How Long Does Marijuana Stay in Your System?

Marijuana (THC) detection windows vary dramatically based on frequency of use and body fat.

Detection Windows by Test Type

• Urine: Single use: 3 days | Moderate: 5–7 days | Heavy: 10–15 days | Chronic heavy: 30+ days
• Blood: 1–2 days (occasional), up to 7 days (heavy)
• Saliva: 1–3 days
• Hair: up to 90 days

Factors Affecting Detection

• Body fat: THC is fat-soluble and stored in fat cells
• Frequency of use: chronic users accumulate THC
• Metabolism: faster metabolism clears faster
• Potency: higher THC content = longer detection

Why Marijuana Is Different

• THC-COOH (the metabolite tested) is stored in fat cells
• It releases slowly back into the bloodstream
• This makes marijuana detection much longer than other drugs