Who hasn’t wondered at one point how long different drugs stay in the body? There seems to be a general idea that stronger drugs remain in the body more than weaker ones, but that couldn’t really be farther from the truth. Heroin, for example, is generally undetectable in urine after three to five days, while marijuana, a much weaker drug can be detected up to 90 days after use. But let’s take it one step at a time.
The moment you smoke, snort or swallow a drug, your body starts to break it down; it metabolizes it. In the process, your body also produces metabolites or by-products of the drug. These by-products can be detected, which is why drug screens have become much more common, even for job interviews. However, drug tests have taken a lot of flack lately, and for good reasons. Business Insider went as far as calling them a “colossal scam” because some of the least dangerous drugs such as marijuana can be detected in your urine, blood, and hair for much longer than harder drugs such as heroin and meth.
The chart above is not even up to scale – cannabis can be detected almost a year after usage through blood tests. LSD for example vanishes after 3 days, while all traces of cocaine and methamphetamine last a month and a half at most. For urine tests, the situation is quite similar – cannabis stays detectable for much longer.
Hair tests are becoming more and more common, and I feel like this is a good thing – they seem to be less flawed than the alternatives, in that almost all drugs are detectable for up to 90 days, again with the exception of LSD, which seems determined to vanish from your body after three days.
Here’s the full list of how long drugs remain in your body:
Alcohol 3 – 5 days in urine, up to 90 days in hair and around 10 – 12 hours in your blood.
Amphetamines 1 – 3 days in urine, up to 90 days in hair and around 12 hours in your blood.
Barbiturates 2 – 4 days in urine, up to 90 days in hair and 1 – 2 days in your blood.
Benzodiazepines 3 to 6 weeks in urine, up to 90 days in hair and 2 – 3 days in your blood.
Cannabis 7 to 30 days in urine, up to 90 days in hair, two weeks in your blood.
Cocaine 3 – 4 days in urine, up to 90 days in hair, 1 – 2 days in your blood.
Codeine 1 day in urine, up to 90 days in hair, 12 hours in your blood.
Heroin 3 – 4 days in urine, up to 90 days in hair, up to 12 hours in your blood.
LSD – 1 – 3 days in urine, up to 3 days in hair, 2 – 3 hours in your blood.
MDMA (ecstasy) 3 – 4 days in urine, up to 90 days in hair and 1 – 2 days in your blood.
Methamphetamine (crystal meth) – 3 – 6 days in urine, up 90 days in hair, 24 – 72 hours in your blood.
Methadone – 3 – 4 days in urine, up to 90 days in hair, 24 – 36 hours in your blood.
Morphine 2 -3 days in urine, up to 90 days in hair, 6 – 8 hours in your blood.
Andrei's background is in geophysics, and he's been fascinated by it ever since he was a child. Feeling that there is a gap between scientists and the general audience, he started ZME Science -- and the results are what you see today.