Clenbuterol

Clenbuterol (trade names: Spiropent, Ventipulmin) 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.

Effects and dosage
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 causes an increase in aerobic capacity, central nervous system stimulation, and an increase in blood pressure and oxygen transportation. It increases the rate at which body fat is metabolized, simultaneously increasing the body's BMR. It is commonly used for smooth muscle relaxant properties. This means that it is a bronchodilator and tocolytic.

Clenbuterol is usually used in dosages anywhere from 20-60 micrograms (mcg) a day when prescribed. A dose of about 120 mcg (women) or 140 mcg (men) should never be exceeded in a day.

Clenbuterol is also prescribed for treatment of horses; however, equestrian usage is usually the liquid form of clenbuterol.

Human use
Clenbuterol is approved for use in some countries (via prescription only) as a bronchodilator for asthma patients. Recently though, the drug has been publicized for its off-label use as a weight loss drug, similar to usage of other sympathomimetic amines such as ephedrine. It is commonly used as a slimming aid despite lack of sufficient clinical testing either supporting or negating such use.

Legal status
Clenbuterol is not an ingredient of any therapeutic drug approved by the U.S. Food and Drug Administration and is now banned for IOC-tested athletes. Clenbuterol is legal in the US for use on animals, but possession is illegal otherwise. See further at List of doping cases in sport. Clenbuterol is illegal for use in food producing animals. Administration of Clenbuterol to any animal that could be used as food for human consumption is strictly banned by the FDA. See www.farad.org for a complete list of prohibited drugs. (http://www.farad.org/eldu/prohibit.asp)

Use as performance-enhancing drug
As a Beta 2 sympathomimetic, Clenbuterol has also been used as a performance-enhancing drug,. In 2010, three cyclists were also accused of taking the drug. Three-time Tour de France champion Alberto Contador of Spain tested positive for the drug at the 2010 Tour de France. The news came out during the UCI Road Cycling World Championships held in Geelong, Australia. In May, the UCI suspended Italian cyclist Alessandro Colo, and Chinese rider Li Fuyu, a member of Team RadioShack, was suspended after testing positive for the drug during a Belgian race. A number of athletes were also banned after using the drug, including British hurdler Callum Priestley, Chinese Olympic judo champion Tong Wen and Polish canoeist Adam Seroczynski.

American swimmer Jessica Hardy tested positive at the U.S. trials in July 2008. She served a one-year suspension, having claimed she unknowingly took the drug in a contaminated food supplement. Former New York Mets clubhouse employee Kirk Radomski admitted to distributing clenbuterol to dozens of current and former Major League Baseball players and associates in his plea deal.

Polish sprint canoer Adam Seroczyński was disqualified for taking this drug after he finished fourth in the K-2 1000 m event at the 2008 Summer Olympics in Beijing, and Chinese cyclist Li Fuyu tested positive for it at the Dwars door Vlaanderen race in Belgium on March 24, 2010.

In the 2010 Tour de France, Alberto Contador tested positive for clenbuterol. He claims it was due to food contamination, citing the 50 picogram (5 × 10−11 g) per millilitre concentration of the drug in his sample. He was handed a one-year suspension from competition by the Spanish Cycling Federation (RFEC). On February 14, 2011, Contador was cleared of doping by the Spanish cycling federation, which canceled its January 26 proposal for a one-year ban. Traces of the amine from meat in the diet is regularly turning up in athletes' blood.

In September 2010, St. Louis Cardinals minor league shortstop Lainer Bueno received a 50-game suspension for the 2011 season as a result of testing positive for clenbuterol.

Contraindications and cautions

 * Hypersensitivity to the medicine
 * Thyrotoxicosis
 * Tachycardia
 * Subaortic stenosis
 * Acute myocardial infarction
 * Hypertension
 * Pregnancy

Overdosage
Excessive usage over the recommended dose of about 120 μg can cause muscle tremor, headache, dizziness and gastric irritation. Persons self-administering the drug for weight loss or to improve athletic performance have experienced nausea, vomiting, diaphoresis, palpitations, tachycardia and myocardial infarction. Use of the drug may be confirmed by detecting its presence in semen or urine.

Food contamination
In September 2006 over 330 people in Shanghai were reported to have been poisoned by eating pork contaminated by clenbuterol that had been fed to the animals to keep their meat lean.

In February 2009, at least 70 people in one Chinese province (Guangdong) suffered food poisoning after eating pig organs believed to contain clenbuterol residue. The victims complained of stomach aches and diarrhea after eating pig organs bought in local markets.

In March 2011, China's Ministry of Agriculture (MOA) said that the government would launch a one-year crackdown on illegal additives in pig feed, after a subsidiary of Shuanghui Group, China's largest meat producer, was exposed for using clenbuterol-contaminated pork in its meat products. A total of 72 people in central Henan Province, where Shuanghui is based, were taken into police custody for allegedly producing, selling or using clenbuterol.

Veterinary use
The European Union prohibits the use of clenbuterol in food-producing animals. It is, however, used in other parts of the world for the treatment of allergic respiratory disease in horses, as it is a bronchodilator. A common trade name is Ventipulmin. It can be used both orally and intravenously. It is also used in cattle to relax the uterus in cows, usually at the time of parturition. It is also a nonsteroidal anabolic and metabolism accelerator, through a mechanism not well understood. Its ability to increase the muscle-to-fat body ratio makes its illegal use in livestock popular to obtain leaner meats.