The anabolic properties of asthma drugs (clenbuterol,albuterol)

Clenbuterol has acquired a near-legendary status among some power athletes. Clenbuterol has a half-life of 27 hours, taking about five days to clear from the body. In contrast the longest-acting beta-2 agonist sold in the United States, salmeterol lasts only about 12 hours.
However, most researchers believe that the longer a drug takes to clear from the body, the higher the risk of side effects.
THE MYSTERY OF Clenbuterol:
It's uncertain how Clenbuterol and similar long-acting beta-2 agonists work to provide anabolic effects.
However, the beta-cell receptors that Clenbuterol interacts with are exquisitely sensitive and are known to "down-regulate" or close up if exposed to concentrated doses of beta-agonist drugs. Athletes often attempt to circumvent this biological limitation by using a "two-days-on, two-days-off" dosing schedule. Even so, the drug usually stops exerting thermogenic effects in as little as two weeks.


It is similar in structure to epinephrine, and like epinephrine, Clenbuterol can excessively stimulate the heart, resulting in a rapid heartbeat, or tachycardia. Other possible side effects include muscle tremors, heart-rhythm disturbances, headaches and muscle cramps. The latter problem is thought to occur because beta-2 agonist drugs affect potassium distribution in the body.

ARE ASTHMA INHALERS ANABOLIC?
Many athletes familiar with Clenbuterol might wonder if using commonly available metered-dose asthma-drug inhalers would produce similar responses. It's not unreasonable to assume that such drugs would offer some ergogenic benefits, since they fall into the same beta-2 agonist category as Clenbuterol.
The first thing to consider about asthma inhalers is their highly selective distribution. In essence, most of the drug is delivered to the lungs, with some slight spillover into the general blood circulation. Also, the dosage used in such sprays is usually in micrograms — not enough to promote any type of true ergogenic activity.

Any type of beta-2 agonist drug is capable of raising muscle strength by stimulating an influx of calcium into a portion of the muscle called the sarcoplasm. This in turn, leads to an increase in the binding of muscle contractile proteins (actin and myosin), resulting in more potent muscular contraction.
anabolic
The main problem with asthma drugs is the same as that typically occurring with Clenbuterol — cell-receptor downgrade. Some doctors fear that with continual usage, some asthma inhalers may not work at all thus endangering asthmatics who depend on them. Salmeterol, unlike albuterol, isn't for emergency use anyway; it takes 20-180 minutes to begin opening up the lungs, while albuterol works immediately.
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