Ketotifen is perhaps best known for its ability to inhibit the down regulation of beta receptors caused by drugs like clenbuterol and albuterol. Clenbuterol and its sister drug albuterol are typically cycled on and off because they desensitize the very receptors they act on to produce their fat mobilizing effect. Ketotifen used in conjunction with either would allow the use of these fat burning drugs for much longer periods. This is convenient if, for example, a person is wishes to do a T3 cycle for a month or six weeks and use albuterol to ehnance T3's fat burning. Adding ketotifen would allow that person to use the albuterol throughout the entire T3 cycle.