I just got my results back from a home test kit; I had 55ng level for weed. I am 48 yrs and weigh 185lbs. I tested myself after 20 days of non-use. Prior to that, I smoked for 2 months, everyday. Prior to that, I did not smoke for 2 months. I did not drink lots of water. I did not exercise. I took 4 goldenseal root capsules everyday for 3 days prior, and waited one day before testing myself. I use the first sample of the day. These are my results I hope this might help others.