The instructions that came with my first bottle stated 20 - 25 drops twice a day as the therapeutic dosage, whatever they mean with that. I wasn't going to waste any more time. I am sick of being sick. So far it's working great. I will go down in drops when those electrical feeling buzzes in my head go away....and they are almost gone. I am thrilled! I don't know if I would have been at this point with only 15 drops or 20 drops or whatever. I decided to go for the kill....lol.....and I am glad I did!