Clenbuterol is a sympathomimetic amine that belongs to the class beta 2 adrenergic agonist. It works by binding to beta-2 adrenergic receptors found in smooth muscles. Activation of these receptors stimulates adenyl cyclase that catalyzes the conversion of ATP into cAMP. Consequently, increased levels of cAMP caused the relaxation of smooth vessels. Further, it stimulates the central nervous system and raises blood pressure and heart rate.

It was first developed by a German pharmaceutical company in the late 1970s. It was marketed under the brand name Ventipulnim as a bronchodilator. Later researchers found it can enhance athletic performance and aid weight loss. Clenbuterol is banned by World Anti-Doping Agency (WADA). Further, it is not approved by FDA for use in humans. The liquid form of clenbuterol is approved for the treatment of airway obstruction in horses. At Element Sarms, clenbuterol for sale is restricted to educational and research purposes.

From Pubchem

IUPAC Name:1-(4-amino-3,5-dichlorophenyl)-2-(tert-butylamino)ethanol
Synonyms: Planipart, Clenbuterolum,
Molecular Formula: C12H18Cl2N2O
Molecular Weight: 277.19 g/mol
CAS Number: 37148-27-9
PubChem CID: 2783

1. Clenbuterol and Muscle mass

Clenbuterol has been shown to improve muscle mass through the activation of beta-adrenergic receptors. One study in rats found that clenbuterol (4mg/kg) administration resulted in a significant increase in gastrocnemius muscle mass, protein, and RNA content and a decrease in epididymal fat pad mass. Further, researchers noticed that selective beta 2 antagonists and high doses of propranolol inhibited these effects. This indicates that clenbuterol's muscle-building effects occur through the activation of beta-adrenergic receptors [1].

Another study on Fischer rats confirmed these results. Researchers administered clenbuterol and salbutamol via implanted osmotic minipump at doses of 1.03 mg and 600μg per kilogram per 24 hours for 3 weeks. Both drugs increased muscle weight and protein content in young and old rats. However, salbutamol had similar muscle effects but smaller protein effects compared to clenbuterol. Both drugs could potentially help elderly people with muscle loss [2]. Furthermore, one small randomized controlled study in humans found that clenbuterol administration led to a significant increase in lean muscle mass and lean/fat ratio [3].

2. Clenbuterol and Weight Loss

Several fitness enthusiasts misuse clenbuterol for achieving weight loss. However, there are limited studies on the efficacy of clenbuterol for weight loss in humans. One study was conducted on horses to look at the weight loss effect of clenbuterol. Subjects received either clenbuterol (0.8ug/kg) or corn soup for 21 days. The researchers found a significant decrease in fat loss (12% in working horses and 8% in non-working horses) [4].

Clenbuterol is a thermogenic stimulant which means it increases the production of heat by the body, resulting in increased utilization of calories. Moreover, it has a lipolytic action and converts triglycerides into free fatty acids. One study found that clenbuterol ingestion increased energy expenditure by 21% and fat oxidation by 39% in young men [5].

3. Clenbuterol and Asthma

Clenbuterol has already been approved for the treatment of COPD in horses. In some countries, it is used to treat asthma in humans. One study was conducted to check the effectiveness of clenbuterol in children with moderate to severe asthma. Results found that the drug has a significant bronchodilator effect as compared to placebo, suggesting that a single dose of 1.0μg/kg is most advisable in children to treat asthma [6].

Furthermore, a 5-week study compared the effects of clenbuterol and terbutaline in patients with chronic airway obstruction. Researchers administered oral clenbuterol (20-30μg, 3 times daily) or oral terbutaline (2.5-5 mg, 3 times daily) to subjects. Both drugs significantly improved baseline lung function (FEV1) and had similar bronchodilator effects. Clenbuterol showed promise as an alternative oral treatment for chronic airway obstruction [7].

4. Summary

Clenbuterol is a beta-2 adrenergic agonist and has sympathomimetic activity. It has been studied for its effect on weight loss, muscle mass and COPD. Although its efficacy is not confirmed in humans, people abuse it to enhance athletic performance and lose weight. We don’t support its unwarranted use. At Element Sarms, clenbuterol purchase is restricted to research and educational purposes. Only buy clenbuterol if you are a qualified researcher.

1. Choo, J.J., M.A. Horan, R.A. Little, and N.J. Rothwell, Anabolic effects of clenbuterol on skeletal muscle are mediated by beta 2-adrenoceptor activation. American Journal of Physiology-Endocrinology and Metabolism, 1992. 263(1): p. E50-E56.
2. Carter, W.J. and M.E. Lynch, Comparison of the effects of salbutamol and clenbuterol on skeletal muscle mass and carcass composition in senescent rats. Metabolism, 1994. 43(9): p. 1119-1125.
3. Kamalakkannan, G., et al., Clenbuterol Increases Lean Muscle Mass but Not Endurance in Patients With Chronic Heart Failure. The Journal of Heart and Lung Transplantation, 2008. 27(4): p. 457-461.
4. Nolen-Walston, R.D., et al., Effect of long-term oral administration of a low dosage of clenbuterol on body fat percentage in working and nonworking adult horses. Am J Vet Res, 2015. 76(5): p. 460-6.
5. Jessen, S., et al., Beta2-adrenergic agonist clenbuterol increases energy expenditure and fat oxidation, and induces mTOR phosphorylation in skeletal muscle of young healthy men. Drug Testing and Analysis, 2020. 12(5): p. 610-618.
6. Boner, A.L., et al., Bronchodilating activity of oral clenbuterol in asthmatic children after single administration of different dosages. Pediatric Pulmonology, 1987. 3(1): p. 34-37.
7. Brusasco, V., E. Crid, S. Mangini, and C. Vibelli, A clinical trial of oral clenbuterol (NAB 365) in chronic airways obstruction. Current Medical Research and Opinion, 1980. 6(7): p. 449-455.