Final answer:
Ephedrine and clenbuterol are substances used for fat loss. Ephedrine increases metabolic rate and was part of the banned ECA stack, while clenbuterol is used off-label for its fat-burning effects despite being a bronchodilator.
Step-by-step explanation:
Ephedrine and clenbuterol are used for fat loss. They are known for their thermogenic effects, which means they can increase the body's temperature and metabolic rate, leading to increased burning of body fat. Ephedrine, which comes from the herb ephedra, was traditionally used in many weight loss supplements, often as part of the "ECA stack" alongside caffeine and aspirin. However, due to safety concerns, the FDA banned ephedrine for use in weight loss formulas in 2004. Despite their fat loss capabilities, ephedrine can also lead to several side effects such as decreased appetite, increased blood pressure and heart rate, sleeping problems, hallucinations, anxiety, and chemical dependence. Clenbuterol is another drug commonly used for fat loss, although it is not approved for this use in many countries. It is a sympathomimetic amine used by sufferers of breathing disorders as a decongestant and bronchodilator. People with chronic breathing disorders such as asthma use it as a bronchodilator to make breathing easier. However, some people use clenbuterol off-label for its fat-burning properties.