Prescription-only items from the list
13 drugs that appeared mixed in with supplements
Experimental material. Read before using anything from here.
Nothing on this page is a medical recommendation, prescription or treatment plan. It is an organized translation of protocols circulating in research communities and, where it exists, of what published trials tested. The two are marked differently — and they are not equivalent.
Most of the compounds here have no FDA approval for human use. Several are sold labeled "research use only", which means they have not gone through purity, sterility or dosage controls for human consumption. A community-reported dose is not a validated dose: it is what someone reported having done.
Talk to a licensed health professional before considering any of these compounds. If you already use one and feel anything unexpected, seek care — do not wait for the next routine test.
Summary
Anastrozole, letrozole, tamoxifen, clomiphene, mesterolone, DHEA, pregnenolone, metformin, finasteride, dutasteride, tadalafil and clenbuterol appeared on a list of supplements. They are not supplements: they are prescription drugs, several with oncology indications, one for veterinary use and one an anabolic steroid. This page says what each one is and why it requires a prescription — and gives no dosing, by decision.
Why these are kept separate
The twelve items on this page appeared mixed into a list of supplements. They are not supplements. They are medicines that require a medical prescription — several with oncology indications, one is a veterinary-use bronchodilator and another is an anabolic steroid.
This page says what each one is and why it requires a prescription. It gives no dosing, and that is deliberate. The dose of an aromatase inhibitor or an estrogen receptor modulator comes out of a consultation with lab results in hand, not from a table on a website.
Hormonal modulators
This is the group most used off-label in the context of bodybuilding and home-made hormone replacement. All alter the hormonal axis in a sustained way.
| Drug | What it is | Registered indication | Why it requires a prescription |
|---|---|---|---|
| Anastrozole | Non-steroidal aromatase inhibitor | Hormone-dependent breast cancer in postmenopausal women | Suppresses estradiol sharply. Estradiol that is too low costs bone density, lipid profile, libido and joints |
| Letrozole | Non-steroidal aromatase inhibitor, more potent than anastrozole | Breast cancer; ovulation induction in some protocols | Same class, even deeper suppression. Not interchangeable with anastrozole in practice |
| Tamoxifen | Selective estrogen receptor modulator (SERM) | Breast cancer, treatment and prevention | Risk of thromboembolism and endometrial hyperplasia. Requires screening and follow-up |
| Clomiphene (Clomid) | SERM, estrogen agonist and antagonist depending on the tissue | Ovulation induction in female infertility | Male use to raise testosterone is off-label. Visual disturbances are listed in the package insert |
| Mesterolone (Proviron) | Oral anabolic androgenic steroid | Male hypogonadism, in some countries | It is an anabolic steroid. Axis suppression, lipid profile and liver effects all count |
| DHEA | Prohormone precursor of testosterone and estradiol | Restricted use; in Brazil it is a controlled substance | Converts to sex hormones to a degree that varies between people. It is not a vitamin |
| Pregnenolone | Steroid precursor upstream of the entire axis | No established indication | It sits at the top of the steroid cascade: touching here moves everything below, in a poorly predictable way |
Cardiometabolic and urological
| Drug | What it is | Registered indication | Why it requires a prescription |
|---|---|---|---|
| Metformin | Biguanide; reduces hepatic glucose production and improves insulin sensitivity | Type 2 diabetes; polycystic ovary syndrome | Requires kidney function to be assessed. Lactic acidosis is rare and serious. Reduces vitamin B12 absorption with prolonged use |
| Finasteride | Inhibitor of 5-alpha-reductase type 2 | Benign prostatic hyperplasia; androgenetic alopecia | Persistent sexual effects are described and debated in the literature. Alters the PSA value, which interferes with prostate cancer screening |
| Dutasteride | Inhibitor of 5-alpha-reductase types 1 and 2 | Benign prostatic hyperplasia | Same class, broader suppression and a much longer half-life — weeks, not hours |
| Tadalafil | Phosphodiesterase type 5 inhibitor | Erectile dysfunction; prostatic hyperplasia; pulmonary hypertension | Potentially fatal interaction with nitrates. Requires cardiovascular assessment first |
| Clenbuterol | Beta-2 adrenergic agonist | Bronchodilator — in several countries, veterinary use only | Used off-label for fat loss. Tachycardia, arrhythmia, tremor and hypokalemia. Banned by WADA |
What to do with this page
- If one of them interests you, take the name to your doctor. That is literally what this page exists for: for you to arrive informed, not to self-medicate.
- None of them is a supplement, even when listed in a catalog next to vitamin D and creatine. The sales context does not change the nature of the molecule.
- Clenbuterol and mesterolone are banned by WADA. Anyone competing in federated sport has no margin here.
- Tadalafil with nitrates is the most dangerous interaction on this entire page. Anyone using nitrates for angina needs to know this before anything else.