The Full Story
Clenbuterol is a bronchodilator medication. It can open up (dilate) air passages in lungs that become narrowed and full of mucus due to asthma or COPD (chronic obstructive pulmonary disease). Before you ask your doctor about clenbuterol or decide to "Google" it on your computer, you should know that it's not FDA-approved for humans in the United States; it is only available here for use in horses.
Clenbuterol Can Be Misused
Why should you keep on reading? Even without FDA approval, clenbuterol is still widely used by people in this country. It is best known for uses that are not medically approved and for side effects that are downright hazardous. People obtain it online under the nickname "Clen." Having some properties similar to anabolic steroids, clenbuterol is claimed to increase muscle mass. Because of this, bodybuilders and athletes sometimes take the oral or injectable forms. It might also reduce body fat, making it a popular weight loss supplement. Unfortunately, studies that support these claims of desirable effects on muscle and fat have only involved livestock and experimental animals such as mice and rats. Studies in humans have not shown similar benefits. Just the same, people still use it and clenbuterol has been listed by the World Anti-Doping Agency (WADA) and the International Olympic Committee (IOC) as a performance-enhancing drug that is banned in competitive sports.
The risks of misusing a drug like clenbuterol include its lack of proven effectiveness and its hazardous side effects. Clenbuterol is well-known to cause symptoms such as rapid heart rate (tachycardia), palpitations, tremors, anxiety, lowered blood potassium (hypokalemia), and elevated blood sugar (hyperglycemia). Adverse effects happen more often with the large doses used for performance enhancement and weight loss, which often run about 5-10 times higher than regular adult doses. Because the drug has a long half-life in the body, toxic symptoms can last from 1 to 8 days. In published reports, over 80% of people who developed toxic effects required care in a hospital. The medical literature contains numerous reports of patients with symptoms ranging from agitation and rapid heart rate all the way to seizures and cardiac arrest after swallowing abnormally large clenbuterol doses.
Other Hazards of Clenbuterol
Unlike anabolic steroids, clenbuterol is not a controlled substance. However, clenbuterol has been identified as an adulterant in street drugs such as heroin. After snorting or injecting heroin contaminated with clenbuterol, some patients have reported painful muscle spasms, agitation, and overactive reflexes. In 2005, the CDC reported 26 cases of clenbuterol poisoning among heroin users. They were hospitalized with symptoms such as rapid heart rate, palpitations, hypokalemia, chest pain, and agitation. Most were kept in the hospital for 5 days where they received intravenous fluids, potassium, and medications to slow down the heart. It is likely that many such cases go unreported because patients are afraid to seek medical care or health care providers might not recognize the symptoms of clenbuterol poisoning in illicit drug users.
Humans can also be poisoned by eating meat from animals given clenbuterol in their feed to promote weight gain and increase muscle mass. Both farmers and consumers of tainted meat have developed toxic symptoms associated with clenbuterol. Therefore, the United States and some European countries have made it illegal to add clenbuterol to animal feed.
Steps to Take in a Poisoning
Possible clenbuterol poisoning scenarios can involve substance abusers, bodybuilders, people trying to lose weight, people who were prescribed the drug in another country, and even small children who might unintentionally swallow some of an adult's supply. What should you do if you or someone you know could be experiencing toxicity from clenbuterol?
- First, try to determine how much clenbuterol was taken and why. If it's even slightly possible that someone took more than a usual single dose that would be given for asthma or COPD (about 40 mcg), the risk for troublesome effects is high and they should seek emergency help as soon as possible.
- At an emergency room, the person will be monitored for symptoms such as agitation, rapid heart rate, tremor, and abnormal blood potassium and glucose.
- Medications that might be used include intravenous fluids, sedatives for agitation, and beta-blocker drugs for tachycardia. If symptoms persist, hospitalization could be necessary for up to several days.
If you have questions about an adverse reaction or possible overdose of clenbuterol, immediately check the webPOISONCONTROL® online tool or call Poison Control at 1-800-222-1222 for help 24 hours a day, every day.
Leslie A. McCament-Mann, PhD, RPh
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