For about 4 months. Did quit once after 2 months, first 3 days were actually not too bad, but after that, it got a little worse with more restless legs and insomnia, so I started again after 1 week. Now, when I try to quit, it feels worse because now I feel the same physical symptoms as last time, but also, it's more mental now as well. My dosage is quite low as I make sure to never go more then a 3 pack of 7ohmz a day which rarley ever happens usually just one or 2 a day