Proviron – Proper Labs [50tab/25mg]

Proviron Proper Labs for sale in the UK

Proviron by Proper Labs is an oral mesterolone tablet used as an on-cycle ancillary to bind SHBG, raise free testosterone and add hardness to the physique on aromatising cycles. If you want to buy Proviron UK from a verified source, each pack of 50 tablets at 25 mg sold here is lab-tested and shipped same working day from our UK warehouse.

What is Mesterolone?

Mesterolone is a synthetic oral androgen derived from dihydrotestosterone (DHT), originally developed by Schering in the 1930s and brought to market as Proviron in 1967 for the clinical management of androgen deficiency and certain fertility indications. Unlike most oral androgens, mesterolone is 1-methylated rather than 17-alpha-alkylated, so it is not classified as hepatotoxic in the same way as Dianabol, Anadrol or Winstrol. Its active half-life is roughly 12–13 hours, which is why daily dosing is standard and many users split intake across the day for steady plasma levels. Because mesterolone is DHT-derived, it cannot aromatise to estrogen and carries no water-retention or gynecomastia risk. It binds tightly to sex hormone-binding globulin (SHBG), freeing up bound testosterone, and shows mild competitive activity at the aromatase enzyme.

Proviron benefits

• Lowers SHBG and increases free, biologically active testosterone on cycle
• Adds visible hardness, density and definition to the physique
• Restores libido and erectile function during heavily suppressive cycles
• Mild anti-estrogenic effect supports compounds like testosterone or Dianabol
• Not 17-alpha-alkylated — no significant hepatic load at standard doses

Mesterolone is a support compound, not a mass-builder. The aim is to make the rest of your cycle work better by improving the free fraction of testosterone and dialling in the look of the physique.

Proviron dosage and cycle

Beginners: 25 mg/day. Intermediate: 50 mg/day. Advanced / contest prep: 75–100 mg/day. Daily dosing is standard, often split into two or three administrations to maintain stable blood levels through the day. Proviron is typically run for the duration of the cycle (8–12 weeks) alongside testosterone or oral compounds rather than on its own. It is not recommended for women due to virilisation risk at active doses. Onset is gradual — most users notice firmer-feeling muscle and improved libido within the first week to ten days.

Side effects and PCT

Proviron is well tolerated at standard doses. Because it is not 17-alpha-alkylated, hepatotoxicity is not a meaningful concern at clinical doses. The main caveats are androgenic: it can accelerate male-pattern hair loss in genetically susceptible users, may cause oily skin or mild acne, and should be approached cautiously by men with prostate concerns. Mesterolone is not a SERM and is not an aromatase inhibitor — it does not replace Arimidex (Anastrozole) for estrogen control on heavily aromatising cycles, and it is not a substitute for Nolvadex (Tamoxifen) during PCT. A standard SERM-based PCT after the host cycle is still required.

Stacks well with

Proviron is most commonly run alongside a testosterone base such as Test E 300 from Proper Labs to free up bound test and harden the look of a bulking or recomp cycle. For the alternative brand of the same compound, see our Pharmaqo Proviron 25mg.

Frequently asked questions

How long does Proviron take to start working?

Most users notice improved libido and a slightly firmer-feeling physique within the first seven to ten days, with the SHBG-lowering effect on free testosterone building over two to three weeks. Splitting the daily dose into two or three administrations keeps plasma levels steady due to the 12–13 hour half-life and tends to produce smoother results.

Is Proviron suitable for first-time users?

Proviron is well tolerated and not hepatotoxic at standard doses, but it is a support compound rather than a stand-alone cycle. First-time users typically run it alongside a testosterone base rather than on its own. Women should not use Proviron at performance doses due to the risk of virilisation from a strongly androgenic DHT derivative.

Can Proviron be detected on a drug test?

Yes. Mesterolone metabolites are detectable in urine for approximately six weeks after the last dose with standard WADA-style GC-MS testing. Anyone subject to sport or workplace drug testing should plan accordingly — a moderate half-life does not mean a short detection window.