Review Of How Long Does Hair Follicle Test Go Back Ideas. Web while urine drug testing can typically look back a week, hair follicle drug tests have a detection window of 90 days. Web the hair follicle drug test, when using the standard 1.5 inches of hair, can detect previous drug use up to 3 months.

It involves using light energy that targets pigment in the. Web get started what is a hair follicle drug test? Typically, a hair test goes back 90 days, but it depends on how fast your hair grows.