how does it work and what are the side effects?

Men, on the other hand, are likely to be offered either three-monthly injections of a long-acting formulation of testosterone called Nebido. Sustanon – a combination of four forms of testosterone – is also commonly prescribed and requires an injection every two to four weeks. In both cases, the injections will be done by a doctor or nurse. Gels such as Tostran and Testogel are available too, and these are rubbed in at home daily, with the aim of creating more stable blood levels of testosterone. 

Injections, however, can offer better and faster absorption into the bloodstream, so Stevens prefers a different protocol. His clinic prescribes daily injections, which patients can give themselves at home. This allows for much smaller “microdoses” to be administered regularly, “mimicking the body’s physiology as closely as possible” and creating stable levels. This protocol is, he suggests, attracting growing recognition. In 2022, the Society for Endocrinology added more frequent injections to their treatment guidelines. 

Where do you put testosterone cream on your body?

Women usually rub testosterone cream or gel onto their thigh, says Newson, making sure the skin is clean and dry. Things are a little more variable for men. Tostran is rubbed into the abdomen or both inner thighs, while Testogel is often applied to the shoulders. Different studies show different absorption rates when the medication is applied to various parts of the body, which means the products have different application instructions. 

And when it comes to injections, “The vast majority of my patients inject into the subcutaneous tissue, which is essentially the space between the skin and the muscle, in the belly or love handles,” says Stevens. “It’s painless – much like being a diabetic.” Plus, subcutaneous jabs have a slower rate of absorption. 

What should I do if I forget a dose?

If you are on a daily treatment regime, don’t panic, says Stevens. “One of the beauties of microdosing is that you won’t end up feeling close to how you felt before you began your protocol, unless you miss multiple injections.” 

Newson agrees. “It doesn’t really matter what time of day you apply it,” she says. “So if you forget, just take it as soon as you remember.” 

Testosterone cream side effects

“When it’s prescribed properly, side effects are vanishingly rare,” says Newson. Mild acne is occasionally reported. “Some women find hair grows at the spot where they rub it in, as testosterone stimulates the hair follicles. Others, rarely, say they feel a bit agitated and wired right at the start, as their bodies adjust to the presence of a hormone that has been missing in these quantities for a while. If that’s the case, we can reduce the dose, then very gradually increase it,” she says. 

“In a well-balanced protocol, there should be no side effects since all we are doing is normalising your physiology,” agrees Stevens. Cardiovascular complications have traditionally been the biggest worry due to associations between testosterone replacement treatment (TRT) and haematocrit which, he explains, “is essentially a rise in red blood cell count, thickening the blood and putting a strain on your cardiovascular system”. This may be associated with an increased risk of heart attack, stroke and blood clots. But, says Stevens, “There’s likely to be an underlying reason – either a bad protocol or sleep apnoea, dehydration or kidney disease.” In fact, in 2023, a major study of more than 5,000 men, published in The New England Journal of Medicine, found that the risk of “major adverse cardiac events” was not raised by the use of TRT.

Fertility is another common concern since, Stevens explains, your natural production of testosterone may be reduced as a result of ongoing testosterone replacement, leading to a reduction in sperm. Alongside testosterone, his clinic administers hCG or human chorionic gonadotropin – a female pregnancy hormone that (counterintuitively) helps preserve testicular size, function and fertility when given to men undergoing TRT.