Table of ContentsView AllTable of ContentsMedical UsesUses in BodybuildingHow It Is TakenSide EffectsPossible DangersIs Clenbuterol Illegal?
Table of ContentsView All
View All
Table of Contents
Medical Uses
Uses in Bodybuilding
How It Is Taken
Side Effects
Possible Dangers
Is Clenbuterol Illegal?
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What Is Clenbuterol?
Clenbuterol is classified as abeta2-agonistthat acts onsmooth (involuntary) musclesof the body, making them relax. It has similar properties to the drugalbuterolused for the treatment ofasthmaandchronic obstructive pulmonary disease (COPD)but is more potent and longer-acting.
In the United States, clenbuterol is not approved for use in humans and is currently only authorized for the treatment of asthma in horses.
Clenbuterol Use for Bodybuilding and Weight Loss
Clenbuterol exerts other properties when it binds to beta2 receptors. Among them, clenbuterol causesthermogenesis, meaning that it raises your body temperature and, doing so, helps burn fat.
For this reason, bodybuilders have been known to use clenbuterol just before competitions to burn excesssubcutaneous fatjust beneath the surface of the skin. By doing so, muscle striations are seen more clearly and the person’s physique is said to be more “cut.”
Rather, clenbuterol shares properties with PDEs like ephedrine and amphetamines that have stimulant properties. Like these banned substances, clenbuterol is known to increase thebasal metabolic rate,heart rate, and exercise output while acting as anappetite suppressant. Any increase in muscle mass is mainly attributed to the increased exercise output.
Because it does not have the masculinizing effects of a true anabolic substance (such asincreased facial and body hair, male pattern hair loss, and increases in bone mass), clenbuterol is especially popular among female athletes.
Due to its availability as a prescription bronchodilator in countries like Austria, China, France, Germany, Italy, Mexico, Portugal, and Spain, clenbuterol is sometimes illegally imported and sold online or as a street drug under the street name “clem.”
In the United States, it is only available in syrup form for use in horses and sold under the brand name Ventipulmin. Each one milliliter (mL) dose contains 0.0725 mg for clenbuterol.
When used illicitly, bodybuilders have been reported to take anywhere from 0.06 to 0.12 mg per day during the “cutting phase” of their training, often in tandem with other PDEs.
More concerningly, an injectable version of the drug called Planipart (used to relax the uterus of cattle during the birth of a calf) is available in certain countries, and there have been reports of its use among bodybuilders in online chat rooms.
In the United States, the use of clenbuterol has been restricted to horses due to side effects that may be severe in humans. For this same reason, drugs like Planipart are not used in the U.S. as the drug can be passed to humans through meat.
Common side effects of clenbuterol include:
Side effects tend to develop soon after a dose (between 30 minutes to three hours) and may only fully resolve two to six days later, depending on the dose and your body size.
Clenbuterol places extreme stress on the cardiovascular system due to its stimulant effects, and, even in horses, the drug is contraindicated for use in those with heart problems.The fact that bodybuilders often take more than the recommended dose places them at even greater risk.
Some of the possible risks of clenbuterol overuse include:
In 2021, Odalis Santos Mena, a Mexican fitness influencer, died after suffering cardiac arrest while undergoing an alternative therapy forunderarm sweatinginvolving clenbuterol and anesthesia.
Even so, its use in the United States is illegal, and the FDA warns that any veterinarian who sells or distributes clenbuterol in any form is in violation of federal law and may be subject to prosecution.
With that said, low levels of clenbuterol do not automatically disqualify an athlete if they live in a country where the drug is used in livestock. In such cases, it is possible to test positive for clenbuterol due to the consumption of tainted red meat.
Summary
Clenbuterol is a drug used as a prescription bronchodilator in some countries, but one that has become associated with doping among bodybuilders and athletes. When used as a performance-enhancing drug, clenbuterol burns body fat, suppresses appetites, and increases exercise output.
11 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Drug Enforcement Administration.Clenbuterol.Willson, C.Clenbuterol. In:Reference Module in Biomedical Sciences. Amsterdam (Neth): Elsevier; 2015. doi:10.1016/B978-0-12-801238-3.99481-9Jessen S, Solheim SA, Jacobson GA, et al.Beta2-adrenergic agonist clenbuterol increases energy expenditure and fat oxidation, and induces mTOR phosphorylation in skeletal muscle of young healthy men.Drug Test Anal.2020 May;12(5):610-618. doi:10.1002/dta.2755Hackett D.Training, supplementation, and pharmacological practices of competitive male bodybuilders across training phases.J Strength Condition Res.2022;36(4):963-970. doi:10.1519/JSC.0000000000003989PRBuzz.Clenbuterol weight loss Hollywood secret.The Independent.Clenbuterol: the new weight-loss wonder drug gripping Planet Zero.DailyMed.Ventipulmin - clenbuterol syrup.European Union.Planipart 0,03 mg/ml solution injectable pour bovins.World Anti-Doping Agency.WADA responds to questions received from New York Times related to clenbuterol cases involving Chinese swimmers.International Hyperhidrosis Society.What went wrong?American Veterinary Medical Association.FDA warns that compounding clenbuterol is illegal.
11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Drug Enforcement Administration.Clenbuterol.Willson, C.Clenbuterol. In:Reference Module in Biomedical Sciences. Amsterdam (Neth): Elsevier; 2015. doi:10.1016/B978-0-12-801238-3.99481-9Jessen S, Solheim SA, Jacobson GA, et al.Beta2-adrenergic agonist clenbuterol increases energy expenditure and fat oxidation, and induces mTOR phosphorylation in skeletal muscle of young healthy men.Drug Test Anal.2020 May;12(5):610-618. doi:10.1002/dta.2755Hackett D.Training, supplementation, and pharmacological practices of competitive male bodybuilders across training phases.J Strength Condition Res.2022;36(4):963-970. doi:10.1519/JSC.0000000000003989PRBuzz.Clenbuterol weight loss Hollywood secret.The Independent.Clenbuterol: the new weight-loss wonder drug gripping Planet Zero.DailyMed.Ventipulmin - clenbuterol syrup.European Union.Planipart 0,03 mg/ml solution injectable pour bovins.World Anti-Doping Agency.WADA responds to questions received from New York Times related to clenbuterol cases involving Chinese swimmers.International Hyperhidrosis Society.What went wrong?American Veterinary Medical Association.FDA warns that compounding clenbuterol is illegal.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Drug Enforcement Administration.Clenbuterol.Willson, C.Clenbuterol. In:Reference Module in Biomedical Sciences. Amsterdam (Neth): Elsevier; 2015. doi:10.1016/B978-0-12-801238-3.99481-9Jessen S, Solheim SA, Jacobson GA, et al.Beta2-adrenergic agonist clenbuterol increases energy expenditure and fat oxidation, and induces mTOR phosphorylation in skeletal muscle of young healthy men.Drug Test Anal.2020 May;12(5):610-618. doi:10.1002/dta.2755Hackett D.Training, supplementation, and pharmacological practices of competitive male bodybuilders across training phases.J Strength Condition Res.2022;36(4):963-970. doi:10.1519/JSC.0000000000003989PRBuzz.Clenbuterol weight loss Hollywood secret.The Independent.Clenbuterol: the new weight-loss wonder drug gripping Planet Zero.DailyMed.Ventipulmin - clenbuterol syrup.European Union.Planipart 0,03 mg/ml solution injectable pour bovins.World Anti-Doping Agency.WADA responds to questions received from New York Times related to clenbuterol cases involving Chinese swimmers.International Hyperhidrosis Society.What went wrong?American Veterinary Medical Association.FDA warns that compounding clenbuterol is illegal.
Drug Enforcement Administration.Clenbuterol.
Willson, C.Clenbuterol. In:Reference Module in Biomedical Sciences. Amsterdam (Neth): Elsevier; 2015. doi:10.1016/B978-0-12-801238-3.99481-9
Jessen S, Solheim SA, Jacobson GA, et al.Beta2-adrenergic agonist clenbuterol increases energy expenditure and fat oxidation, and induces mTOR phosphorylation in skeletal muscle of young healthy men.Drug Test Anal.2020 May;12(5):610-618. doi:10.1002/dta.2755
Hackett D.Training, supplementation, and pharmacological practices of competitive male bodybuilders across training phases.J Strength Condition Res.2022;36(4):963-970. doi:10.1519/JSC.0000000000003989
PRBuzz.Clenbuterol weight loss Hollywood secret.
The Independent.Clenbuterol: the new weight-loss wonder drug gripping Planet Zero.
DailyMed.Ventipulmin - clenbuterol syrup.
European Union.Planipart 0,03 mg/ml solution injectable pour bovins.
World Anti-Doping Agency.WADA responds to questions received from New York Times related to clenbuterol cases involving Chinese swimmers.
International Hyperhidrosis Society.What went wrong?
American Veterinary Medical Association.FDA warns that compounding clenbuterol is illegal.
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