I have taken low doses of Biotin for about 20 years; about 1,000/2,000 without any problems and great results. After taking Wellbutrin for abouta year, I noticed gradual hair loss. I stopped taking it and felt desperate to regain my thick hair. I choose to buy Biotin 10,000 to speed up the process; big mistake!!! Within a few months, my scalp became itchy. I sought treatment and help, but no doctor could determined be the cause. I was told to use dandruff shampoo, which never helped. A few months later, I began having itchy patches on my body; mainly my elbows, knees, low back, outter thighs and my stomach. Again, I asked a few doctors for help and was told that I have Ecezma for the first time in my life. I used the steroid cream without much relief, so began feeling hopeless and depressed. The itching is so bad that I rarely get a good nights sleep. Long story short, I threw out all of my vitamins, thinking it had to be an allergic reaction to one of them. The only one I kept was the biotin 10,000. As my itching didn’t subside, I finally realized that it must be the biotin. I did some on-line research and found that doses over 2,500 can cause skin eruptions, itchy rash and scalp!!!! I have stopped taking it, and the it hi g is slowly becoming less severe. I am truly hoping that gmo has only get better, as I have been determined to find the cause if my itching. I have never had this issue before, and pray that I have found the reason. So far, so good!!! I can see that they don’t even list a Biotin 10,000 below, so picked Natures Bounty 5,000, so x2 a day!!!?? ugh!!! I am just hoping that I can spare someone the anguish that I have endured. More is definitely not better, and just because Amazon sells it doesn’t mean it’s safe.Read More Read Less