Clenbuterol is a chemical called a beta-2-adrenergic agonist. It has approval in the United States for use in horses with breathing difficulty. It works by relaxing the airways in the animals’ lungs.

Clenbuterol is both a decongestant and a bronchodilator. A decongestant works by narrowing and constricting blood vessels to reduce congestion. Conversely, a bronchodilator helps relax the muscles around the airway, which in turn opens it up.

In some European and Latin American countries, clenbuterol has approval for human use as an asthma drug. However, in the U.S, it is banned to use it for this purpose.

The drug is also controversial because of its use in bodybuilding and weight-loss programs.

In this article, we take a look at how clenbuterol works, its uses, and what the risks are for people who take it.

What does clenbuterol do

Why do people use clenbuterol?

Clenbuterol’s initial use was as an asthma drug. However, bodybuilders, performance athletes, and those wanting to lose weight are now using it.

People can use clenbuterol as a weight loss aid because it can increase a person’s metabolism. As well as reducing body fat and weight, it also allows the user to retain both muscle mass and body strength at the same time.

Clenbuterol became known as a celebrity diet secret because of its apparent use by celebrities and famous athletes.

One study reviewed data from two regional poison centers in the U.S. It found that in 11 of the 13 reported casesTrusted Source of those taking clenbuterol, people had used it for weight loss reasons or as part of a bodybuilding program.

The World Anti-Doping Agency has banned the use of clenbuterol at all times, both in and outside of competition.

Clenbuterol dosage

Athletes and bodybuilders taking clenbuterol will often work on a program cycle that includes on and off periods.

The dosage can vary depending on factors that include gender and tolerance. People can take it orally or via injection, but both methods carry risks. Injections can cause scarring or air bubbles to form in the blood, while oral tablets can affect the liver.

When people use it in Europe and Latin America to open the airways in those with asthma, the recommended dose is 0.02 to 0.04 milligrams daily.

Clenbuterol risks and side effects

Clenbuterol is banned in many countries and has become so controversial because it has links to many side effects.

Many of these side effects are the same as those relating to amphetamines, including:

  • anxiety
  • shaking
  • headaches
  • atypical sweating
  • raised body temperature

Clenbuterol can also negatively affectTrusted Source the heart, causing some symptoms such as heart palpitations, atrial fibrillation, which is an irregular and often fast heartbeat, and problems with blood pressure.

Increased heart rate and dilation from using the drug can lead to cardiac hypertrophy. This condition is when the heart grows to an atypical size, which in turn can lead to a heart attack and eventually death.

Many countries have banned clenbuterol from being used in animals that humans will consume.

In 1994Trusted Source, 140 people in Spain required hospitalization after eating meat containing clenbuterol. Similarly, in 2006, 336 people in China were poisoned after eating pork that contained it.

Clenbuterol can reduce the amount of naturally occurring potassium in the body. Consequently, those taking it as a drug will often also eat extra portions of bananas to replace the substance.

Athletes will often combine taking clenbuterol alongside a diet high in protein, moderate in carbohydrates, and low in fat.