Incredible How Long Is Weed Detectable In Hair References. Web in general, thc can be detected in saliva for up to 72 hours after use, though this window may be shorter for occasional users. When drugs enter your hair follicle, it enters below the scalp level.

Web a narcotics analysis on a hair sample can verify whether a person took drugs within the past year, depending on the length of the hair, and the drug testing on nails. Thc takes 3 months in the hair which is generally based on the time needed for root hairs to sprout past the scalp and. When drugs enter your hair follicle, it enters below the scalp level.