Winstrol (Stanozolol)
Stanozolol · Winny
Stanozolol, marketed as Winstrol (oral) and Winstrol Depot (injectable), is a synthetic anabolic-androgenic steroid derived from dihydrotestosterone (DHT). It is a C17-alpha-alkylated compound with a pyrazole ring fused to the A-ring of the steroid nucleus, which gives it unusual structural and pharmacologic properties: it is active orally AND injectably, and both forms are 17-aa (so both carry hepatotoxic potential, even the injectable). Developed by Winthrop Laboratories in 1962, it was historically FDA-approved for conditions including hereditary angioedema and catabolic states.
Starting dose. Oral 25mg/day OR Injectable 50mg EOD
Oral: split daily dose AM/PM given the ~9 hour half-life. Injectable (aqueous): inject daily or every other day - post-injection pain is common and some users shake vigorously before draw. Always plan liver enzyme monitoring (ALT/AST, GGT) pre, mid-cycle, and post.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
Stanozolol binds the androgen receptor (AR) with moderate affinity and drives protein synthesis, nitrogen retention, and red blood cell production. As a DHT derivative, it does not aromatize to estrogen and therefore has negligible estrogenic side-effect profile (no water retention, no gynecomastia from stanozolol itself).
It also binds sex-hormone binding globulin (SHBG) with high affinity, reducing circulating SHBG and raising free testosterone from any co-administered testosterone base. This contributes to the hardening effect when stacked with testosterone during a cut.
The C17-alpha-alkyl group protects the molecule from first-pass hepatic metabolism and gives both the oral and injectable forms significant hepatotoxic potential - the injectable IS 17-aa despite being injected, which is a common misconception. The aqueous suspension form of the injectable also causes significant post-injection pain at the injection site. Endogenous testosterone is suppressed via HPT-axis feedback.
What to expect
First 1-2 weeks: subtle drying effect, possible joint stiffness. Strength gains begin to appear by end of week 2.
Weeks 3-5: peak hardening and conditioning effect visible. Strength plateau forms. Liver enzymes should be checked mid-cycle.
Weeks 6-8: sustained gains, diminishing return beyond this point. Hepatic and joint risk accumulates. Most users cycle off at 8 weeks maximum.
Evidence
References for this compound are being re-checked against their source records. We are not showing them until each one is confirmed to support the claim it sits under.
Side effects & safety
Commonly reported
- Joint dryness and stiffness
- Elevated liver enzymes (ALT/AST) - both oral and injectable forms
- Suppression of endogenous testosterone
- Lipid shift (HDL drop, LDL rise - often severe with Winstrol)
- Injection site pain (injectable form - aqueous suspension)
Less common & notes
- Tendon injury risk (anecdotal - associated with dry joint state + rapid strength gains), acne, oily skin, accelerated hair loss in genetically predisposed users, mood changes, elevated blood pressure, headache.
- Women: virilization signs (voice deepening, clitoral enlargement, facial hair) at doses above 10mg/day - stop immediately if these appear.
- Rare but serious: cholestatic jaundice, hepatic adenoma or peliosis hepatis with prolonged or supratherapeutic use, significant cardiovascular strain from severe lipid shifts.
Pharmacokinetics
Oral ~9 hours | Injectable ~24 hours
Oral 1-2 hours | Injectable 4-6 hours
Oral 1-2 days | Injectable 3-4 days
Oral ~90% | Injectable ~100% IM
Oral 8-12 hours | Injectable 18-24 hours per dose
Hepatic (CYP3A4). Renal excretion of metabolites.
Storage. Oral: store at controlled room temperature (20-25°C / 68-77°F), protect from moisture. Injectable: store at controlled room temperature, do NOT refrigerate or freeze (aqueous suspension separates). Shake vigorously before drawing - microcrystals settle quickly. Use a 22-23G needle for draw/inject (finer needles clog). Keep out of reach of children and in a locked location - Schedule III controlled substance in the United States.
Regulatory status
Schedule III controlled substance in the United States under the Anabolic Steroids Control Act of 1990. Originally FDA-approved (brand name Winstrol, Winstrol Depot); the oral form was withdrawn from the US market in 2003 for commercial reasons but international approval remains in some jurisdictions. Possession or distribution without a valid prescription is a federal offense in the United States.
Put it to work
Calculate, log & track
Open Winstrol (Stanozolol) straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open Winstrol (Stanozolol) in the app →Go deeper
The guide & community
The complete Winstrol (Stanozolol) walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
Join the community ↗