost universally showed significant increases in leg press strength, bench press strength, and stair climbing strength (?) over 6 months.
Another, use 200 mg. On biweekly testosterone enanthate, strength and mass were found to continue to increase during the first 12 months of TRT, but largely disappeared thereafter.
Despite the ambiguity of the observations, some trends and commonalities were noted, mainly that the effects of TRT on muscle strength and size were readily observed after 12-20 weeks, while the maximum effect was reached after 6 or 12 months. (TRT-induced gains may continue after that, but only at a snail’s pace unless the dose is increased).
Libido, erections, and all things sexual are complicated beasts. Low libido can be related to testosterone levels, but can be exacerbated by medical/psychological conditions like diabetes or depression. I don’t mean to be overly diplomatic here, but if your partner thinks that sex is just another chore, or that they look like a sack of potatoes when they don fishnet underwear, that can also suffer.
all this will be doubled erectionin addition to all the factors listed in the previous paragraph, these factors are greatly influenced by poor arterial endothelial function and health, neuronal integrity, psychological factors, and of course testosterone concentrations.
I would say that TRT is not a panacea when it comes to libido and erections. That said, the research reveals some generalities. Most of the time, sexual desire and sexual thoughts/fantasies come to the fore very quickly. The idea of a sexy sugar plum fairy in a thong starts to show within 21 to 30 days, but some studies only notice these effects after about 3 months.
Also, these TRT sugar plum fairies wand wand their underperforming penises after about 3 weeks, usually in the morning woods.
However, maximum results are usually seen within 3 to 6 months, although in some cases it may take up to a year. Notably, one study showed that giving testosterone undecanoate (TU) to patients with “veno-occlusive dysfunction” (poor ducts) resulted in recovery in a minimum of 3 months and a maximum of 11.5 months Full erectile function.
Testosterone, bless its heart, is a major player in obesity, blood sugar control, and lipid metabolism. Typically, after TRT there is an increase in muscle mass with a decrease in body fat, often resulting in a constant weight loss (especially in those not doing resistance training).
Fat, at least in men, preferentially accumulates in the midsection, and this is where TRT works best for fat loss. Studies have shown that waist circumference decreases in about 3 months and lasts over 24 months.
While this weight loss effect is often attributed to an increase in metabolism or energy expenditure, it is more likely caused by biochemical influences. In particular, testosterone “regulates the lineage determination of mesenchymal pluripotent cells by promoting the differentiation of mesenchymal pluripotent cells to the myogenic lineage and inhibiting their differentiation into the adipogenic lineage through an androgen receptor-mediated pathway.” “
Sorry to throw such an obscure sentence at you, but I was struck by its biochemical “poetry” and had to throw it in. Regardless, this means that testosterone can tell certain cells to become muscle cells instead of fat cells, which explains how TRT can have such a dramatic effect on body composition.
To this day, many physicians still believe that TRT has adverse effects on blood lipids, but the opposite is true. Total cholesterol drops in as little as 4 weeks, but in most cases it takes up to 3 months for this number to start dropping dramatically.
In terms of TRT’s effects on the two major cholesterol components, low-density lipoprotein (LDL) typically decreased over an impressive 24 months, while high-density lipoprotein (HDL) increased over the same period of time.
Likewise, triglyceride levels begin to optimize in as little as 4 weeks, but may continue to optimize for up to 24 months.
Similar to cholesterol and triglycerides, doctors often assume that TRT raises blood pressure (BP), but the opposite is true. A drop in diastolic blood pressure (the “bottom” number on a blood pressure reading) was observed over a period of 3 to 9 months, reaching a nadir after about 12 months. Although less common, systolic blood pressure sometimes responds (decreases) in the same way to TRT.
Likewise, a decrease in resting heart rate was observed after 40 to 44 weeks. Even more impressive, a reduction in arterial stiffness (less arterial stiffness means less stress on the heart and stiffer erections) was observed in as little as 48 hours.
However, blood pressure concerns may not be true for those who gain a lot of muscle through TRT, as simply getting bigger increases blood pressure.
Many people still think that testosterone is what causes you to kill your parents and drive your four wheeler over woodland critters laughing maniacally.But paradoxically, it is often men low testosterone Moody, depressed and even angry, men with normal or high testosterone levels are usually sociable and gregarious.
A UCLA researcher found that men with low T scores were indeed likely to be meaner and more aggressive than men with high T scores, but that once the mean men were given the T substitution, their attitude and anger disappeared up.
Men with low T are also more prone to depression, but usually their depression, as acerbic as they can be, goes away with TRT. Some studies have found that testosterone can bring depression into remission in as little as 3 to 6 weeks, but it likely takes 18 to 30 weeks to exert its personality-altering effects.
TRT also seems to play a role in what I call “proper aggressiveness”. I mean, sometimes it’s appropriate to yell and let the dogs of war slip away. I’m not talking about being a one-touch DB who snubs anyone who dares bump into him, but asserting yourself when you need to. This could include fighting against an asshole boss who asks you to work overtime on the weekends without getting paid, telling your neighbor who is practicing taiko at 2am to stop working, or something as simple as giving your least favorite politician the middle finger.
This change in personality, and the ability to make decisions faster or think better critically, can take up to a year to kick in (if not in the first place).
Here’s an overview in bullet point form of what you can expect during the TRT (including some effects I didn’t discuss):
- Occasional bursts of energy, kind of like a human puppy run.
- Improved insulin sensitivity (detectable only with blood tests).
- May dispel the fog of depression.
- Lower levels of stress hormones (again, this can only be detected with a blood test).
- The erection fairy comes (leaves a coin and birth control pill under the pillow).
- Cholesterol may start to drop (blood test).
- May eliminate depression completely.
- You got more party invites, Mr. Funny Guy, you.
- The waist circumference is visibly narrowed.
- Blood pressure may have dropped.
- Increased production of red blood cells.
- Bone density increased significantly.
- The biggest sexual benefits may already be kicking in.
- Emotionally, you may be a different person.
- Mental acuity is at its peak. Decisions are made faster and appropriate aggression is evident.
- More muscle mass, less body fat.
- sleep more deeply.
- Improve blood sugar control.
- Increase athletic ability.
- Learn more in general.
One thing I didn’t mention is the TRT mode, which is gel/cream or injection. The schedule should be about the same both ways, but gels/creams can be a bit tricky as the absorption rate can vary depending on how much you use them, the thickness of your dermis, or whether you have bathed and scrubbed in the last month.
I also need to reiterate that most of the observations on TRT schedules are for men who are truly hypogonadal, not just men who are thrill seeking. “In other words, signs and symptoms of testosterone deficiency occur at different circulating testosterone thresholds (Saad).”
For example, if you don’t really have a problem with low testosterone, TRT may not have as much of an impact on conditions like depression as if you were a person with normal values who just wanted a little help gaining muscle and losing fat .
The timing or strength of the effect is also highly dose dependent. Most of the observations reported here were made in men who received adequate doses. As with any drug or supplement, the “Goldilocks” approach seems prudent: not too little, not too much, but the right amount (which should be determined by symptoms rather than some doctor’s opinion on how much to give).
One thing should be clear, though: in most cases, TRT has something to offer a lot of people, especially those who really need it.
Not ready for a shot yet? try this:
- Saad F et al. Onset of testosterone therapy and time span for maximal effect. European Endo Magazine. (2011) 165 675-685.
- Wang C et al. Testosterone replacement therapy improves mood in hypogonadal men–a clinical research center study. Journal of Clinical Endocrinology and Metabolism. 1996 Oct;81(10):3578-83. PubMed.