Weed (marijuana) can stay in your system for varying lengths of time depending on the type of drug test, frequency of use, metabolism, and other individual factors.
Detection Times by Test Type:
- Blood: THC is detectable for about 12 to 48 hours after use for most people, but in heavy users, it can be detected up to a week
- Saliva: Detectable for 24 to 72 hours after use
- Urine: The most common test, can detect THC metabolites from about 3 days after a single use up to 30 days or more for heavy, chronic users. Moderate use may be detected for 5-15 days, and daily heavy use for 30 days or longer
- Hair: Can detect marijuana use for up to 90 days or longer, as THC metabolites accumulate in hair follicles
Factors Affecting Detection Time:
- Frequency and amount of use (more frequent/heavy use leads to longer detection times)
- Method of consumption (smoking vs. edibles)
- Individual metabolism, body fat, hydration, health, and genetics
- Type of drug test used
Summary:
- Single use: THC detectable in urine for up to 3 days, blood and saliva up to 1-2 days
- Moderate use (few times per week): urine detection up to 5-7 days
- Daily/heavy use: urine detection up to 30 days or more
- Hair tests can detect use for up to 90 days regardless of frequency
Thus, while the psychoactive effects of weed typically last a few hours, THC and its metabolites can remain in your body and be detected by drug tests for days to months after use depending on these factors.
