I would stick with just the Avodart if you are having no side effects. Adding another product that is said to be a 5-alpha-reductase inhibitor will just increase the risk of sides. Surely the Avodart should help control your loss on it's own.
Beta sitosterol belongs to a group of plant extracts called phytosterols and is thought to be a natural 5-alpha-reductase (5AR) inhibitor. This enzyme converts testosterone into dihydrotestosterone (DHT) and it is assumed that beta sitosterol helps prevent hair loss by blocking the formation of DHT, but no solid evidence supports this assumption.
This is the oldest story in the book and one used by many hair loss supplements. There are hundreds of compounds that are thought to block DHT and beta sitosterol, like so many other supplements, is not conclusively proven to do so.
