Clenbuterol Hydrochloride 40mcg Tablets BP Clen 40 combines the long-acting stimulant bronchodilator clenbuterol with caffeine (stimulant) and aspirin (adjuvant) for oral use. Clen 40 is a potent fat loss agent by agonizing beta-2-adrenergic receptors, resulting in increased metabolic activity. Clenbuterol is a sympathomimetic amine used by sufferers of breathing disorders as a decongestant and bronchodilator. People with chronic breathing disorders such as asthma use this as a bronchodilator to make breathing easier. It is most commonly available as the hydrochloride salt, clenbuterol hydrochloride. Clenbuterol is approved for use in some countries as a bronchodilator for asthma. Clenbuterol is a β2 agonist with some structural and pharmacological similarities to epinephrine and salbutamol, but its effects are more potent and longer-lasting as a stimulant and thermogenic drug.It is commonly used for smooth muscle-relaxant properties as a bronchodilator and tocolytic. It is classified by the World Anti-Doping Agency as an anabolic agent, not as a β2 agonist. Clenbuterol is prescribed for treatment of respiratory diseases for horses, and as an obstetrical aid in cattle.