How long does drugs stay in your hair?

Short answer: Approximately 90 days.

With hair follicle testing, you can detect some major drugs like marijuana, methamphetamine, opiates, ecstasy and cocaine and marijuana. Or sometimes it is used as a confirmatory testing after getting positive result in urine testing. Procedure of hair follicle testing is very simple. You just need to submit 1.5 inch hair strands. Usually, hair grows at the rate of 0.5 inch/ day. That means 1.5 inch long hair strand depicts drug history of last three months. You might think that to beat the drug test with hair screening is quite difficult. Yes, because in hair drug testing you need to submit minimum 70-80 hair strands each with 1.5 inch long. If you fail to submit hair strands from the scalp, then hair from other body parts are also quite acceptable.