I never use cocaine and have passed hair follicle tests before. However 45 days ago I took 3 small bumps of cocaine while drinking with old friends. I cut my hair approximately 2 1/2 weeks after that. I have done the macuju method 3 times and also have been using selsum blue shampoo. I am wondering if anyone has any experience with this and if I need to be more worried that it will test positive even with the small amount I tried and since I never have used prior. I may have another hair follicle test coming up in the next couple of weeks for work and do not want to fail. Any help or ideas? My hair is always relatively short and it is currently 1 inch long on top.

Cocaine stays in hair for about 90 days. The hair on your head is not the only hair that can be used to test. People come into testing labs with shaved heads all the time.

The best way to pass is not to use - I'm surprised you used 3 bumps your very first time.

Any any rate, it's INSIDE the hair, not OUTSIDE - so shampoo does not matter.