How Far Back Does A Mouth Swab Drug Test Test Back?

Up to 3 months ive learned .

Substance
Urine
Hair
Blood / Oral Fluid


Alcohol
6–24 hours ^[4]
up to 90 days
12–24 hours


Amphetamines (except meth)
1 to 3 days^[5]
up to 90 days
12 hours


Methamphetamine
3 to 5 days^[6]
up to 90 days
1–3 days^[6]


MDMA (Ecstasy)
24 hrs
up to 90 days
25 hours


Barbiturates (except phenobarbital)
1 day
up to 90 days
1 to 2 days


Phenobarbital
2 to 3 months^[7]
up to 90 days
4 to 7 days


Benzodiazepines
Therapeutic use: Up to 7 days. Chronic use (over one year): 4 to 6 weeks
up to 90 days
6 to 48 hours


Cannabis
3 to 5 days, and sometimes up to 30 days^[8]
up to 90 days ^[8]
Up to 24 hours ^[9]


Cocaine
2 to 5 days with exceptions for certain kidney disorders^[10]
up to 90 days
2 to 5 days^[11]


Codeine
2 to 3 days^[12]
up to 90 days
2 to 3 days^[12]


Cotinine (a break-down product of nicotine)
2 to 4 days
up to 90 days
2 to 4 days


Morphine
2 days
up to 90 days
1 – 2 days


Heroin
3 to 4 days^[13]
up to 90 days
1– 2 days


LSD
24 to 72 hours (however tests for LSD are very uncommon)
up to 3 days^{[citation needed]}
0 to 3 hours


Methadone
3 days
up to 97 days
24 hours


PCP
3 to 7 days for single use; up to 30 days in chronic users^[14]
up to 90 days
1 to 3 days^[14]