Clenbuterol is well known as a potent weight loss and fat burning supplement. Used by both athletes during contest preparation and non-steroid users as an effective weight-loss tool, it remains among the favourite for weight control. It is classified as a β2-adrenergic receptor agonist rather than an anabolic steroid. Used in the medical field to treat breathing disorders, it has a bronchodilator and secretolytic effect, causing positive chronotropic and inotropic effects.