Testosterone without a prescription and online sellers: the real risks, and why no website selling it in Spain is legal

You search for "buy testosterone online" and dozens of websites appear, with bundles, spotless photos of vials and even a supposed medical consultation included. It is worth saying this bluntly and only once: in Spain, testosterone is a prescription-only medicine, and the distance selling of prescription medicines is prohibited. Only medicines that do NOT require a prescription may be sold over the internet, and only by authorised bricks-and-mortar pharmacies listed in the AEMPS DISTAFARMA register, identified by the clickable EU common logo. Any website selling testosterone with delivery to Spain is therefore operating outside the law. That said, the interesting part is not the warning: it is understanding what you are really risking, which risks are documented and which are repeated myths, and what route does exist if you suspect your testosterone is low.

Why no website selling you testosterone is legal

The framework is easy to check. Distance selling of medicines to the public in Spain is limited to those not subject to medical prescription, and the seller must be an authorised bricks-and-mortar pharmacy appearing in DISTAFARMA, the AEMPS public listing. That European logo you see on legal websites is clickable and takes you to the official register: if it leads nowhere, it means nothing. Testosterone is prescription-only, so by definition it does not fit into that scheme.

The usual grey-market trick is to slot in a form or a video call and call it an "online medical consultation". That does not make the transaction legal: what the law prohibits is the distance selling of the prescription medicine, not merely the absence of a prescription. Nor is it fixed by self-generated quality seals, PDF certificates of analysis or reviews hosted on the site itself.

The practical difference lies in traceability. Since February 2019, under Directive 2011/62/EU on falsified medicines and Delegated Regulation (EU) 2016/161, legal packs in the EU carry an anti-tampering device and a unique identifier in a 2D barcode. That makes it possible to know which batch each box came from, to withdraw it if a problem emerges and to report adverse effects to the pharmacovigilance system. A vial bought from a website has none of this: if something goes wrong, there is no batch to trace, no manufacturer to hold to account and no recall possible.

The risk from the product is not the same as the risk from the molecule

It is worth separating two things that often get mixed up. One is what testosterone does in the body, which has been studied in clinical trials using controlled product. The other is what is inside a vial of unknown origin, which is anyone's guess. The risks described for grey-market products include uncertain content (a dose different from the one on the label, a different molecule or simply no active ingredient at all), lack of sterility in clandestine vials with abscesses, cellulitis or sepsis, contaminants, transmission of HIV infection, hepatitis B and hepatitis C through sharing equipment, and the complete absence of prior screening.

That screening is not red tape. Before any androgen treatment is considered, the assessment covers haematocrit, PSA, blood pressure, lipid profile, a history of prostate cancer or breast cancer, sleep apnoea and any wish to have children. Buying online skips precisely the step that prevents serious problems, and adds one of its own: nobody reviews the blood tests afterwards.

On falsification, in 2017 the WHO estimated that roughly 1 in 10 medical products in low- and middle-income countries is substandard or falsified. It is a figure that gives a sense of the scale of the phenomenon, but it cannot be extrapolated to Spain or to the European online market, and there is no reliable figure for how many anabolic steroids seized in Spain are mislabelled. We would rather say so than invent a percentage.

What testosterone actually does: neither miracle nor poison

The myth that costs the most is the one about expectations. In the TTrials (around 790 men aged 65 or over with testosterone below 275 ng/dL, NEJM 2016), testosterone achieved a modest but significant improvement in sexual function and did not reach a significant benefit for vitality; for walking distance, the trial designed to measure it showed no difference, and an improvement only appeared when the participants of all three trials were pooled. In other words: in the most favourable scenario, with controlled product and follow-up, it is not the energy switch that the marketing promises.

At the other extreme, it is not true that it does nothing either. Bhasin and colleagues showed in 1996 (NEJM) that supraphysiological doses - 600 mg of enantate weekly - increase lean mass and strength even without training. Anabolic steroids do work; the debate is about the biological and legal price paid for it, which is exactly what these websites do not tell you.

On cardiovascular safety, TRAVERSE (NEJM 2023) studied testosterone gel versus placebo in around 5,246 men aged 45 to 80 with symptomatic hypogonadism and cardiovascular risk: it demonstrated non-inferiority for major adverse cardiovascular events, but an excess of atrial fibrillation, pulmonary embolism and acute kidney injury was seen in the testosterone group. Read that carefully: the trial does not say testosterone is safe for the heart, and it certainly says nothing about supraphysiological doses or about product of unknown origin. In 2014 the EMA, through the PRAC, reviewed the cardiovascular risk and concluded that the evidence was not conclusive, recommending its use only in confirmed hypogonadism. The US Food and Drug Administration changed the labelling in 2015: it is not approved for a decline in testosterone due solely to ageing, and a warning about possible cardiovascular risk was added. If you want the detail on how it is given and what to realistically expect, we cover it in the guide to testosterone therapy (TRT).

The effect almost nobody mentions when selling: fertility

This is where physiology leaves no room for negotiation. Any exogenous androgen, even at replacement doses, suppresses GnRH and with it LH and FSH through negative feedback. As LH falls, intratesticular testosterone collapses; under normal conditions it is 50-100 times the concentration in blood and it is what sustains spermatogenesis. The expected result is oligozoospermia or azoospermia and testicular atrophy.

It is not true that low doses are exempt, nor that "post-cycle therapy" guarantees full recovery. If you want to have children, exogenous testosterone is contraindicated, and the alternatives - hCG, FSH or clomifene, the latter used off-label in Spain - are managed by andrology or endocrinology, not by a shopping basket. We explain that approach in the article on enclomiphene and clomiphene for raising testosterone without compromising fertility.

Myths worth dismantling with data

"Injections wreck your liver." Technically false. Serious hepatotoxicity - peliosis hepatis, cholestasis, hepatic adenomas - is associated above all with oral 17-alpha-alkylated steroids such as stanozolol, metandienone or oxymetholone, and not typically with injected testosterone esters. Exaggerating the wrong risk makes people ignore the real ones.

"Testosterone causes prostate cancer." The evidence does not support a causal relationship, although it is contraindicated where prostate cancer is known to be present. And "it triggers fits of rage" is not a good description of what is known either: the psychiatric effects documented with anabolic steroid use include irritability and aggression, hypomania and a dependence syndrome with depression on withdrawing the drug, a risk that is usually under-reported.

The class risk that is most underestimated is a different one: erythrocytosis or polycythaemia, dose-dependent and carrying a thrombotic risk. The classic threshold for stopping treatment is a haematocrit above 54%, and to know that you need periodic blood tests. If you buy online, nobody asks for them.

As for SARMs, often presented as the "clean" alternative: they are approved neither by the US Food and Drug Administration nor by the EMA, there is a 2017 FDA alert, and there are published cases of hepatotoxicity. And on the opposite side of the counter, the so-called natural boosters such as tribulus or D-aspartic acid do not raise testosterone; we go through the studies in our review of supplements for raising testosterone.

The underlying problem: many people who buy it do not have hypogonadism

Late-onset hypogonadism is less common than the noise online suggests. In the European Male Ageing Study (Wu FC et al., NEJM 2010), prevalence in European men aged 40 to 79 was around 2.1%, defined by three sexual symptoms plus total testosterone below 11 nmol/L and free testosterone below 220 pmol/L, rising from around 0.1% between the ages of 40 and 49 to close to 5% between 70 and 79. By contrast, lifetime use of anabolic steroids has been estimated at around 3.3% of the general population in a meta-analysis (Sagoe D et al., Annals of Epidemiology, 2014), with 6.4% in men and 1.6% in women.

Correct diagnosis requires two total testosterone measurements, fasting, early in the morning and on different days. Never on symptoms alone or on a standalone questionnaire. If low testosterone is confirmed, the next step is to request LH, FSH, prolactin and SHBG, because management changes according to the type: primary (low testosterone with high LH and FSH), secondary or central (low or inappropriately normal LH and FSH), functional (due to obesity, metabolic syndrome, sleep apnoea, alcohol or chronic illness, and potentially reversible) and anabolic steroid-induced. We have set out the symptom side in the article on low testosterone and hypogonadism.

Before starting hormones, the Endocrine Society (2018) and EAU guidelines insist on treating reversible causes: weight loss, because adipose tissue aromatises testosterone into oestradiol; obstructive sleep apnoea; alcohol; insufficient sleep; control of diabetes and metabolic syndrome; and a review of drugs such as opioids, corticosteroids, some antipsychotics and antidepressants, or finasteride. Along those lines, in the T4DM trial (Lancet Diabetes & Endocrinology, 2021) testosterone undecanoate added to a lifestyle programme reduced the incidence of type 2 diabetes at two years compared with placebo, but all participants received the lifestyle intervention and the drug is not approved for preventing diabetes.

One nuance that comes up often: many men who buy testosterone are in fact trying to solve an erection problem. PDE5 inhibitors, sildenafil and tadalafil, are the first-line treatment for erectile dysfunction, are prescription-only medicines and do not require testosterone. We compare the differences between them in sildenafil vs tadalafil.

What Spanish law says beyond the website

Unlike the United States, where testosterone has been a Schedule III controlled substance since the Anabolic Steroid Control Act of 1990, in Spain it does not appear on the list of narcotic drugs and is dispensed on an ordinary medical prescription. That makes the legal route, in practice, fairly accessible: your GP and, where appropriate, referral to endocrinology or an andrology unit.

There is a criminal dimension in the sporting context: article 362 quinquies of the Spanish Criminal Code penalises supplying doping substances to athletes without therapeutic justification, with prison sentences, fines and disqualification, within the framework of Spanish anti-doping legislation. In other words, buying and above all reselling is not a purely health matter.

In summary, and what you can do today

What you need to take away is simple: there is no legal website selling testosterone in Spain, and the main risk is not just the molecule, but a product with no batch number, no traceability and nobody keeping an eye on your haematocrit or your fertility. The alternative is not to give up: it is to do it by the route that does work, with a properly made diagnosis and reversible causes treated first.

That route exists in Spain today and it is the legal one: men's hormonal health treatment, with a prior assessment, a prescription from a registered doctor where appropriate, and ongoing follow-up with blood tests. At AiON we support that process. If you recognise yourself in the symptoms, the first step is to check whether you are eligible.