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Clenbuterol

Clenbuterol is an illegal beta-adrengic agonist used to beef up livestock (before a metabolite was found to be toxic). It is like ephedrine, except much more potent and stays in your body for a day rather than just 4 hours. It is a potent fat loss and muscle preservation agent with side effects.

Our evidence-based analysis on clenbuterol features 32 unique references to scientific papers.

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Last Updated:

Summary of Clenbuterol

Primary information, health benefits, side effects, usage, and other important details

Clenbuterol is a potent fat-burning compound with significant muscle preserving and building effects.

It was once used in feed animals to increase growth rates of lean mass. It is currently banned for over-the-counter sales and is typically seen as one of the compounds known as 'steroids' (the vague social term for it, as it is not a steroid structure) Despite the ban, it is still used amongst bodybuilding enthusiasts due to its potency.

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How to Take

Recommended dosage, active amounts, other details

Clenbuterol should be started at a dose of 20mcg. Higher doses can be used after tolerance is assessed but caution is warranted at higher doses due to the potency of the drug. Under no circumstance should one consume more than 120mcg a day.

Most clenbuterol should be taken in the AM hours, to allow some metabolism before sleep at night (although it will still be disturbed).

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Human Effect Matrix

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The Human Effect Matrix summarizes human studies to tell you what effects Clenbuterol has on your body, how much evidence there is, and how strong these effects are.

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Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
Notes
grade-c Notable - See study
The reduction in fat mass under the influence of clenbuterol is greater than that observed with other fat burners such as ephedrine or yohimbine
grade-c Minor - See study
Appears to increase muscle protein synthesis
grade-c Minor - See study
An increase in power output is noted with clenbuterol usage
grade-c Minor - See study
The rate of muscle protein breakdown is decreased with clenbuterol usage

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Things to Note

Is a Form Of

Primary Function:

Also Known As

Clen, 4-amino-alpha(t-butyl-amino)methyl-3, 5-dichlorobenzyl alcohol

Goes Well With

  • A sleep aid (Check out mood for options)

Caution Notice

Clenbuterol is a potent beta2-adrenergic agonist, exerting adrenaline-like effects on the body. Doses too high or combining with other supplements can result in cardiac arrythmia or sudden death.

Clenbuterol is also a restricted or illegal compound in certain areas of the world, and is banned for usage by athletes under most sports agencies.

Clenbuterol is highly stimulatory, and has a long half life (so will stimulate for quite some time)

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Click here to see all 32 references.