Mast Cell Stabilizers
Cromolyn Salts, Cromolyn Sodium, Nedocromil Sodium
One way to stop histamine from being released would be to stop from degranulating - even if was crosslinked. Several drugs have this property. Cromolyn was the first drug licensed as a mast cell stabilizer, that is, inhibit degranulation and activation. It is available for use in the nose, lungs and GI tract. Its major limitation is a short duration of action (approx. 6 hours) and lack of available systemic preparation. Recently, a related compound called Nedocromil has been released in the U.S for use in asthmatics. It appears to have a longer action duration and may have more
properties than Cromolyn.
Since the process of mast cell activation, mediator production and chemotaxis takes longer than mast cell degranulation, allergic reactions often have two distinct phases - the first or early phase occurs in minutes. The second or late phase occurs some 3-12 hours later and is an reaction due to mast cell and eosinophil products. have no effect on late phase reactions while have little direct effect on early phase reactions. Cromolyn and nedocromil appear to be effective against both reaction phases.