There is a large number of product manufacturers who would claim they can prevent the condition, but we disagree. Pills like Propecia for example, a drug designed to block DHT (known as a DHT inbibitor), are usually taken in response to hair loss, therefore the condition has already occurred and much hair has already been lost. Furthermore, there is no guarantee that Propecia will prevent further hair loss, in fact in the majority of cases, it won’t. Products like Rogaine foam, Provillus and Procerin are the same. They are used as a responsive measure, not as a preventative, and most of the time they simply do not work.