Clenbuterol, medically used throughout many parts of the world as a broncodilator for the treatment of asthma, is a recent and popular addition to the realm of athletics. Clenbuterol is a beta-2 agonist, with properties somewhat similar to adrenaline. It acts as a CNS stimulant and users quite commonly report side effects such as shaky hands, insomnia, sweating, increased blood pressure and nausea. These side effects generally subside quickly once the user becomes accustomed to the drug. Athletes find
clenbuterol attractive for it's pronounced thermogenic effects as well as mild anabolic properties (slight strength increase).  Clenbuterol generally come is 20mcg tablets, although it is also available in syrup and injectable form. Users will tailor their dosage individually, depending on desired results and side effects, but somewhere in the range of 2-8 tablets per day is most common. For fat loss, clenbuterol seems to stay effective for 3-6 weeks. During this period, users will notice a slightly elevated body temperature. This makes clen a very attractive, and today almost mandatory, pre-contest drug. Soon though, the effects do subside and the body temperature drops back to normal. At this point increasing the dosage would not be very effective and a break should be taken. When looking for strength gains, clen seems to be effective for a shorter period, around 3 weeks.  Currently, counterfeits of clenbuterol do exist, but they are scarce and most are bottles with loose tablets. Clenbuterol should only be trusted when purchased in foil and plastic strips, preferably with accompanying box and paperwork.