Mesterolone

Proviron, Provironum, Pro-Viron

Oral steroidsControlled substanceWADA S1.1 · prohibitedEvidence: approved medicine

An oral 1α-methyl DHT derivative that is not 17α-alkylated, so liver strain is minimal. A strong androgen but a weak anabolic; it cannot convert to estrogen.

What it gives

What people use it for and what the sources report. Strength is a general category from the literature: mild, clear or strong.

Purpose

Used alongside other steroids for libido, a harder look, and in the hope of curbing estrogen — the last has little evidence. Prescribed in many countries (not the US) for male androgen deficiency; a WHO trial found no clear benefit in male infertility.

What people seek and what studies show

Evidence for the effects users seek is thin. In an uncontrolled study of older men with symptoms of low testosterone, symptom scores improved while total testosterone, SHBG and estradiol fell. Trials in depressed men were mixed: as effective as amitriptyline in one, no better than placebo in another. It binds SHBG about four times more strongly than DHT; its muscle-building effect is weak.

Effects

Well-being & libidoHard, dry look

Evidence: Approved medicine — studied in people for its medical use

Sought effects by goal (as reported)

Cutting
Sought for: hard, dry look
Health
Sought for: well-being & libido
Works against it: worse cholesterol (HDL↓ LDL↑)

Possible side effects

Possible does not mean certain: whether they appear depends on dose, duration, individual response and monitoring. Below — what to watch for and how to notice it early.

10 possible side effects

level · how often it is reported
Moderate
Suppression of natural testosterone & fertility
Suppresses gonadotropins less than most AAS at medical doses, but higher doses do lower LH and testosterone.
How to notice: Lower libido and energy, smaller testicles; low natural testosterone on tests after stopping.
In women: Menstrual changes or missed periods, lower libido and energy; reduced fertility.
possible
Moderate
Worse cholesterol (HDL↓ LDL↑)
Can lower HDL, especially combined with other steroids; data specific to mesterolone are limited. Only a lipid panel shows the change.
How to notice: No symptoms — only visible on a lipid panel.
possible
Moderate
Androgenic hair loss
A DHT analogue that 5α-reductase inhibitors cannot block; it can accelerate genetic hair loss.
How to notice: More hair in the shower, thinning at the temples or crown.
possible
Moderate
Black-market quality risk (fakes, contamination)
Black-market tablets may be counterfeit or mislabeled.
How to notice: Unexpected effects, pain or infection, a stronger or weaker effect than expected.
possible
Moderate
Heart strain / heart-muscle thickening
No compound-specific data; it adds to the class link between years of AAS use and heart-muscle changes.
How to notice: Shortness of breath on effort, lower endurance, palpitations.
rare
MenLow
WomenHigh
Virilization in women (often irreversible)
Mainly androgenic for women: voice deepening, hair growth and clitoral enlargement may be permanent.
How to notice: Hoarse or deeper voice, new facial or body hair, menstrual changes, clitoral enlargement.
common
Low
Thick blood (hematocrit) / clot risk
Raises hemoglobin far less than testosterone: in men with low testosterone the rise was small and not significant; it can still add to the rise from other AAS.
How to notice: Often silent; sometimes headaches, flushed face, itch after a hot shower.
possible
Low
Prostate growth / PSA rise
Acts on the prostate like DHT: prostate growth and a PSA rise are possible; it is contraindicated in prostate cancer.
How to notice: More frequent urination or a weak stream, especially at night.
possible
Low
Acne, oily skin
Androgenic: oily skin and acne are possible.
How to notice: Oily skin, spots on back, shoulders and face.
possible
Low
Liver strain
Not 17α-alkylated: unlike most oral steroids, it has little or no potential to injure the liver.
How to notice: Usually silent early; later tiredness, nausea, itch, dark urine.
rare

What the levels mean

Lowbackground — just be aware
Moderatewatch for signs
Elevatedneeds regular control
Highcritical — can be life-threatening or permanent

Level: general category from the literature, not your personal risk

How often

common
reported often
possible
reported in some people
rare
reported occasionally

How to lower the risks

For 9 of 10 possible side effects there are specific ways to lower the chance: everyday measures, supplements and options a doctor may consider. For the rest — general advice. No measure removes a risk completely.

ModerateSuppression of natural testosterone & fertility

Check hormones before and after; if they stay low, see an endocrinologist.

Measure
Regular blood testsWorking with a doctor
How each option helps (2)
  • Regular blood tests — LH, FSH and testosterone show how deep suppression is and whether natural production has recovered afterwards.
  • Working with a doctor — Assesses how deep suppression is and guides recovery afterwards, including fertility testing.
ModerateWorse cholesterol (HDL↓ LDL↑)

Avoid combining several oral steroids; regular cardio, soluble fiber (psyllium), less saturated fat and alcohol; if LDL/ApoB stay high, a doctor may consider a statin. Omega-3 only lowers triglycerides.

Measure
Regular blood testsWorking with a doctorAvoiding alcohol and other liver stressorsRegular cardio training
How each option helps (8)
  • Regular blood tests — A lipid panel with ApoB shows how far HDL has dropped and LDL risen — changes you cannot feel.
  • Working with a doctor — Interprets lipids and ApoB and decides whether a statin or other therapy is warranted.
  • Avoiding alcohol and other liver stressors — Alcohol raises triglycerides; its small HDL bump does not lower heart risk.
  • Regular cardio training — Raises HDL a little and lowers triglycerides; it cannot offset a steroid-driven fall in HDL on its own.
  • Berberine — Placebo-controlled meta-analysis: LDL about 0.5 and triglycerides about 0.4 mmol/L lower; HDL unchanged. Trials are mostly small; no statin substitute.
  • Citrus bergamot — Pooled small trials show lower LDL and triglycerides, but certainty is low to very low; it is no replacement for statins.
  • Omega-3 (fish oil, EPA/DHA) — Clearly lowers triglycerides but does not fix the steroid HDL drop, the main lipid harm; DHA-containing oils may even raise LDL slightly.
  • Psyllium husk fiber — Lowers LDL by about 0.2–0.3 mmol/L (roughly 5–10%), also on top of doctor-prescribed statins; no effect on HDL.
ModerateAndrogenic hair loss

Ketoconazole shampoo, minoxidil, a dermatologist early if you are prone to it.

Supplement or OTC product
How each option helps (1)
  • Minoxidil (topical) — Slows thinning and regrows some hair; scalp itching and early temporary shedding are common, unwanted facial hair possible. Gains fade once stopped.
ModerateBlack-market quality risk (fakes, contamination)

Products obtained without a prescription are often fake, mislabeled or non-sterile, and there is no way to check at home. For legal supplements, look for third-party testing (Informed Sport, NSF).

ModerateHeart strain / heart-muscle thickening

Regular cardio, blood pressure control, an echo as a baseline and then yearly.

Measure
Heart screening: ECG and echocardiogramWorking with a doctorHome blood-pressure monitoringRegular cardio training
How each option helps (4)
  • Heart screening: ECG and echocardiogram — Echocardiography shows wall thickening and reduced pumping early, while stopping AAS and treating BP can still help.
  • Working with a doctor — Orders ECG and echocardiography and treats early heart changes.
  • Home blood-pressure monitoring — Keeping BP controlled is one of the main ways to limit heart-wall thickening.
  • Regular cardio training — Supports heart and vessel function, but does not reverse steroid-related heart thickening or weakening.
MenLow
WomenHigh
Virilization in women (often irreversible)

Stop at the first voice change and see a doctor — early stopping matters.

Measure
Working with a doctor
How each option helps (1)
  • Working with a doctor — Steroid labels say to stop at the first mild signs (hoarse voice, facial hair, clitoral growth) to prevent permanent change; checks catch them early but do not make use safe.

Low-level side effects

Hematocrit
Check the blood count regularly; if hematocrit stays high, a doctor decides — usually stopping or reducing the cause, sometimes therapeutic phlebotomy, never blood-bank donation. Avoid dehydration: it thickens the blood further.
Measure
Regular blood testsTherapeutic phlebotomy prescribed by a doctorWorking with a doctor
How each option helps (3)
  • Regular blood tests — A blood count shows hematocrit and hemoglobin climbing toward the range where clot and stroke risk rises.
  • Therapeutic phlebotomy prescribed by a doctor — Only on a doctor's decision, never at a blood bank. Lowers hematocrit quickly but temporarily; repeated sessions drain iron, and a lower clot risk is unproven.
  • Working with a doctor — Manages thick blood by changing what you use or, if justified, by therapeutic phlebotomy.
Prostate
PSA as a baseline, especially after 40; a urologist if urination changes.
Measure
Regular blood tests
How each option helps (1)
  • Regular blood tests — PSA tracks prostate changes on androgens — most relevant after 40 or with urinary symptoms.
Acne
Gentle skin care, cleansing after training, a dermatologist if it spreads.
Supplement or OTC product
How each option helps (3)
  • Adapalene — Reduces spots in many users. Redness, scaling, dryness and stinging are common early and usually ease; acne may look worse at first. Rarely, allergic swelling.
  • Benzoyl peroxide — A first-line acne option. Dryness, redness and peeling are common at first; it bleaches hair and fabric; rarely, serious allergic reactions. Severe steroid acne needs a dermatologist.
  • Zinc — Trials show a modest drop in inflamed spots, weaker than antibiotics; steroid acne is driven by androgens.
Liver
No alcohol, no other liver stressors, limit oral steroids and their combinations, check liver enzymes.
Measure
Avoiding alcohol and other liver stressorsRegular blood tests
How each option helps (5)
  • Avoiding alcohol and other liver stressors — Removes a major extra liver stressor during oral steroids and other hepatotoxic drugs.
  • Regular blood tests — ALT, AST, GGT and bilirubin show liver strain before symptoms; heavy lifting alone raises AST/ALT for days, and GGT helps tell muscle from liver.
  • Ademetionine (SAMe) — Used for intrahepatic cholestasis in some countries, but trials are small and of low quality; untested in steroid users. Stopping the oral steroid matters most.
  • N-acetylcysteine (NAC) — Restores glutathione; proven in paracetamol poisoning and helped in early acute liver failure of other causes, but untested in steroid users.
  • TUDCA (tauroursodeoxycholic acid) — Improves bile flow in cholestatic disease; in steroid cholestasis only case reports, with failures in severe cases. Stopping the oral steroid matters most.

Check-ups and blood tests

Which tests and check-ups to do and when. This is a guide — agree the exact schedule with your doctor.

Baseline tests
your own starting values — every later result is compared with them
Lipid panel (HDL, LDL, triglycerides, ApoB)cholesterol, low estrogen
Complete blood count (hematocrit, hemoglobin)
Testosterone (total, free), LH, FSH, SHBGnatural testosterone
Estradiol (sensitive assay)low estrogen
PSA
Home blood-pressure logheart
ECGheart
Echocardiogram (heart ultrasound)heart
While taking
about 4–6 weeks in, then every 6–8 weeks — agree the exact schedule with your doctor
Lipid panel (HDL, LDL, triglycerides, ApoB)cholesterol, low estrogen
Complete blood count (hematocrit, hemoglobin)
Estradiol (sensitive assay)low estrogen
Home blood-pressure logheart
After stopping
4–8 weeks after stopping (later after long-acting injections), then until values return to baseline
Lipid panel (HDL, LDL, triglycerides, ApoB)cholesterol, low estrogen
Complete blood count (hematocrit, hemoglobin)
Testosterone (total, free), LH, FSH, SHBGnatural testosterone
Semen analysisnot earlier than 3 months after stopping, then every 3 months until normalnatural testosterone
Every year
with regular or repeated use
ECGheart
Echocardiogram (heart ultrasound)heart

Which doctors can help

Sports physiciancoordinates everything
Cardiologistcholesterol, heart
Endocrinologistlow estrogen, natural testosterone
Dermatologisthair loss
Gynecologistvirilization, natural testosterone (women)

At home

  • Home blood pressure: 2–3 times a week in the morning, keep a log

Get medical help at once if

  • Chest pain or pressure, breathlessness on light effort, swollen ankles, fainting — seek urgent care.
  • Deepening voice, new facial hair, clitoral enlargement — stop and see a doctor: changes can become permanent. (women)

In an emergency, call your local emergency number.

For women

For women it acts mainly as an androgen: little muscle benefit, but a real risk of voice deepening, hair growth and clitoral enlargement that may be permanent.

Myth & fact

Myth

“Proviron works as an anti-estrogen.”

Fact

No good human evidence shows it blocks aromatase or prevents gynecomastia. It just cannot become estrogen; DHT-like androgens may blunt estrogen in breast tissue, but that is no substitute for medical care.

Combinations

Overlap5α-reductase inhibitor with steroids it cannot affect

DHT-derived steroids, trenbolone and trestolone act without 5α-reductase, so finasteride and dutasteride do not lower their effect on hair or prostate; they only reduce DHT made from testosterone, while finasteride and dutasteride keep their own side effects.

DrostanoloneMetenolone1-TestosteroneOxandroloneStanozololOxymetholoneMethasteroneTrenboloneTrestoloneMethyl-1-testosterone (M1T)Desoxymethyltestosterone (DMT, Madol, Pheraplex)Epistane (methylepitiostanol, Havoc)ProstanozolMestanoloneStenbolone1-Andro (1-androsterone) and related prohormonesEpiandrosterone (Epi-Andro)Androstanolone (dihydrotestosterone, DHT)

Check combinations →

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