Clenbuterol, marketed in Italy as Monores and elsewhere as Spiropent, is a particularly potent long-acting β2 agonist used in the treatment of asthma. In addition to providing anti-asthma activity, this substance increases heart rate and promotes weight loss by also acting on β3 receptors. # 3 receptors are present in adipose tissue, and their activation determines lipolysis of fats.

Clenbuterol, taken in super-therapeutic doses, has been shown in numerous studies to increase muscle mass , therefore, it has anabolika kaufen online shop, the mechanism of action of which is not entirely clear. According to some scientists, this substance is able to block the activity of certain enzymes with protease properties, that is, to catabolize already deposited proteins, therefore, if this mechanism of action is confirmed, it turns out that clenbuterol has anti-catabolic activity and for this reason hypertrophy. muscle tissue. To confirm this theory, there would also be an obvious action against the catabolic activity of muscle tissue induced by glucocorticoids, in fact, Clenbuterol reduces the catabolic effects of cortisone drugs.

However, some studies show how dosages are used. over-therapy with this substance also hypertrophies the heart cells , which leads to greater risks to heart health. In addition, according to some studies, despite the increase in muscle mass, the use of clenbuterol does not lead to an improvement in athletic performance, in particular aerobic capacity, since some researchers suggest that cardiac hypertrophy after taking this substance reduces the ability of the heart to saturate muscles with oxygen, which impairs aerobic performance.

Another possible hypothesis explaining these effects is that clenbuterol is able to convert slow or intermediate fibers into fast fibers more capable of providing anaerobic rather than aerobic effort, in fact several studies have shown this property.

Another risk that is highlighted when taking clenbuterol is that at high doses, it induces apoptosis (programmed cell death) in heart muscle and skeletal muscle cells in various laboratory animals. This turns out to be a very dangerous side effect that users of high doses of this substance can experience. This effect has not yet been demonstrated in humans, but the animal tests that led to this are different.

The use of clenbuterol in sports is quite common, and numerous positive cases demonstrate this on doping tests. In recent years, cyclists, sprinters, tennis players and athletes from other sports have been tested positive for clenbuterol.

Clenbuterol, as mentioned, is also able to stimulate lipolysis by acting on the β3 receptors of adipocytes and increasing the heart rate for mild activity at β1 receptors. Several studies in horses (Kearns) show that it is especially effective in promoting weight loss in the first 2 weeks of treatment, after which its activity is significantly reduced due to the presumably form of tolerance to the substance caused by a decrease in the presence of membrane receptors. which develops after constant stimulation of the same.

This drug is especially prized by body builders for its pronounced anabolic and lipolytic properties, however, due to its growing use for non-therapeutic purposes, it has become a substance with increasingly limited control, and in some states it has also been banned from selling it.As a result of growing difficulties with While searching for this product, many users have recently turned to salbutamol, a similar substance with similar but probably inferior properties, but easier to find as the primary treatment for asthma in many states.

These are mainly strength athletes who use this substance, and, apparently, the dosages significantly exceed the therapeutic ones, in fact, clenbuterol is taken in doses ranging from 80 to 200 mcg per day to develop hypertrophy. loss of muscle mass and weight.

According to several studies, the constant use of this substance, like all β2-agonists, quickly leads to the suppression of β2-receptors, in essence, to the constant activation of these receptors in reducing the availability through cellular internalization of the same, therefore, continuous use leads to develop strong tolerance. For this reason, most non-therapeutic users of this substance use it for several days (2 to 4) and then stop taking it for an equivalent amount of time before resuming it. Then they repeat the cycle several times.

Zeranol, Zilpaterol, Ractopamine

These substances are β2-agonists used in zootechnics. These active ingredients have strong anabolic properties and are used in some countries for raising beef cattle. They work similarly to clenbuterol, but appear to be much more effective in stimulating muscle growth.

These compounds were recently discovered, and therefore there is little data on their properties, in particular, there are still no studies regarding their possible use in humans. However, athletes who are always mindful of new pharmacological discoveries have already had the opportunity to use these compounds to stimulate muscle growth and weight loss. Apparently, they have already been included in the list of substances prohibited by the anti-doping rules.


Formoterol is a long-acting β2-agonist (about 12 hours) used in inhalers for the treatment of asthma and obstructive airways disease. Some studies show that inhaling this product does not improve athletic performance, but it is still unclear if very high dosages can alter these results.