t is most often prepared in 2Omcg tablets, but Clenbuterol is also available in syrup and injectable form. This drug belongs to a broad group of drugs knows as sympathomimetics. Clenbuterol affect that sympathetic nervous system in a wide number of ways, largely mediated by the distribution of adrenoceptors.
Use of Clenbuterol

The drug is specifically a selective beta-2 sympathomimetic, primarily affecting only one of the three subsets of beta-receptors. Of particular interest is the fact that Clenbuterol has little beta-i stimulating activity. Since beta-i receptors are closely tied to the cardiac effects of adrenoceptors, this allows to reduce reversible airway obstruction (and effect of beta-2 stimulation) with much less cardiovascular side effects compared to non-selective beta agonists. Clinical studies with Clenbuterol show it is extremely effective as a bronchodilator, with a low level of user complaints and high patient compliance Clenbuterol also exhibits an extremely long half-life in the body, which is measured to be approximately 34 hours long. This makes steady blood levels easy to achieve, requiring only a single or twice daily dosing schedule at most. This of course makes it much easier for the patient to use, and may tie into its high compliance rate.