Weight loss and performance enhancement
Clenbuterol has been observed to both increase muscle mass and reduce body fat. Additionally, it remains in the body with an active effect for up to about six days after consumption (detectable traces can remain longer). Because of these properties, it’s often used as a weight loss supplement or to enhance athletic performance.
People taking clenbuterol for weight loss or performance enhancement often use anabolic steroids or growth hormones as well.
Studies on the efficacy of clenbuterol as a weight loss or performance enhancer in humans are quite limited, although many studies have been performed in animals and livestock:
- ResearchersTrusted Source have observed that clenbuterol stimulates muscle growth and repair while preventing atrophy in mice and rats.
- StudiesTrusted Source in livestock have indicated that the increase in muscle growth occurs at the expense of fat tissue. This is part of a process referred to as repartitioning.
- A studyTrusted Source in horses found that long-term administration of high doses of clenbuterol increased the expression of genes related to various muscle components and fat metabolism.
Despite the fact that there is minimal evidence for clenbuterol as a performance-enhancing drug, it’s listed on the World Anti-Doping Agency’s (WADA) Prohibited List.
Clenbuterol can have negative side effects when overused or misused. These can include:
- increased heart rate
- rapid breathing
- heart palpitations
- chest pain
- electrolyte imbalance
A review of adverse reactions to clenbuterol reported to two poison control centers found that 11 of the 13Trusted Source cases were due to clenbuterol use for weight loss or bodybuilding.
Dosage and administration
When clenbuterol is taken to control asthma symptoms, the recommended dosage is between 0.02 and 0.03 milligrams per day. The medication comes in tablet or inhaler form for asthma treatment. Like many bronchodilators used for asthma treatment, you should use it as needed — up to the recommended dosage as opposed to regular daily use.
Clenbuterol used for weight loss or performance enhancement can be acquired as a tablet, liquid, or injection. People using clenbuterol for this purpose typically use between 0.06 and 0.12 milligrams per day, which is higher than the recommended dosage for asthma treatment.
Clenbuterol isn’t approved by the FDA for use in humans. Outside of the United States, it can be used to treat asthma or COPD. The drug is often used off-label for weight loss or to enhance athletic performance.
Clenbuterol is on the World Anti-Doping Agency’s (WADA) Prohibited List. Professional athletes testing positive for this drug can be disqualified from participating in competitive sports.
Clenbuterol can have negative side effects when overused or misused.
It’s important to strictly follow all dosage guidelines when using clenbuterol.