What is Turinabol?
Turinabol (chlorodehydromethyltestosterone, Tbol) is an oral, 17a-alkylated testosterone derivative with an extra chlorine atom that blocks aromatization. It is considered mild to moderate and delivers dry, well-retained gains without water retention. Historically it is known as a central agent of East German state doping.
This information is for research and educational purposes only. No medical advice.
Comparison
Oral anabolic steroids in the lexicon
All act on the androgen receptor. They differ in the core structure, as stated in the TPD lexicon. Tap a card to open its entry.
Turinabol is methandienone with a chlorine atom at position 4. According to the entry this prevents conversion to estrogen. 5
How it works
Turinabol activates the androgen receptor and does not aromatize to estrogen due to the chlorine atom. It has a low androgenic profile. Hence no estrogen side effects, no water - gains look dry and defined but come more slowly than with dianabol.
Where it acts
Where Turinabol acts
Tap a point or a card. Colour = androgen receptor, grey = observed. Values for anabolic steroids in general.
- Skeletal muscle
More strength and lean mass, new and thicker muscle fibres2
AR - Testes
Own testosterone production reduced, sometimes for months2
AR - Blood and vessels
HDL falls, blood pressure rises2
Observed in trials - Adrenal gland
In the lab broken down by hormone-making enzymes that it also inhibits7
Observed in trials
Known targets1
Compound PubChem CID 98521: one described target, Agonist (like all anabolic steroids).
- Gene
- AR
- UniProt
- P10275
- ChEMBL
- CHEMBL1871
- Action
- Agonist (like all anabolic steroids)
Use and dosing
Dosing
Dosing, titration and syringe
Loading the dosing information …
- Getting started and stepping up, drawn as a staircase
- Units on the U-100 syringe for every step
- How long one vial lasts
What the research shows
Compound-specific human studies are scarce. The AAS pharmacology (Kicman 2008, Hartgens & Kuipers 2004) describes the properties of oral, non-aromatizing 17a-alkylated steroids.
Study results
What the trials measured
Interactive: switch tabs, tap points, show or hide arms. Arms are named relative to each other, no dosing advice.
How long one tablet stayed detectable3
5 healthy men, a single dose, urine collected over 60 days
Values from the abstract. Which breakdown product stayed detectable longest differed from person to person. The study served doping analysis, not effects.
Strength gain on anabolic steroids2
Review of studies with athletes, compared with initial strength
Range from the abstract for anabolic steroids in general, not Turinabol specifically. According to the review, study doses were mostly below what is taken in sport.
Gain in body weight2
Review of studies with athletes
Range from the abstract for anabolic steroids in general. According to the review, fat mass did not decrease.
Research status
Where the research stands
ClinicalTrials.gov lists no trial with Turinabol. The data on this page come from a controlled single dose for doping analysis, from lab experiments and from reviews. As of 26 Oct 2026. 8
- Preclinical Lab experiments on breakdown by adrenal enzymes
- Phase 1 no registered trial
- Phase 2 no registered trial
- Phase 3 no registered trial
- Approval in East Germany from the 1960s
The approval predates today's trial registries, so the register shows no current trial for this form. 8
Side effects
- Liver: 17a-alkylated, ALT/AST can rise - liver support, limited duration.
- Lipids: can lower HDL.
- HPTA suppression - PCT topic.
- No estrogen side effects.
Storage
Store dry and cool, protected from light. Out of reach of children.
