Meltos (active agent: clenbuterol) is a stimulant belonging to the sympathomimetic class of compounds, not an anabolic steroid. In bodybuilding, clenbuterol is most commonly utilized for cutting, pre-contest, and fat loss cycles. Clenbuterol can bind to receptors on fat cells and initiate lipolysis. This effect involves its interaction with beta-2 adrenergic receptors in fat tissue. Clenbuterol was originally a medication prescribed as a bronchodilator in the treatment of asthma. Through the activation of beta-2 receptors in the cell lining of the bronchial tubes, clenbuterol initiates bronchial dilation (the opening and expanding of the airways) in the lungs, nose, and throat. 

An important point to note is that continued and consistent use of clenbuterol will cause downregulation of beta-2 receptors, an effect that occurs very quickly in response to constant stimulation. The result of this effect is that fat loss diminishes during use and can reach a complete stop. There are two methods of remedying this effect. The first is to take time off from use of the drug for at least 2 weeks. The second is through the use of Ketotifen, an anti-histamine drug that is known for upregulating beta-2 receptors. 

Clenbuterol is not an anabolic steroid; it does not express or exhibit any of the known side effects that are associated with anabolic steroids. Instead, clenbuterol has the side effects and associated health risks that are common to all drugs in the stimulant class. Another commonly reported side effect is muscle cramping, caused by clenbuterol’s depletion of taurine in the body. Taurine, along with magnesium, potassium, and sodium, play crucial roles in the regulation of bioelectrical nerve impulses and signals that govern the contraction and relaxation of all muscle tissue types. When taurine is depleted, involuntary and often intense and painful muscle contractions that lead to cramps can result. Supplementation with taurine at 2.5–5 grams per day can help mitigate this side effect. 

WARNING: Clenbuterol may adversely affect the cardiovascular system and raise heart rate and/or blood pressure. Please consider this seriously and take it into account prior to use. Other common clenbuterol side effects include tremors, insomnia, sweating, and nausea. 

WARNING: Do not exceed recommended dosages! The dosage of clenbuterol must be slowly ramped up over the course of several days. The initial dosage should not exceed 20–40 mcg for the first 3–4 days before incremental increases by another 20 mcg are made to slowly titrate up to the desired dosage. The maximum clenbuterol dosage should be no more than 120–160 mcg per day (for males).