An agonist exhibit a positive biological effect similar to the receptor it stimulates. For instance, beta agonists (i.e. Salbutamol) stimulate the beta receptors in the bronchial system therefore leading to bronchodialtion. A competitive antagonist negates the function of the specific receptor by binding to the receptor binding site before the biological ligand. A non-competitive agonist negates the function of the specific receptor by binding to an allosteric site leading to a conformational change of the receptor site.
