One think to remember is that this isn't a miracle pill. You have to take it for a while and be consistent with it. Don't buy a pot that lasts 15 days as you will not bother or forget to buy it again in time.
...my old GP used to say of these types of 'cures' that you might as well paint the back door green.
Look for a PL number and you'll know then if it's had UK standard clinical testing to verify its claims.